@article {4941, title = {Biogeographic survey of soil bacterial communities across Antarctica}, journal = {Microbiome}, volume = {12}, year = {2024}, month = {01/2024}, abstract = {

Antarctica and its unique biodiversity are increasingly at risk from the effects of global climate change and other human influences. A significant recent element underpinning strategies for Antarctic conservation has been the development of a system of Antarctic Conservation Biogeographic Regions (ACBRs). The datasets supporting this classification are, however, dominated by eukaryotic taxa, with contributions from the bacterial domain restricted to Actinomycetota and Cyanobacteriota. Nevertheless, the ice-free areas of the Antarctic continent and the sub-Antarctic islands are dominated in terms of diversity by bacteria. Our study aims to generate a comprehensive phylogenetic dataset of Antarctic bacteria with wide geographical coverage on the continent and sub-Antarctic islands, to investigate whether bacterial diversity and distribution is reflected in the current ACBRs.

}, keywords = {LTER-MCM, Antarctic Conservation Biogeographic Regions (ACBRs), Antarctic soil microbiome, bioclimatic variables, biogeography, microbial diversity, regionalization, soils}, doi = {10.1186/s40168-023-01719-3}, url = {https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-023-01719-3}, author = {Varliero, Gilda and Lebre, Pedro H. and Byron Adams and Steven L. Chown and Peter Convey and Dennis, Paul G. and Fan, Dandan and Ferrari, Belinda and Frey, Beat and Hogg, Ian D. and Hopkins, David W. and Kong, Weidong and Makhalanyane, Thulani and Matcher, Gwynneth and Newsham, Kevin K. and Stevens, Mark I. and Weigh, Katherine V. and Cowan, Don A.} } @article {4844, title = {Causes and characteristics of electrical resistivity variability in shallow (<4 m) soils in Taylor Valley, East Antarctica}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {128}, year = {2023}, month = {02/2023}, pages = {e2022JF006696}, abstract = {

Airborne electromagnetic surveys collected in December 2011 and November 2018 and three soil sampling transects were used to analyze the spatial heterogeneity of shallow (\<4 m) soil properties in lower Taylor Valley (TV), East Antarctica. Soil resistivities from 2011 to 2018 ranged from \∼33 Ωm to \∼3,500 Ωm with 200 Ωm assigned as an upper boundary for brine-saturated sediments. Elevations below \∼50 m above sea level (masl) typically exhibit the lowest resistivities with resistivity increasing at high elevations on steeper slopes. Soil water content was empirically estimated from electrical resistivities using Archie\&$\#$39;s Law and range from \∼\<1\% to \∼68\% by volume. An increase in silt- and clay-sized particles at low elevations increases soil porosity but decreases hydraulic conductivity, promoting greater residence times of soil water at low elevations near Lake Fryxell. Soil resistivity variability between 2011 and 2018 shows soils at different stages of soil freeze-thaw cycles, which are caused predominantly by solar warming of soils as opposed to air temperature. This study furthers the understanding of the hydrogeologic structure of the shallow subsurface in TV and identifies locations of soils that are potentially prone to greater rates of thaw and resulting ecosystem homogenization of soil properties from projected increases in hydrological connectivity across the region over the coming decades.

}, keywords = {LTER-MCM, active layer, airborne electromagnetic surveys, McMurdo Dry Valleys, permafrost dynamics}, issn = {2169-9003}, doi = {10.1029/2022JF006696}, url = {https://onlinelibrary.wiley.com/doi/10.1029/2022JF006696}, author = {Gutterman, William S. and Peter T. Doran and Ross A. Virginia and John E. Barrett and Myers, Krista F. and Tulaczyk, Slawek M. and Foley, Neil T. and Jill A. Mikucki and Hilary A. Dugan and Grombacher, Denys and Bording, Thue S. and Auken, E.} } @article {4942, title = {The distribution of surface soil moisture over space and time in eastern Taylor Valley, Antarctica}, journal = {Remote Sensing}, volume = {15}, year = {2023}, month = {06/2023}, pages = {3170}, abstract = {

Available soil moisture is thought to be the limiting factor for most ecosystem processes in the cold polar desert of the McMurdo Dry Valleys (MDVs) of Antarctica. Previous studies have shown that microfauna throughout the MDVs are capable of biological activity when sufficient soil moisture is available (~2\–10\% gravimetric water content), but few studies have attempted to quantify the distribution, abundance, and frequency of soil moisture on scales beyond that of traditional field work or local field investigations. In this study, we present our work to quantify the soil moisture content of soils throughout the Fryxell basin using multispectral satellite remote sensing techniques. Our efforts demonstrate that ecologically relevant abundances of liquid water are common across the landscape throughout the austral summer. On average, the Fryxell basin of Taylor Valley is modeled as containing 1.5 \± 0.5\% gravimetric water content (GWC) across its non-fluvial landscape with ~23\% of the landscape experiencing an average GWC \> 2\% throughout the study period, which is the observed limit of soil nematode activity. These results indicate that liquid water in the soils of the MDVs may be more abundant than previously thought, and that the distribution and availability of liquid water is dependent on both soil properties and the distribution of water sources. These results can also help to identify ecological hotspots in the harsh polar Antarctic environment and serve as a baseline for detecting future changes in the soil hydrological regime.

}, keywords = {LTER-MCM, Dry valleys, ecology, hydrology, remote sensing, soil moisture}, doi = {10.3390/rs15123170}, url = {https://www.mdpi.com/2072-4292/15/12/3170}, author = {Salvatore, Mark R. and Barrett, John E. and Fackrell, Laura E. and Sokol, Eric R. and Levy, Joseph S. and Kuentz, Lily C. and Gooseff, Michael N. and Adams, Byron J. and Power, Sarah N. and Knightly, J. Paul and Matul, Haley M. and Szutu, Brian and Doran, Peter T.} } @phdthesis {4862, title = {Microbial life in challenging environments}, volume = {Ph.D.}, year = {2023}, school = {University of Colorado Boulder}, type = {doctoral}, address = {Boulder, CO}, abstract = {

Microorganisms are nearly ubiquitous on Earth, but the identity and function of microbial communities are inherently dependent on the properties of the specific environment in question. Here, I have studied soils around the world to answer questions about how the functional attributes of microorganisms allow them to respond to challenging environmental conditions. First, I explore how microbial communities in soils change across environmental gradients in Antarctica. I show that microbes in Antarctic surface soils are most restricted by low temperatures, low water availability, and high concentrations of salt. Microbial communities near the polar plateau, the most challenging environment, are dominated by Actinobacteria and Chloroflexi, and are enriched in genes associated with the oxidation of hydrogen gas as an energy source. Second, I show that the earliest microbial colonizers of a newly-formed volcanic island in the Kingdom of Tonga are chemolithotrophs that appear to have come from nearby geothermal systems. While many of these microbes utilize sulfur as an energy source, the most abundant organisms have genes that indicate they can oxidize trace gases including carbon monoxide and hydrogen. Finally, I show that organisms associated with carbon limited subsurface soils tend to have smaller genomes, grow more slowly, and have more gene pathways associated with metabolism and the storage of carbon. Taken together, these studies shed light on microbial survival in challenging soil environments and show the varied ways in which microbial communities interact with and are affected by their surroundings.

}, keywords = {LTER-MCM, Antarctica, environmental conditions, microbial ecology, microorganisms, soils, tonga}, url = {https://www.proquest.com/docview/2814734209}, author = {Dragone, Nicholas B.}, editor = {Noah Fierer} } @article {4943, title = {Strong dispersal limitation of microbial communities at Shackleton Glacier, Antarctica}, journal = {mSystems}, volume = {8}, year = {2023}, month = {01/2023}, abstract = {

Microbial communities can be structured by both deterministic and stochastic processes, but the relative importance of these processes remains unknown. The ambiguity partly arises from an inability to disentangle soil microbial processes from confounding factors, such as aboveground plant communities or anthropogenic disturbance. In this study, we characterized the relative contributions of determinism and stochasticity to assembly processes of soil bacterial communities across a large environmental gradient of undisturbed Antarctic soils. We hypothesized that harsh soils would impose a strong environmental selection on microbial communities, whereas communities in benign soils would be structured largely by dispersal. Contrary to our expectations, dispersal was the dominant assembly mechanism across the entire soil environmental gradient, including benign environments. The microbial community composition reflects slowly changing soil conditions and dispersal limitation of isolated sites. Thus, stochastic processes, as opposed to deterministic, are primary drivers of soil ecosystem assembly across space at our study site. This is especially surprising given the strong environmental constraints on soil microorganisms in one of the harshest environments on the planet, suggesting that dispersal could be a driving force in microbial community assembly in soils worldwide.

}, keywords = {LTER-MCM, community assembly, determinism, dispersal, niche, stochasticity}, doi = {10.1128/msystems.01254-22}, url = {https://journals.asm.org/doi/full/10.1128/msystems.01254-22}, author = {Lemoine, Nathan P. and Byron Adams and Melisa A. Diaz and Dragone, Nicholas B. and Franco, Andr{\'e} L. C. and Noah Fierer and W. Berry Lyons and Hogg, Ian D. and Diana H. Wall}, editor = {Lurgi, Miguel} } @article {4718, title = {Elevational constraints on the composition and genomic attributes of microbial communities in Antarctic soils}, journal = {mSystems}, volume = {7}, year = {2022}, month = {01/2022}, pages = {e01330-21}, abstract = {

The inland soils found on the Antarctic continent represent one of the more challenging environments for microbial life on Earth. Nevertheless, Antarctic soils harbor unique bacterial and archaeal (prokaryotic) communities able to cope with extremely cold and dry conditions. These communities are not homogeneous, and the taxonomic composition and functional capabilities (genomic attributes) of these communities across environmental gradients remain largely undetermined. We analyzed the prokaryotic communities in soil samples collected from across the Shackleton Glacier region of Antarctica by coupling quantitative PCR, marker gene amplicon sequencing, and shotgun metagenomic sequencing. We found that elevation was the dominant factor explaining differences in the structures of the soil prokaryotic communities, with the drier and saltier soils found at higher elevations harboring less diverse communities and unique assemblages of cooccurring taxa. The higher-elevation soil communities also had lower maximum potential growth rates (as inferred from metagenome-based estimates of codon usage bias) and an overrepresentation of genes associated with trace gas metabolism. Together, these results highlight the utility of assessing community shifts across pronounced environmental gradients to improve our understanding of the microbial diversity found in Antarctic soils and the strategies used by soil microbes to persist at the limits of habitability.

}, keywords = {LTER-MCM, Antarctica, microbial ecology, soil microbiology, soils}, doi = {10.1128/msystems.01330-21}, url = {https://journals.asm.org/doi/full/10.1128/msystems.01330-21}, author = {Dragone, Nicholas B. and Henley, Jessica B. and Holland-Moritz, Hannah and Melisa A. Diaz and Hogg, Ian D. and W. Berry Lyons and Diana H. Wall and Byron Adams and Noah Fierer}, editor = {Mackelprang, Rachel} } @article {4759, title = {Limits to the three domains of life: Lessons from community assembly along an Antarctic salinity gradient}, journal = {Extremophiles}, volume = {26}, year = {2022}, month = {04/2022}, pages = {15}, abstract = {

Extremophiles exist among all three domains of life; however, physiological mechanisms for surviving harsh environmental conditions differ among Bacteria, Archaea and Eukarya. Consequently, we expect that domain-specific variation of diversity and community assembly patterns exist along environmental gradients in extreme environments. We investigated inter-domain community compositional differences along a high-elevation salinity gradient in the McMurdo Dry Valleys, Antarctica. Conductivity for 24 soil samples collected along the gradient ranged widely from 50 to 8355 \µS cm-1. Taxonomic richness varied among domains, with a total of 359 bacterial, 2 archaeal, 56 fungal, and 69 non-fungal eukaryotic operational taxonomic units (OTUs). Richness for bacteria, archaea, fungi, and non-fungal eukaryotes declined with increasing conductivity (all P\ \<\ 0.05). Principal coordinate ordination analysis (PCoA) revealed significant (ANOSIM R\ =\ 0.97) groupings of low/high salinity bacterial OTUs, while OTUs from other domains were not significantly clustered. Bacterial beta diversity was unimodally distributed along the gradient and had a nested structure driven by species losses, whereas in fungi and non-fungal eukaryotes beta diversity declined monotonically without strong evidence of nestedness. Thus, while increased salinity acts as a stressor in all domains, the mechanisms driving community assembly along the gradient differ substantially between the domains.

}, keywords = {LTER-MCM, Antarctica, inter-domain response, McMurdo Dry Valleys, salinity, species richness patterns}, doi = {10.1007/s00792-022-01262-3}, url = {https://link.springer.com/article/10.1007/s00792-022-01262-3}, author = {Jiang, Xiaoben and David J. Van Horn and Okie, Jordan G. and Heather N. Buelow and Schwartz, Egbert and Colman, Daniel R. and Feeser, Kelli L. and Cristina D. Takacs-Vesbach} } @article {4777, title = {Long-term stream hydrology and meteorology of a polar desert, the McMurdo Dry Valleys, Antarctica}, journal = {Hydrological Processes}, volume = {36}, year = {2022}, month = {06/2022}, pages = {e14623}, abstract = {

The McMurdo Dry Valleys (MDVs; 77.50\°S, 162.25\°E) make up the largest ice-free region of Antarctica at 3500 km2. Their position near the coast of the Ross Sea provides for a milder climate than much of the rest of the continent. Alpine and piedmont glaciers in the MDVs melt during the austral summer providing water to down gradient streams and terminal lakes on valley floors. There are currently 14 meteorological stations and 17 stream gauges operating across the MDVs, some with continuous records that go back to 1969. This relatively high density of monitoring stations reflects the fact that glaciers of different sizes and elevation ranges are the main source of water to streams. Thus, each glacier represents a different watershed. The bulk of these records start in the late 1980s/early 1990s. These data collection activities directly support research endeavors of the McMurdo Dry Valleys Long Term Ecological Research project, as well as a host of other science groups working in the MDVs. As such, both real time data and archived data from these sites is available through the online database interface of the project (https://mcmlter.org).

}, keywords = {LTER-MCM, Antarctica, LTER, McMurdo Dry Valleys, meltwater streams, polar desert, research catchment}, issn = {0885-6087}, doi = {10.1002/hyp.14623}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/hyp.14623}, author = {Gooseff, Michael N. and McKnight, Diane M. and Doran, Peter T. and Fountain, Andrew} } @article {4758, title = {Patterns of interdisciplinary collaboration resemble biogeochemical relationships in the McMurdo Dry Valleys, Antarctica: A historical social network analysis of science, 1907{\textendash}2016}, journal = {Polar Research}, volume = {41}, year = {2022}, month = {04/2022}, pages = {8037}, abstract = {

Co-authorship networks can provide key insights into the production of scientific knowledge. This is particularly interesting in Antarctica, where most human activity relates to scientific research. Bibliometric studies of Antarctic science have provided a useful understanding of international and interdisciplinary collaboration, yet most research has focused on broad-scale analyses over recent time periods. Here, we take advantage of a \‘Goldilocks\’ opportunity in the McMurdo Dry Valleys, an internationally important region of Antarctica and the largest ice-free region on the continent. The McMurdo Dry Valleys have attracted continuous and diverse scientific activity since 1958. It is a geographically confined region with limited access, making it possible to evaluate the influence of specific events and individuals. We trace the history of environmental science in this region using bibliometrics and social network analysis. Our results show a marked shift in focus from the geosciences to the biosciences, which mirrors wider trends in the history of science. Collaboration among individuals and academic disciplines increased through time, and the most productive scientists in the network are also the most interdisciplinary. Patterns of collaboration among disciplines resemble the biogeochemical relationships among respective landscape features, raising interesting questions about the role of the material environment in the development of scientific networks in the region, and the dynamic interaction with socio-cultural and political factors. Our focused, historical approach adds nuance to broad-scale bibliometric studies and could be applied to understanding the dynamics of scientific research in other regions of Antarctica and elsewhere.

}, keywords = {LTER-MCM, critical physical geography, environmental history, history of science, science and technology studies, scientometrics, visual network analysis}, doi = {10.33265/polar.v41.8037}, url = {https://polarresearch.net/index.php/polar/article/view/8037}, author = {Chignell, Stephen M. and Howkins, Adrian and Gullett, Poppie and Andrew G Fountain} } @article {4689, title = {Response of Antarctic soil fauna to climate-driven changes since the Last Glacial Maximum}, journal = {Global Change Biology}, volume = {28}, year = {2022}, month = {01/2022}, abstract = {

Understanding how terrestrial biotic communities have responded to glacial recession since the Last Glacial Maximum (LGM) can inform present and future responses of biota to climate change. In Antarctica, the Transantarctic Mountains (TAM) have experienced massive environmental changes associated with glacial retreat since the LGM, yet we have few clues as to how its soil invertebrate-dominated animal communities have responded. Here, we surveyed soil invertebrate fauna from above and below proposed LGM elevations along transects located at 12 features across the Shackleton Glacier region. Our transects captured gradients of surface ages possibly up to 4.5 million years and the soils have been free from human disturbance for their entire history. Our data support the hypothesis that soils exposed during the LGM are now less suitable habitats for invertebrates than those that have been exposed by deglaciation following the LGM. Our results show that faunal abundance, community composition, and diversity were all strongly affected by climate-driven changes since the LGM. Soils more recently exposed by glacial recession (as indicated by distances from present ice surfaces) had higher faunal abundances and species richness than older exposed soils. Higher abundances of the dominant nematode Scottnema were found in older exposed soils, while Eudorylaimus, Plectus, tardigrades, and rotifers preferentially occurred in more recently exposed soils. Approximately 30\% of the soils from which invertebrates could be extracted had only Scottnema, and these single-taxon communities occurred more frequently in soils exposed for longer periods of time. Our structural equation modeling of abiotic drivers highlighted soil salinity as a key mediator of Scottnema responses to soil exposure age. These changes in soil habitat suitability and biotic communities since the LGM indicate that Antarctic terrestrial biodiversity throughout the TAM will be highly altered by climate warming.

}, keywords = {LTER-MCM, biodiversity, climate change, glacial retreat, nematodes, Shackleton Glacier, soil invertebrates}, issn = {1354-1013}, doi = {10.1111/gcb.15940}, url = {https://onlinelibrary.wiley.com/doi/10.1111/gcb.15940}, author = {Franco, Andr{\'e} L. C. and Byron Adams and Melisa A. Diaz and Lemoine, Nathan P. and Dragone, Nicholas B. and Noah Fierer and W. Berry Lyons and Hogg, Ian D. and Diana H. Wall} } @article {4838, title = {The time is right for an Antarctic biorepository network}, journal = {Proceedings of the National Academy of Sciences}, volume = {119}, year = {2022}, month = {12/2022}, abstract = {

Antarctica is a central driver of the Earth\’s climate and health. The Southern Ocean surrounding Antarctica serves as a major sink for anthropogenic CO2 and heat, and the loss of Antarctic ice sheets contributes significantly to sea level rise and will continue to do so as the loss of ice sheets accelerates, with sufficient water stores to raise sea levels by 58 m. Antarctica\&$\#$39;s marine environment is home to a number of iconic species, and the terrestrial realm harbors a remarkable oasis for life, much of which has yet to be discovered. Distinctive oceanographic features of the Southern Ocean\—including the Antarctic Circumpolar Current, the Antarctic Polar Front, and exceptional depths surrounding the continent\—coupled with chronically cold temperatures have fostered the evolution of a vast number of uniquely coldadapted species, many of which are found nowhere else on the Earth. The Antarctic marine biota, for example, displays the highest level of species endemism on the Earth. However, warming, ocean acidification, pollution, and commercial exploitation threaten the integrity of Antarctic ecosystems. Understanding changes in the biota and its capacities for adaptation is imperative for establishing effective policies for mitigating the impacts of climate change and sustaining the Antarctic ecosystems that are vital to global health.

}, keywords = {LTER-MCM}, issn = {0027-8424}, doi = {10.1073/pnas.2212800119}, url = {https://www.pnas.org/doi/10.1073/pnas.2212800119}, author = {O{\textquoteright}Brien, Kristin M. and Crockett, Elizabeth L. and Byron Adams and Amsler, Charles D. and Appiah-Madson, Hannah J. and Collins, Allen and Desvignes, Thomas and Detrich, H. William and Distel, Daniel L. and Eppley, Sarah M. and Frable, Benjamin W. and Franz, Nico M. and Grim, Jeffrey M. and Kocot, Kevin M. and Mahon, Andrew R. and Mayfield-Meyer, Teresa J. and Jill A. Mikucki and Moser, William E. and Schmull, Michaela and Seid, Charlotte A. and Smith, Craig R. and Todgham, Anne E. and Watkins-Colwell, Gregory J.} } @article {4585, title = {Antarctic water tracks: Microbial community responses to variation in soil moisture, pH, and salinity}, journal = {Frontiers in Microbiology}, volume = {12}, year = {2021}, month = {01/2021}, abstract = {

Ice-free soils in the McMurdo Dry Valleys select for taxa able to cope with challenging environmental conditions, including extreme chemical water activity gradients, freeze-thaw cycling, desiccation, and solar radiation regimes. The low biotic complexity of Dry Valley soils makes them well suited to investigate environmental and spatial influences on bacterial community structure. Water tracks are annually wetted habitats in the cold-arid soils of Antarctica that form briefly each summer with moisture sourced from snow melt, ground ice thaw, and atmospheric deposition via deliquescence and vapor flow into brines. Compared to neighboring arid soils, water tracks are highly saline and relatively moist habitats. They represent a considerable area (\∼5\–10 km2) of the Dry Valley terrestrial ecosystem, an area that is expected to increase with ongoing climate change. The goal of this study was to determine how variation in the environmental conditions of water tracks influences the composition and diversity of microbial communities. We found significant differences in microbial community composition between on- and off-water track samples, and across two distinct locations. Of the tested environmental variables, soil salinity was the best predictor of community composition, with members of the Bacteroidetes phylum being relatively more abundant at higher salinities and the Actinobacteria phylum showing the opposite pattern. There was also a significant, inverse relationship between salinity and bacterial diversity. Our results suggest water track formation significantly alters dry soil microbial communities, likely influencing subsequent ecosystem functioning. We highlight how Dry Valley water tracks could be a useful model system for understanding the potential habitability of transiently wetted environments found on the surface of Mars.

}, keywords = {LTER-MCM, Antarctica, extremophiles, Mars analog, microbial ecology, water tracks}, doi = {10.3389/fmicb.2021.616730}, url = {https://www.frontiersin.org/articles/10.3389/fmicb.2021.616730}, author = {George, Scott F. and Noah Fierer and Joseph S. Levy and Byron Adams} } @inbook {4581, title = {Chemical weathering in the McMurdo Dry Valleys, Antarctica}, booktitle = {Hydrogeology, Chemical Weathering, and Soil Formation}, series = {Geophysical Monograph Series}, number = {257}, year = {2021}, pages = {205-216}, publisher = {John Wiley \& Sons, Inc.}, organization = {John Wiley \& Sons, Inc.}, chapter = {11}, address = {Hoboken, NJ}, abstract = {

While chemical weathering has not always been considered an active process in the McMurdo Dry Valleys (MDV), Antarctica, long-term geochemical and hydrological investigations have provided an overall better understanding of chemical weathering in this polar desert environment. Liquid water on the landscape is limited to stream channels as well as shallow subsurface melt features, as there is no overland flow. Stream total suspended sediment loads are low, with the sources of sediment from stream channels, aeolian input, and/or from the surfaces of glaciers. MDV soils contain high concentrations of soluble salts with little clay material, but since absent of water, these soils are a minimal location of chemical weathering. Hyporheic zones exchange water during streamflow, and these areas control the stream geochemistry over various temporal scales. Hyporheic zones promote rapid aluminosilicate weathering by moving dilute glacial meltwater into intimate contact with sediment surfaces. Rapid weathering of the aluminosilicates in the streambed and hyporheic zones is the most plausible explanation for chemostasis observed in these streams, indicating that little to no catchment processes are necessary to explain the observed chemostasis in the MDV. Shallow subsurface waters with distinct geochemical signatures have much higher dissolved Si concentrations than the stream waters and indicate that they are responsible for enhanced aluminosilicate weathering in this polar desert environment. The dissolution of CaCO3 is also a major process in the hyporheic zones as generally the streams are unsaturated with respect to calcite. Cation-exchange reactions are also important in the evolution from Na-Cl brines to Ca-Cl brines within the soil column, while authigenic CaCO3 can both dissolve and precipitate depending on the condition of the system. Recently, stream channel landscapes are changing due to the melting of buried ice, creating thermokarst and water track features, resulting in a sediment and solute influx to the stream.

}, keywords = {LTER-MCM, aluminosilicate weathering, CaCO3 dissolution/precipitation, chemical weathering, hyporheic zone, McMurdo Dry Valleys}, doi = {10.1002/9781119563952.ch11}, url = {https://agupubs.onlinelibrary.wiley.com/doi/10.1002/9781119563952.ch11}, author = {W. Berry Lyons and Leslie, Deborah L. and Michael N. Gooseff}, editor = {Hunt, Allen and Egli, Markus and Faybishenko, Boris} } @article {4636, title = {Exploring the boundaries of microbial habitability in soil}, journal = {Journal of Geophysical Research: Biogeosciences}, volume = {126}, year = {2021}, month = {06/2021}, abstract = {

Microbes are widely assumed to be capable of colonizing even the most challenging terrestrial surface environments on Earth given enough time. We would not expect to find surface soils uninhabited by microbes as soils typically harbor diverse microbial communities and viable microbes have been detected in soils exposed to even the most inhospitable conditions. However, if uninhabited soils do exist, we might expect to find them in Antarctica. We analyzed 204 ice-free soils collected from across a remote valley in the Transantarctic Mountains (84\–85\°S, 174\–177\°W) and were able to identify a potential limit of microbial habitability. While most of the soils we tested contained diverse microbial communities, with fungi being particularly ubiquitous, microbes could not be detected in many of the driest, higher elevation soils\—results that were confirmed using cultivation-dependent, cultivation-independent, and metabolic assays. While we cannot confirm that this subset of soils is completely sterile and devoid of microbial life, our results suggest that microbial life is severely restricted in the coldest, driest, and saltiest Antarctic soils. Constant exposure to these conditions for thousands of years has limited microbial communities so that their presence and activity is below detectable limits using a variety of standard methods. Such soils are unlikely to be unique to the studied region with this work supporting previous hypotheses that microbial habitability is constrained by near-continuous exposure to cold, dry, and salty conditions, establishing the environmental conditions that limit microbial life in terrestrial surface soils.

}, keywords = {LTER-MCM, Antarctica, astrobiology, bacteria, extremophiles, fungi, soils}, issn = {2169-8953}, doi = {10.1029/2020JG006052}, url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JG006052}, author = {Dragone, Nicholas B. and Melisa A. Diaz and Hogg, Ian D. and W. Berry Lyons and W. Andrew Jackson and Diana H. Wall and Adams, Byron J. and Noah Fierer} } @article {4583, title = {Genome analysis of Plectus murrayi, a nematode from continental Antarctica}, journal = {G3 Genes|Genomes|Genetics}, year = {2021}, month = {01/2021}, abstract = {

Plectus murrayi is one of the most common and locally abundant invertebrates of continental Antarctic ecosystems. Because it is readily cultured on artificial medium in the laboratory and highly tolerant to an extremely harsh environment, Plectus murrayi is emerging as a model organism for understanding the evolutionary origin and maintenance of adaptive responses to multiple environmental stressors, including freezing and desiccation. The de novo assembled genome of Plectus murrayi contains 225.741 million base pairs and a total of 14,689 predicted genes. Compared to Caenorhabditis elegans, the architectural components of Plectus murrayi are characterized by a lower number of protein-coding genes, fewer transposable elements, but more exons, than closely related taxa from less harsh environments. We compared the transcriptomes of lab-reared Plectus murrayi with wild-caught Plectus murrayi and found genes involved in growth and cellular processing were up-regulated in lab-cultured Plectus murrayi, while a few genes associated with cellular metabolism and freeze tolerance were expressed at relatively lower levels. Preliminary comparative genomic and transcriptomic analyses suggest that the observed constraints on P. murrayi genome architecture and functional gene expression, including genome decay and intron retention, may be an adaptive response to persisting in a biotically simplified, yet consistently physically harsh environment.

}, keywords = {LTER-MCM, gene loss, genome architecture, genome assembly, genome decay, Plectus murrayi}, doi = {10.1093/g3journal/jkaa045}, url = {https://academic.oup.com/g3journal/advance-article/doi/10.1093/g3journal/jkaa045/6044189}, author = {Xue, Xia and Suvorov, Anton and Fujimoto, Stanley and Dilman, Adler R. and Byron Adams} } @article {4646, title = {Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica}, journal = {Biogeosciences}, volume = {18}, year = {2021}, month = {03/2021}, pages = {1629 - 1644}, abstract = {

Previous studies have established links between biodiversity and soil geochemistry in the McMurdo Dry Valleys, Antarctica, where environmental gradients are important determinants of soil biodiversity. However, these gradients are not well established in the central Transantarctic Mountains, which are thought to represent some of the least hospitable Antarctic soils. We analyzed 220 samples from 11 ice-free areas along the Shackleton Glacier (~85\°S), a major outlet glacier of the East Antarctic Ice Sheet. We established three zones of distinct geochemical gradients near the head of the glacier (upper), its central part (middle), and at the mouth (lower). The upper zone had the highest water-soluble salt concentrations with total salt concentrations exceeding 80 000 \µg g-1, while the lower zone had the lowest water-soluble N:P ratios, suggesting that, in addition to other parameters (such as proximity to water and/or ice), the lower zone likely represents the most favorable ecological habitats. Given the strong dependence of geochemistry on geographic parameters, we developed multiple linear regression and random forest models to predict soil geochemical trends given latitude, longitude, elevation, distance from the coast, distance from the glacier, and soil moisture (variables which can be inferred from remote measurements). Confidence in our random forest model predictions was moderately high with R2 values for total water-soluble salts, water-soluble N:P, ClO4-, and ClO3- of 0.81, 0.88, 0.78, and 0.74, respectively. These modeling results can be used to predict geochemical gradients and estimate salt concentrations for other Transantarctic Mountain soils, information that can ultimately be used to better predict distributions of soil biota in this remote region.

}, keywords = {LTER-MCM}, doi = {10.5194/bg-18-1629-2021}, url = {https://bg.copernicus.org/articles/18/1629/2021/}, author = {Melisa A. Diaz and Christopher B. Gardner and Welch, Susan A. and W. Andrew Jackson and Adams, Byron J. and Diana H. Wall and Hogg, Ian D. and Noah Fierer and W. Berry Lyons} } @article {4643, title = {Long-term shifts in feedbacks among glacier surface change, melt generation, and runoff, McMurdo Dry Valleys, Antarctica}, journal = {Hydrological Processes}, year = {2021}, month = {07/2021}, abstract = {

Glaciers of the McMurdo Dry Valleys (MDVs) Antarctica are the main source of streamflow in this polar desert. Because summer air temperatures hover near 0\°C small changes in the energy balance strongly affect meltwater generation. Here we demonstrate that increased surface roughness, which alters the turbulent transfer of energy between the ice surface and atmosphere, yields a detectable increase in meltwater runoff. At low elevations on the glaciers, basin-like topography became significantly rougher over 13\ years between repeat lidar surveys, yielding greater melt. In contrast, the smoother ice at higher elevation exhibited no detectable change in roughness. We pose a conceptual model of the cycle of glacier surface change as a result of climate forcing whereby glacier surfaces transition from being dominated by sublimation to becoming increasingly melt-dominated, which is reversible under prolonged cool periods. This research advances our understanding of warm season effects on polar glaciers.

}, keywords = {LTER-MCM}, issn = {0885-6087}, doi = {10.1002/hyp.14292}, url = {https://onlinelibrary.wiley.com/doi/10.1002/hyp.14292}, author = {Bergstrom, Anna J. and Michael N. Gooseff and Andrew G Fountain and Hoffman, Matthew} } @article {4768, title = {Patterns and trends of organic matter processing and transport: Insights from the US Long-term Ecological Research Network}, journal = {Climate Change Ecology}, volume = {2}, year = {2021}, month = {12/2021}, pages = {100025}, abstract = {

Organic matter (OM) dynamics determine how much carbon is stored in ecosystems, a service that modulates climate. We synthesized research from across the US Long-Term Ecological Research (LTER) Network to assemble a conceptual model of OM dynamics that is consistent with inter-disciplinary perspectives and emphasizes vulnerability of OM pools to disturbance. Guided by this conceptual model, we identified unanticipated patterns and long-term trends in processing and transport of OM emerging from terrestrial, freshwater, wetland, and marine ecosystems. Cross-ecosystem synthesis combined with a survey of researchers revealed several themes: 1) strong effects of climate change on OM dynamics, 2) surprising patterns in OM storage and dynamics resulting from coupling with nutrients, 3) characteristic and often complex legacies of land use and disturbance, 4) a significant role of OM transport that is often overlooked in terrestrial ecosystems, and 5) prospects for reducing uncertainty in forecasting OM dynamics by incorporating the chemical composition of OM. Cross-fertilization of perspectives and approaches across LTER sites and other research networks can stimulate the comprehensive understanding required to support large-scale characterizations of OM budgets and the role of ecosystems in regulating global climate.

}, keywords = {LTER-MCM, coupled biogeochemical cycles, cross-site synthesis, organic matter composition, organic matter storage, stabilization, transport}, issn = {26669005}, doi = {10.1016/j.ecochg.2021.100025}, url = {https://www.sciencedirect.com/science/article/pii/S2666900521000253}, author = {Harms, Tamara K. and Groffman, Peter M. and Aluwihare, Lihini and Craft, Christopher and Wieder, William R and Hobbie, S and Baer, Sara G. and J.M. Blair and Frey, Serita D. and Remucal, Christina K. and Rudgers, Jennifer A. and Collins, SL and Kominoski, John S. and Ball, Becky and John C. Priscu and John E. Barrett} } @article {4715, title = {Research sites get closer to field camps over time: Informing environmental management through a geospatial analysis of science in the McMurdo Dry Valleys, Antarctica}, journal = {PLOS ONE}, volume = {16}, year = {2021}, month = {11/2021}, pages = {e0257950}, abstract = {

As in many parts of the world, the management of environmental science research in Antarctica relies on cost-benefit analysis of negative environmental impact versus positive scientific gain. Several studies have examined the environmental impact of Antarctic field camps, but very little work looks at how the placement of these camps influences scientific research. In this study, we integrate bibliometrics, geospatial analysis, and historical research to understand the relationship between field camp placement and scientific production in the McMurdo Dry Valleys of East Antarctica. Our analysis of the scientific corpus from 1907\–2016 shows that, on average, research sites have become less dispersed and closer to field camps over time. Scientific output does not necessarily correspond to the number of field camps, and constructing a field camp does not always lead to a subsequent increase in research in the local area. Our results underscore the need to consider the complex historical and spatial relationships between field camps and research sites in environmental management decision-making in Antarctica and other protected areas.

}, keywords = {LTER-MCM}, doi = {10.1371/journal.pone.0257950}, url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0257950}, author = {Chignell, Stephen M. and Myers, Madeline and Howkins, Adrian and Andrew G Fountain} } @article {4647, title = {Thermal legacy of a large paleolake in Taylor Valley, East Antarctica, as evidenced by an airborne electromagnetic survey}, journal = {The Cryosphere}, volume = {15}, year = {2021}, month = {08/2021}, pages = {3577 - 3593}, abstract = {

Previous studies of the lakes of the McMurdo Dry Valleys have attempted to constrain lake level history, and results suggest the lakes have undergone hundreds of meters of lake level change within the last 20 000 years. Past studies have utilized the interpretation of geologic deposits, lake chemistry, and ice sheet history to deduce lake level history; however a substantial amount of disagreement remains between the findings, indicating a need for further investigation using new techniques. This study utilizes a regional airborne resistivity survey to provide novel insight into the paleohydrology of the region. Mean resistivity maps revealed an extensive brine beneath the Lake Fryxell basin, which is interpreted as a legacy groundwater signal from higher lake levels in the past. Resistivity data suggest that active permafrost formation has been ongoing since the onset of lake drainage and that as recently as 1500\–4000 years BP, lake levels were over 60 m higher than present. This coincides with a warmer-than-modern paleoclimate throughout the Holocene inferred by the nearby Taylor Dome ice core record. Our results indicate Mid to Late Holocene lake level high stands, which runs counter to previous research finding a colder and drier era with little hydrologic activity throughout the last 5000 years.

}, keywords = {LTER-MCM}, doi = {10.5194/tc-15-3577-2021}, url = {https://tc.copernicus.org/articles/15/3577/2021/}, author = {Myers, Krista F. and Peter T. Doran and Tulaczyk, Slawek M. and Foley, Neil T. and Bording, Thue S. and Auken, Esben and Hilary A. Dugan and Jill A. Mikucki and Foged, Nikolaj and Grombacher, Denys and Ross A. Virginia} } @article {4448, title = {Climate from the McMurdo Dry Valleys, Antarctica, 1986 {\textendash} 2017: Surface air temperature trends and redefined summer season}, journal = {Journal of Geophysical Research: Atmospheres}, year = {2020}, month = {05/2020}, abstract = {

The weather of the McMurdo Dry Valleys, Antarctica, the largest ice-free region of the Antarctica, has been continuously monitored since 1985 with currently 14 operational meteorological stations distributed throughout the valleys. Because climate is based on a 30-year record of weather, this is the first study to truly define the contemporary climate of the McMurdo Dry Valleys. Mean air temperature and solar radiation based on all stations were -20\°C and 102 W m-2, respectively. Depending on the site location, the mean annual air temperatures on the valleys floors ranged between -15\°C and -30\°C, and mean annual solar radiation varied between 72 W m-2 and 122 W m-2. Surface air temperature decreased by 0.7\°C per decade from 1986 to 2006 at Lake Hoare station (longest continuous record), after which the record is highly variable with no trend. All stations with sufficiently long records showed similar trend shifts in 2005 \±1 year. Summer is defined as November through February, using a physically based process: up-valley warming from the coast associated with a change in atmospheric stability.

}, keywords = {LTER-MCM, McMurdo Dry Valleys, summer season, weather observations}, doi = {10.1029/2019JD032180}, url = {https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019JD032180}, author = {Obryk, M. K. and Doran, P. T. and Fountain, A. G. and Myers, M. and McKay, C. P.} } @article {4438, title = {A digital archive of human activity in the McMurdo Dry Valleys, Antarctica}, journal = {Earth System Science Data}, volume = {12}, year = {2020}, month = {05/2020}, abstract = {

Over the last half century, the McMurdo Dry Valleys (MDV) of East Antarctica have become a globally important site for scientific research and environmental monitoring. Historical data can make important contributions to current research activities and environmental management in Antarctica but tend to be widely scattered and difficult to access. We address this need in the MDV by compiling over 5000 historical photographs, sketches, maps, oral interviews, publications, and other archival resources into an online digital archive. The data have been digitized and georeferenced using a standardized metadata structure, which enables intuitive searches and data discovery via an online interface. The ultimate aim of the archive is to create as comprehensive as possible a record of human activity in the MDV to support ongoing research, management, and conservation efforts. This is a valuable tool for scientists seeking to understand the dynamics of change in lakes, glaciers, and other physical systems, as well as humanistic inquiry into the history of the Southern Continent. In addition to providing benchmarks for understanding change over time, the data can help target field sampling for studies working under the assumption of a pristine landscape by enabling researchers to identify the date and extent of past human activities. The full database is accessible via a web browser-based interface hosted by the McMurdo Long Term Ecological Research site: http://mcmurdohistory.lternet.edu/ (last access: 5 May 2020). The complete metadata data for all resources in the database are also available at the Environmental Data Initiative: https://doi.org/10.6073/pasta/6744cb28a544fda827805db123d36557 (Howkins et al., 2019).

}, keywords = {LTER-MCM}, doi = {10.5194/essd-12-1117-2020}, url = {https://www.earth-syst-sci-data.net/12/1117/2020/}, author = {Howkins, Adrian and Chignell, Stephen M. and Gullett, Poppie and Andrew G Fountain and Brett, Melissa and Preciado, Evelin} } @mastersthesis {4451, title = {Glacial meltwater modeling to simulate lake water budget (1996-2013) in Taylor Valley, Antarctica}, volume = {M.S.}, year = {2020}, month = {01/2020}, school = {Portland State University}, type = {masters}, address = {Portland, OR}, abstract = {

The McMurdo Dry Valleys (MDV), the largest ice-free region (4,500 km2) in Antarctica, are a polar desert with an average annual temperature of -18 ̊C. In Taylor Valley, one of the MDV, closed-basin, perennially ice-covered lakes occupy the valley floor. Their water balance is controlled by inflow from glacial meltwater runoff and loss due to sublimation, making them sensitive indicators of climate. In this study, a physically-based model of glacier meltwater and lake ice sublimation is adapted to explain modern (1996 to 2013) lake-level variations. Meltwater model results were improved by the inclusion of MODIS remotely-sensed albedo measurements (E = 0.47; nRMSE = 0.73). After 2008 the meltwater model significantly under-predicted streamflow and only through decreasing albedo by -30\% (equivalent to a decrease of -0.18 on average) did the results match observations (E = 0.79; nRMSE = 0.45). This study provides the first estimate of direct (unmeasured) glacier inflow to the lakes, 69\%, 73\% and 28\%, and sublimation loss rates, 0.37 m yr-1, 0.24 m yr-1 and 0.16 m yr-1, for Lakes Bonney, Hoare and Fryxell, respectively. Despite similar meltwater volumes entering Lakes Bonney and Fryxell, the difference in basin hypsometry results in a much faster lake rise at Bonney from 2002-13. If future climate conditions match current (1996-2013) conditions, all lakes will rise through the end of the century.

}, keywords = {LTER-MCM}, doi = {10.15760/etd.7237}, url = {https://archives.pdx.edu/ds/psu/30806}, author = {Cross, Julian M. and Andrew G Fountain} } @article {4420, title = {A global database of soil nematode abundance and functional group composition}, journal = {Scientific Data}, volume = {7}, year = {2020}, month = {03/2020}, abstract = {

As the most abundant animals on earth, nematodes are a dominant component of the soil community. they play critical roles in regulating biogeochemical cycles and vegetation dynamics within and across landscapes and are an indicator of soil biological activity. Here,\ we present a comprehensive global dataset of soil nematode abundance and functional group composition. This dataset includes 6,825 georeferenced soil samples from all continents and biomes. For geospatial mapping purposes these samples are aggregated into 1,933 unique 1-km pixels, each of which is linked to 73 global environmental covariate data layers. Altogether,\ this dataset can help to gain insight into the spatial distribution patterns of soil nematode abundance and community composition, and the environmental drivers shaping these patterns.

}, keywords = {LTER-MCM}, doi = {10.1038/s41597-020-0437-3}, url = {https://www.nature.com/articles/s41597-020-0437-3}, author = {van den Hoogen, Johan and Geisen, Stefan and Diana H. Wall and Wardle, D and Traunspurger, Walter and de Goede, Ron G. M. and Byron Adams and Ahmad, Wasim and Ferris, Howard and Richard D. Bardgett and Bonkowski, Michael and Campos-Herrera, Raquel and Cares, Juvenil E. and Caruso, Tancredi and de Brito Caixeta, Larissa and Chen, Xiaoyun and Costa, Sofia R. and Creamer, Rachel and da Cunha e Castro, Jos{\'e} and Dam, Marie and Djigal, Djibril and Escuer, Miguel and Griffiths, Bryan S. and Guti{\'e}rrez, Carmen and Hohberg, Karin and Kalinkina, Daria and Kardol, Paul and Kergunteuil, Alan and Korthals, Gerard and Krashevska, Valentyna and Kudrin, Alexey A. and Li, Qi and Liang, Wenju and Magilton, Matthew and Marais, Mariette and Mart{\'\i}n, Jos{\'e} Antonio Rodr{\'\i}guez and Matveeva, Elizaveta and Mayad, El Hassan and Mzough, E. and Mulder, Christian and Mullin, Peter and Neilson, Roy and Nguyen, T. A. Duong and Uffe N. Nielsen and Okada, Hiroaki and Rius, Juan Emilio Palomares and Pan, Kaiwen and Peneva, Vlada and Pellissier, Lo{\"\i}c and Carlos Pereira da Silva, Julio and Pitteloud, Camille and Powers, Thomas O. and Powers, Kirsten and Quist, Casper W. and Rasmann, Sergio and Moreno, Sara S{\'a}nchez and Scheu, Stefan and Set{\"a}l{\"a}, Heikki and Sushchuk, Anna and Tiunov, Alexei V. and Trap, Jean and Vesterg{\r a}rd, Mette and Villenave, Cecile and Waeyenberge, Lieven and Wilschut, Rutger and Wright, Daniel G. and Keith, Aidan M. and Yang, Jiue-in and Schmidt, Olaf and Bouharroud, R. and Ferji, Z. and van der Putten, Wim H. and Routh, Devin and Crowther, Thomas Ward} } @article {4374, title = {The polar regions in a 2{\textdegree}C warmer world}, journal = {Science Advances}, volume = {5}, year = {2019}, month = {12/2019}, pages = {eaaw9883}, abstract = {

Over the past decade, the Arctic has warmed by 0.75\°C, far outpacing the global average, while Antarctic tem- peratures have remained comparatively stable. As Earth approaches 2\°C warming, the Arctic and Antarctic may reach 4\°C and 2\°C mean annual warming, and 7\°C and 3\°C winter warming, respectively. Expected consequences of increased Arctic warming include ongoing loss of land and sea ice, threats to wildlife and traditional human livelihoods, increased methane emissions, and extreme weather at lower latitudes. With low biodiversity, Antarctic ecosystems may be vulnerable to state shifts and species invasions. Land ice loss in both regions will contribute substantially to global sea level rise, with up to 3 m rise possible if certain thresholds are crossed. Mitigation efforts can slow or reduce warming, but without them northern high latitude warming may accelerate in the next two to four decades. International cooperation will be crucial to foreseeing and adapting to expected changes.

}, keywords = {LTER-MCM}, doi = {10.1126/sciadv.aaw9883}, url = {http://advances.sciencemag.org/lookup/doi/10.1126/sciadv.aaw9883}, author = {Post, Eric and Alley, Richard B. and Christensen, Torben R. and Macias-Fauria, Marc and Forbes, Bruce C. and Michael N. Gooseff and Iler, Amy and Kerby, Jeffrey T. and Laidre, Kristin L. and Mann, Michael E. and Olofsson, Johan and Stroeve, Julienne C. and Ulmer, Fran and Ross A. Virginia and Wang, Muyin} } @article {4295, title = {Soil nematode abundance and functional group composition at a global scale}, journal = {Nature}, volume = {572}, year = {2019}, month = {08/2019}, abstract = {

Soil organisms are a crucial part of the terrestrial biosphere. Despite their importance for ecosystem functioning, few quantitative, spatially explicit models of the active belowground community currently exist. In particular, nematodes are the most abundant animals on Earth, filling all trophic levels in the soil food web. Here we use 6,759 georeferenced samples to generate a mechanistic understanding of the patterns of the global abundance of nematodes in the soil and the composition of their functional groups. The resulting maps show that 4.4 \± 0.64 \× 1020 nematodes (with a total biomass of approximately 0.3 gigatonnes) inhabit surface soils across the world, with higher abundances in sub-Arctic regions (38\% of total) than in temperate (24\%) or tropical (21\%) regions. Regional variations in these global trends also provide insights into local patterns of soil fertility and functioning. These high-resolution models provide the first steps towards representing soil ecological processes in global biogeochemical models and will enable the prediction of elemental cycling under current and future climate scenarios.

}, keywords = {LTER-MCM}, doi = {10.1038/s41586-019-1418-6}, url = {https://www.nature.com/articles/s41586-019-1418-6}, author = {van den Hoogen, Johan and Geisen, Stefan and Routh, Devin and Ferris, Howard and Traunspurger, Walter and Wardle, D and de Goede, Ron G. M. and Byron Adams and Ahmad, Wasim and Andriuzzi, Walter S. and Richard D. Bardgett and Bonkowski, Michael and Campos-Herrera, Raquel and Cares, Juvenil E. and Caruso, Tancredi and de Brito Caixeta, Larissa and Chen, Xiaoyun and Costa, Sofia R. and Creamer, Rachel and Mauro da Cunha Castro, Jos{\'e} and Dam, Marie and Djigal, Djibril and Escuer, Miguel and Griffiths, Bryan S. and Guti{\'e}rrez, Carmen and Hohberg, Karin and Kalinkina, Daria and Kardol, Paul and Kergunteuil, Alan and Korthals, Gerard and Krashevska, Valentyna and Kudrin, Alexey A. and Li, Qi and Liang, Wenju and Magilton, Matthew and Marais, Mariette and Mart{\'\i}n, Jos{\'e} Antonio Rodr{\'\i}guez and Matveeva, Elizaveta and Mayad, El Hassan and Mulder, Christian and Mullin, Peter and Neilson, Roy and Nguyen, T. A. Duong and Uffe N. Nielsen and Okada, Hiroaki and Rius, Juan Emilio Palomares and Pan, Kaiwen and Peneva, Vlada and Pellissier, Lo{\"\i}c and Carlos Pereira da Silva, Julio and Pitteloud, Camille and Powers, Thomas O. and Powers, Kirsten and Quist, Casper W. and Rasmann, Sergio and Moreno, Sara S{\'a}nchez and Scheu, Stefan and Set{\"a}l{\"a}, Heikki and Sushchuk, Anna and Tiunov, Alexei V. and Trap, Jean and van der Putten, W and Vesterg{\r a}rd, Mette and Villenave, Cecile and Waeyenberge, Lieven and Diana H. Wall and Wilschut, Rutger and Wright, Daniel G. and Yang, Jiue-in and Crowther, Thomas Ward} } @article {4159, title = {BioTIME: A database of biodiversity time series for the Anthropocene}, journal = {Global Ecology and Biogeography}, volume = {27}, year = {2018}, month = {07/2018}, pages = {760-786}, abstract = {

Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.

Main types of variables included: The database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.

Spatial location and grain: BioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2). Time period and grain BioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.

Major taxa and level of measurement:\ BioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.

Software format: .csv and .SQL.

}, keywords = {LTER-MCM, biodiversity, global, spatial, species richness, temporal, turnover}, doi = {10.1111/geb.12729}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/geb.12729}, author = {Dornelas, Maria and Ant{\~a}o, Laura H. and Moyes, Faye and Bates, Amanda E. and Magurran, Anne E. and Adam, Du{\v s}an and Akhmetzhanova, Asem A. and Appeltans, Ward and Arcos, Jos{\'e} Manuel and Arnold, Haley and Ayyappan, Narayanan and Badihi, Gal and Baird, Andrew H. and Barbosa, Miguel and Barreto, Tiago Egydio and B{\"a}ssler, Claus and Bellgrove, Alecia and Belmaker, Jonathan and Benedetti-Cecchi, Lisandro and Bett, Brian J. and Bjorkman, Anne D. and B{\l}a{\.z}ewicz, Magdalena and Blowes, Shane A. and Bloch, Christopher P. and Bonebrake, Timothy C. and Boyd, Susan and Bradford, Matt and Brooks, Andrew J. and Brown, James H. and Bruelheide, Helge and Budy, Phaedra and Carvalho, Fernando and Casta{\~n}eda-Moya, Edward and Chen, Chaolun Allen and Chamblee, John F. and Chase, Tory J. and Siegwart Collier, Laura and Collinge, Sharon K. and Condit, Richard and Cooper, Elisabeth J. and Cornelissen, J. Hans C. and Cotano, Unai and Kyle Crow, Shannan and Damasceno, Gabriella and Davies, Claire H. and Davis, Robert A. and Day, Frank P. and Degraer, Steven and Doherty, Tim S. and Dunn, Timothy E. and Durigan, Giselda and Duffy, J. Emmett and Edelist, Dor and Edgar, Graham J. and Elahi, Robin and Elmendorf, Sarah C. and Enemar, Anders and Ernest, S. K. Morgan and Escribano, Rub{\'e}n and Estiarte, Marc and Evans, Brian S. and Fan, Tung-Yung and Turini Farah, Fabiano and Loureiro Fernandes, Luiz and Farneda, F{\'a}bio Z. and Fidelis, Alessandra and Fitt, Robert and Fosaa, Anna Maria and Daher Correa Franco, Geraldo Antonio and Frank, Grace E. and Fraser, William R. and Garc{\'\i}a, Hernando and Cazzolla Gatti, Roberto and Givan, Or and Gorgone-Barbosa, Elizabeth and Gould, William A. and Gries, Corinna and Grossman, Gary D. and Gutierr{\'e}z, Julio R. and Hale, Stephen and Harmon, Mark E. and Harte, John and Haskins, Gary and Henshaw, Donald L. and Hermanutz, Luise and Hidalgo, Pamela and Higuchi, Pedro and Hoey, Andrew and Van Hoey, Gert and Hofgaard, Annika and Holeck, Kristen and Hollister, Robert D. and Holmes, Richard and Hoogenboom, Mia and Hsieh, Chih-hao and Hubbell, Stephen P. and Huettmann, Falk and Huffard, Christine L. and Hurlbert, Allen H. and Macedo Ivanauskas, Nat{\'a}lia and Jan{\'\i}k, David and Jandt, Ute and Ja{\.z}d{\.z}ewska, Anna and Johannessen, Tore and Johnstone, Jill and Jones, Julia and Jones, Faith A. M. and Kang, Jungwon and Kartawijaya, Tasrif and Keeley, Erin C. and Kelt, Douglas A. and Kinnear, Rebecca and Klanderud, Kari and Knutsen, Halvor and Koenig, Christopher C. and Kortz, Alessandra R. and Kr{\'a}l, Kamil and Kuhnz, Linda A. and Kuo, Chao-Yang and Kushner, David J. and Laguionie-Marchais, Claire and Lancaster, Lesley T. and Min Lee, Cheol and Lefcheck, Jonathan S. and L{\'e}vesque, Esther and Lightfoot, David and Lloret, Francisco and Lloyd, John D. and L{\'o}pez-Baucells, Adri{\`a} and Louzao, Maite and Madin, Joshua S. and Magn{\'u}sson, Borg{\th}{\'o}r and Malamud, Shahar and Matthews, Iain and McFarland, Kent P. and McGill, Brian and Diane M. McKnight and McLarney, William O. and Meador, Jason and Meserve, Peter L. and Metcalfe, Daniel J. and Meyer, Christoph F. J. and Michelsen, Anders and Milchakova, Nataliya and Moens, Tom and Moland, Even and Moore, Jon and Mathias Moreira, Carolina and M{\"u}ller, J{\"o}rg and Murphy, Grace and Myers-Smith, Isla H. and Myster, Randall W. and Naumov, Andrew and Neat, Francis and Nelson, James A. and Paul Nelson, Michael and Newton, Stephen F. and Norden, Natalia and Oliver, Jeffrey C. and Olsen, Esben M. and Onipchenko, Vladimir G. and Pabis, Krzysztof and Pabst, Robert J. and Paquette, Alain and Pardede, Sinta and Paterson, David M. and P{\'e}lissier, Rapha{\"e}l and Pe{\~n}uelas, Josep and P{\'e}rez-Matus, Alejandro and Pizarro, Oscar and Pomati, Francesco and Post, Eric and Prins, Herbert H. T. and John C. Priscu and Provoost, Pieter and Prudic, Kathleen L. and Pulliainen, Erkki and Ramesh, B. R. and Mendivil Ramos, Olivia and Rassweiler, Andrew and Rebelo, Jose Eduardo and Reed, Daniel C. and Reich, Peter B. and Remillard, Suzanne M. and Richardson, Anthony J. and Richardson, J. Paul and van Rijn, Itai and Rocha, Ricardo and Rivera-Monroy, Victor H. and Rixen, Christian and Robinson, Kevin P. and Ribeiro Rodrigues, Ricardo and de Cerqueira Rossa-Feres, Denise and Rudstam, Lars and Ruhl, Henry and Ruz, Catalina S. and Sampaio, Erica M. and Rybicki, Nancy and Rypel, Andrew and Sal, Sofia and Salgado, Beatriz and Santos, Flavio A. M. and Savassi-Coutinho, Ana Paula and Scanga, Sara and Schmidt, Jochen and Schooley, Robert and Setiawan, Fakhrizal and Shao, Kwang-Tsao and Shaver, Gaius R. and Sherman, Sally and Sherry, Thomas W. and Sici{\'n}ski, Jacek and Sievers, Caya and da Silva, Ana Carolina and Rodrigues da Silva, Fernando and Silveira, Fabio L. and Slingsby, Jasper and Smart, Tracey and Snell, Sara J. and Soudzilovskaia, Nadejda A. and Souza, Gabriel B. G. and Maluf Souza, Flaviana and Castro Souza, Vin{\'\i}cius and Stallings, Christopher D. and Stanforth, Rowan and Stanley, Emily H. and Mauro Sterza, Jos{\'e} and Stevens, Maarten and Stuart-Smith, Rick and Rondon Suarez, Yzel and Supp, Sarah} } @article {4105, title = {Dissolved Trace and Minor Elements in Cryoconite Holes and Supraglacial Streams, Canada Glacier, Antarctica}, journal = {Frontiers in Earth Science}, volume = {6}, year = {2018}, month = {04/2018}, abstract = {

We present a synthesis of the trace element chemistry in melt on the surface Canada Glacier, Taylor Valley, McMurdo Dry Valleys (MDV), Antarctica (\∼78{\textopenbullet}S). The MDV is largely ice-free. Low accumulation rates, strong winds, and proximity to the valley floor make these glaciers dusty in comparison to their inland counterparts. This study examines both supraglacial melt streams and cryoconite holes. Supraglacial streams on the lower Canada Glacier have median dissolved (\<0.4\ μm) concentrations of Fe, Mn, As, Cu, and V of 71.5, 75.5, 3.7, 4.6, and 4.3 nM. All dissolved Cd concentrations and the vast majority of Pb values are below our analytical detection (i.e., 0.4 and 0.06 nM). Chemical behavior did not follow similar trends for eastern and western draining waters. Heterogeneity likely reflects distinctions eolian deposition, rock:water ratios, and hydrologic connectivity. Future increases in wind-delivered sediment will likely drive dynamic responses in melt chemistry. For elements above detection limits, dissolved concentrations in glacier surface melt are within an order of magnitude of concentrations observed in proglacial streams (i.e., flowing on the valley floor). The Fe enrichment of cryoconite water relative to N, P, or Si exceeds enrichment observed in marine phytoplankton. This suggests that the glacier surface is an important source of Fe to downstream ecosystems.

}, keywords = {LTER-MCM, Antarctica, cryoconite holes, glacier melt chemistry, supraglacial streams, trace elements}, doi = {10.3389/feart.2018.00031}, url = {http://journal.frontiersin.org/article/10.3389/feart.2018.00031/full}, author = {Sarah Fortner and W. Berry Lyons} } @article {4079, title = {Drivers of solar radiation variability in the McMurdo Dry Valleys, Antarctica}, journal = {Scientific Reports}, volume = {8}, year = {2018}, month = {03/2018}, abstract = {

Annually averaged solar radiation in the McMurdo Dry Valleys, Antarctica has varied by over 20 W m\−2 during the past three decades; however, the drivers of this variability are unknown. Because small differences in radiation are important to water availability and ecosystem functioning in polar deserts, determining the causes are important to predictions of future desert processes. We examine the potential drivers of solar variability and systematically eliminate all but stratospheric sulfur dioxide. We argue that increases in stratospheric sulfur dioxide increase stratospheric aerosol optical depth\ and decrease solar intensity. Because of the polar location of the McMurdo Dry Valleys (77\–78\°S) and relatively long solar ray path through the stratosphere, terrestrial solar intensity is sensitive to small differences in stratospheric transmissivity. Important sources of sulfur dioxide include natural (wildfires and volcanic eruptions) and anthropogenic emission.

}, keywords = {LTER-MCM}, doi = {10.1038/s41598-018-23390-7}, url = {http://www.nature.com/articles/s41598-018-23390-7.pdf}, author = {Maciek K. Obryk and Andrew G Fountain and Peter T. Doran and W. Berry Lyons and Eastman, R.} } @article {4136, title = {Local and Regional Scale Heterogeneity Drive Bacterial Community Diversity and Composition in a Polar Desert}, journal = {Frontiers in Microbiology}, volume = {9}, year = {2018}, month = {08/2018}, abstract = {

The distribution of organisms in an environment is neither uniform nor random but is instead spatially patterned. The factors that control this patterning are complex and the underlying mechanisms are poorly understood. Soil microbes are critical to ecosystem function but exhibit highly complex distributions and community dynamics due in large part to the scale-dependent effects of environmental heterogeneity. To better understand the impact of environmental heterogeneity on the distribution of soil microbes, we sequenced the 16S rRNA gene from bacterial communities in the microbe-dominated polar desert ecosystem of the McMurdo Dry Valleys (MDV), Antarctica. Significant differences in key edaphic variables and alpha diversity were observed among the three lake basins of the Taylor Valley (Kruskal\–Wallis; pH: χ2 = 68.89, P \< 0.001, conductivity: χ2 = 35.03, P \< 0.001, observed species: χ2 = 7.98, P = 0.019 and inverse Simpson: χ2 = 18.52, P \< 0.001) and each basin supported distinctive microbial communities (ANOSIM R = 0.466, P = 0.001, random forest ratio of 14.1). However, relationships between community structure and edaphic characteristics were highly variable and contextual, ranging in magnitude and direction across regional, basin, and local scales. Correlations among edaphic factors (pH and soil conductivity) and the relative abundance of specific phyla were most pronounced along local environmental gradients in the Lake Fryxell basin where Acidobacteria, Bacteroidetes, and Proteobacteria declined while Deinococcus\–Thermus and Gemmatimonadetes increased with soil conductivity (all P \< 0.1). Species richness was most strongly related to the soil conductivity gradient present within this study system. We suggest that the relative importance of pH versus soil conductivity in structuring microbial communities is related to the length of edaphic gradients and the spatial scale of sampling. These results highlight the importance of conducting studies over large ranges of key environmental gradients and across multiple spatial scales to assess the influence of environmental heterogeneity on the composition and diversity of microbial communities.

}, keywords = {LTER-MCM}, doi = {10.3389/fmicb.2018.01928}, url = {https://www.frontiersin.org/article/10.3389/fmicb.2018.01928/full}, author = {Feeser, Kelli L. and David J. Van Horn and Heather N. Buelow and Colman, Daniel R. and McHugh, Theresa A. and Okie, Jordan G. and Schwartz, Egbert and Cristina D. Takacs-Vesbach} } @inbook {4100, title = {The Climate of Snow and Ice as Boundary Condition for Microbial Life in Psychrophiles: From Biodiversity to Biotechnology}, year = {2017}, publisher = {Springer}, organization = {Springer}, edition = {2}, abstract = {

The microclimate and structure of snow and ice are a boundary condition as well as a matrix for a large spectrum of microbial life under alpine and polar conditions. Biological activity critically depends on the supply of energy, water and nutrients, with solar radiation as the prime source of energy, varying with latitude and altitude. The energy balance at the snow or ice surface provides the boundary condition for the fluxes of energy and water to the snow and ice, with important latitudinal differences from the temperate to the polar regions. The extreme situations of sunlit rocks surrounded by snow and the environment of Antarctic cryoconite holes, where ice, water, solar radiation and nutrients interact in particular ways, closes this review on ice and its effect on microbial life.

}, keywords = {LTER-MCM}, isbn = {978-3-319-57056-3}, doi = {10.1007/978-3-319-57057-010.1007/978-3-319-57057-0_1}, url = {http://link.springer.com/content/pdf/10.1007/978-3-319-57057-0}, author = {Kuhn, Michael and Andrew G Fountain}, editor = {R. Margesin} } @article {4112, title = {A communal catalogue reveals Earth{\textquoteright}s multiscale microbial diversity}, journal = {Nature}, volume = {551}, year = {2017}, month = {11/2017}, chapter = {457}, abstract = {

Our growing awareness of the microbial world\’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth\’s microbial diversity.

}, keywords = {LTER-MCM}, doi = {10.1038/nature24621}, url = {https://www.nature.com/articles/nature24621}, author = {Thompson, Luke R. and Sanders, Jon G. and McDonald, Daniel and Amir, Amnon and Ladau, Joshua and Locey, Kenneth J. and Prill, Robert J. and Tripathi, Anupriya and Gibbons, Sean M. and Ackermann, Gail and Navas-Molina, Jose A. and Janssen, Stefan and Kopylova, Evguenia and V{\'a}zquez-Baeza, Yoshiki and Antonio Gonz{\'a}lez and Morton, James T. and Mirarab, Siavash and Zech Xu, Zhenjiang and Jiang, Lingjing and Haroon, Mohamed F. and Kanbar, Jad and Zhu, Qiyun and Jin Song, Se and Kosciolek, Tomasz and Bokulich, Nicholas A. and Lefler, Joshua and Brislawn, Colin J. and Humphrey, Gregory and Owens, Sarah M. and Hampton-Marcell, Jarrad and Berg-Lyons, Donna and McKenzie, Valerie and Noah Fierer and Fuhrman, Jed A. and Clauset, Aaron and Stevens, Rick L. and Shade, Ashley and Pollard, Katherine S. and Goodwin, Kelly D. and Jansson, Janet K. and Gilbert, Jack A. and Knight, Rob and The Earth Microbiome Project Consortium} } @article {4022, title = {Decadal ecosystem response to an anomalous melt season in a polar desert in Antarctica}, journal = {Nature Ecology \& Evolution}, volume = {1}, year = {2017}, month = {09/2017}, pages = {1334-1338}, keywords = {LTER-MCM}, doi = {10.1038/s41559-017-0253-0}, url = {https://www.nature.com/articles/s41559-017-0253-0}, author = {Michael N. Gooseff and John E. Barrett and Byron Adams and Peter T. Doran and Andrew G Fountain and W. Berry Lyons and Diane M. McKnight and John C. Priscu and Eric R. Sokol and Cristina D. Takacs-Vesbach and Martijn L. Vandegehuchte and Ross A. Virginia and Diana H. Wall} } @article {4019, title = {Diversity and Distribution of Freshwater Aerobic Anoxygenic Phototrophic Bacteria across a Wide Latitudinal Gradient}, journal = {Frontiers in Microbiology}, volume = {8}, year = {2017}, month = {02/2017}, abstract = {

Aerobic anoxygenic phototrophs (AAPs) have been shown to exist in numerous marine and brackish environments where they are hypothesized to play important ecological roles. Despite their potential significance, the study of freshwater AAPs is in its infancy and limited to local investigations. Here, we explore the occurrence, diversity and distribution of AAPs in lakes covering a wide latitudinal gradient: Mongolian and German lakes located in temperate regions of Eurasia, tropical Great East African lakes, and polar permanently ice-covered Antarctic lakes. Our results show a widespread distribution of AAPs in lakes with contrasting environmental conditions and confirm that this group is composed of different members of the Alpha- and Betaproteobacteria. While latitude does not seem to strongly influence AAP abundance, clear patterns of community structure and composition along geographic regions were observed as indicated by a strong macro-geographical signal in the taxonomical composition of AAPs. Overall, our results suggest that the distribution patterns of freshwater AAPs are likely driven by a combination of small-scale environmental conditions (specific of each lake and region) and large-scale geographic factors (climatic regions across a latitudinal gradient).

}, keywords = {LTER-MCM}, doi = {10.3389/fmicb.2017.00175}, url = {http://journal.frontiersin.org/article/10.3389/fmicb.2017.00175/full}, author = {Ferrera, Isabel and Sarmento, Hugo and John C. Priscu and Amy Chiuchiolo and Jos{\'e} M. Gonz{\'a}lez and Grossart, Hans-Peter} } @article {4101, title = {High-resolution elevation mapping of the McMurdo Dry Valleys, Antarctica, and surrounding regions}, journal = {Earth System Science Data}, volume = {9}, year = {2017}, month = {07/2017}, pages = {435 - 443}, abstract = {

We present detailed surface elevation measurements for the McMurdo Dry Valleys, Antarctica derived from aerial lidar surveys flown in the austral summer of 2014\–2015 as part of an effort to understand geomorphic changes over the past decade. Lidar return density varied from 2 to \> 10 returns m\−2\ with an average of about 5 returns m\−2. Vertical and horizontal accuracies are estimated to be 7 and 3 cm, respectively. In addition to our intended targets, other ad hoc regions were also surveyed including the Pegasus flight facility and two regions on Ross Island, McMurdo Station, Scott Base (and surroundings), and the coastal margin between Cape Royds and Cape Evans. These data are included in this report and data release. The combined data are freely available at\ https://doi.org/10.5069/G9D50JX3.

}, keywords = {LTER-MCM}, doi = {10.5194/essd-9-435-2017}, url = {https://www.earth-syst-sci-data.net/9/435/2017/essd-9-435-2017.pdf}, author = {Andrew G Fountain and Fernandez-Diaz, Juan C. and Maciek K. Obryk and Joseph S. Levy and Michael N. Gooseff and David J. Van Horn and Morin, P and Shrestha, Ramesh} } @article {4032, title = {Impacts of permafrost degradation on a stream in Taylor Valley, Antarctica}, journal = {Geomorphology}, volume = {285}, year = {2017}, month = {05/2017}, pages = {205 - 213}, abstract = {

The McMurdo Dry Valleys (MDV) of Antarctica are an ice-free landscape that supports a complex, microbially dominated ecosystem despite a severely arid, cold environment (b 5 cm water equivalent/y, \− 18 \°C mean annual air temperature). Recent observations of permafrost degradation in the coastal zones of the MDV suggest that this region is nearing a threshold of rapid landscape change. In 2012, substantial thermokarst development was observed along several kilometers of the west branch of Crescent Stream in Taylor Valley mostly in the form of bank failures, whereas the adjacent east branch was unaffected. The objective of this study was to quantify the changes to the stream banks of the west branch of Crescent Stream and to determine the impacts on the composition of the stream bed material. Three annually repeated terrestrial LiDAR scans were compared to determine the rates of ground surface change caused by thermokarst formation on the stream bank. The areal extent of the thermokarst was shown to be decreasing; however, the average vertical rate of retreat remained constant. Field measurements of bed materials indicated that the west branch and the reach downstream of the confluence (of east and west branches) consistently contained more fines than the unaffected east branch. This suggests that the finer bed material is a result of the thermokarst development on the west branch. These finer bed material compositions are likely to increase the mobility of the bed material, which will have implications for stream morphology, stream algal mat communities, and downstream aquatic ecosystems.

}, keywords = {LTER-MCM}, doi = {10.1016/j.geomorph.2017.02.009}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0169555X16308467}, author = {Sudman, Zachary and Michael N. Gooseff and Andrew G Fountain and Joseph S. Levy and Maciek K. Obryk and David J. Van Horn} } @article {4020, title = {Glaciers in equilibrium, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {62}, year = {2016}, month = {07/2016}, pages = {976 - 989}, abstract = {

The McMurdo Dry Valleys are a cold, dry polar desert and the alpine glaciers therein exhibit small annual and seasonal mass balances, often \<\±0.06 m w.e. Typically, winter is the accumulation season, but significant snow storms can occur any time of year occasionally making summer the accumulation season. The yearly equilibrium line altitude is poorly correlated with mass balance because the elevation gradient of mass balance on each glacier can change dramatically from year to year. Most likely, winds redistribute the light snowfall disrupting the normal gradient of increasing mass balance with elevation. Reconstructed cumulative mass balance shows that the glaciers have lost \<2 m w.e. over the past half century and area changes show minimal retreat. In most cases these changes are less than the uncertainty and the glaciers are considered in equilibrium. Since 2000, however, the glaciers have lost mass despite relatively stable summer air temperatures suggesting a different mechanism in play. Whether this trend is a harbinger of future changes or a temporary excursion is unclear.

}, keywords = {LTER-MCM, Antarctica, glaciers, mass balance}, issn = {0022-1430}, doi = {10.1017/jog.2016.86}, url = {https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000861}, author = {Andrew G Fountain and Hassan J. Basagic and Niebuhr, Spencer} } @article {4102, title = {The Impact of a Large-Scale Climate Event on Antarctic Ecosystem Processes}, journal = {BioScience}, volume = {66}, year = {2016}, month = {10/2016}, pages = {848 - 863}, abstract = {

Extreme climate and weather events, such as a drought, hurricanes, or ice storms, can strongly imprint ecosystem processing and may alter ecosystem structure. Ecosystems in extreme environments are particularly vulnerable because of their adaptation to severe limitations in energy, water, or nutrients. The vulnerability can be expressed as a relatively long-lasting ecosystem response to a small or brief change in environmental conditions. Such an event occurred in Antarctica and affected two vastly different ecosystems: a marine-dominated coastal system and a terrestrial polar desert. Both sites experienced winds that warmed air temperatures above the 0\°C threshold, resulting in extensive snow and ice melt and triggering a series of cascading effects through the ecosystems that are continuing to play out more than a decade later. This highlights the sensitivity of Antarctic ecosystems to warming events, which should occur more frequently in the future with global climate warming.

}, keywords = {LTER-MCM}, issn = {0006-3568}, doi = {10.1093/biosci/biw110}, url = {http://academic.oup.com/bioscience/article-pdf/66/10/848/7510601/biw110.pdf}, author = {Andrew G Fountain and Saba, Grace and Byron Adams and Peter T. Doran and Fraser, William and Michael N. Gooseff and Maciek K. Obryk and John C. Priscu and Sharon E. Stammerjohn and Ross A. Virginia} } @article {4030, title = {Responses of Antarctic Marine and Freshwater Ecosystems to Changing Ice Conditions}, journal = {BioScience}, volume = {66}, year = {2016}, month = {Jan-10-2016}, pages = {864 - 879}, keywords = {LTER-MCM}, issn = {0006-3568}, doi = {10.1093/biosci/biw109}, url = {https://academic.oup.com/bioscience/article-lookup/doi/10.1093/biosci/biw109https://academic.oup.com/bioscience/article/66/10/864/2415532/Responses-of-Antarctic-Marine-and-Freshwater}, author = {Maciek K. Obryk and Peter T. Doran and Friedlaender, Ari S. and Michael N. Gooseff and Li, Wei and Rachael M. Morgan-Kiss and John C. Priscu and Schofield, Oscar and Sharon E. Stammerjohn and Steinberg, Deborah K. and Hugh W. Ducklow} } @article {3012, title = {Deep groundwater and potential subsurface habitats beneath an Antarctic dry valley}, journal = {Nature Communications}, volume = {6}, year = {2015}, month = {Apr-04-2017}, pages = {6831}, abstract = {The occurrence of groundwater in Antarctica, particularly in the ice-free regions and along the coastal margins is poorly understood. Here we use an airborne transient electromagnetic (AEM) sensor to produce extensive imagery of resistivity beneath Taylor Valley. Regional-scale zones of low subsurface resistivity were detected that are inconsistent with the high resistivity of glacier ice or dry permafrost in this region. We interpret these results as an indication that liquid, with sufficiently high solute content, exists at temperatures well below freezing and considered within the range suitable for microbial life. These inferred brines are widespread within permafrost and extend below glaciers and lakes. One system emanates from below Taylor Glacier into Lake Bonney and a second system connects the ocean with the eastern 18 km of the valley. A connection between these two basins was not detected to the depth limitation of the AEM survey (~350 m).}, keywords = {LTER-MCM}, doi = {10.1038/ncomms7831}, url = {http://www.nature.com/doifinder/10.1038/ncomms7831}, author = {Jill A. Mikucki and Auken, E. and Tulaczyk, S and Ross A. Virginia and Schamper, C. and S{\o}rensen, K. I. and Peter T. Doran and Hilary A. Dugan and Foley, N.} } @article {3210, title = {Experimental formation of pore fluids in McMurdo Dry Valleys soils}, journal = {Antarctic Science}, volume = {27}, year = {2015}, month = {04/2015}, pages = {163 - 171}, abstract = {

The aim of the study was to determine if soil salt deliquescence and brine hydration can occur under laboratory conditions using natural McMurdo Dry Valleys soils. The experiment was a laboratory analogue for the formation of isolated patches of hypersaline, damp soil, referred to as \‘wet patches\’. Soils were oven dried and then hydrated in one of two humidity chambers: one at 100\% relative humidity and the second at 75\% relative humidity. Soil hydration is highly variable, and over the course of 20 days of hydration, ranged from increases in water content by mass from 0\–16\% for 122 soil samples from Taylor Valley. The rate and absolute amount of soil hydration correlates well with the soluble salt content of the soils but not with grain size distribution. This suggests that the formation of bulk pore waters in these soils is a consequence of salt deliquescence and hydration of the brine from atmospheric water vapour.

}, keywords = {LTER-MCM}, issn = {0954-1020}, doi = {10.1017/S0954102014000479}, url = {http://www.journals.cambridge.org/abstract_S0954102014000479}, author = {Joseph S. Levy and Andrew G Fountain and W. Berry Lyons and Kathleen A. Welch} } @article {3715, title = {Global environmental change and the nature of aboveground net primary productivity responses: insights from long-term experiments}, journal = {Oecologia}, volume = {177}, year = {2015}, month = {04/2015}, pages = {935 - 947}, keywords = {LTER-MCM}, issn = {0029-8549}, doi = {10.1007/s00442-015-3230-9}, url = {http://link.springer.com/10.1007/s00442-015-3230-9http://link.springer.com/content/pdf/10.1007/s00442-015-3230-9}, author = {Smith, Melinda D. and La Pierre, Kimberly J. and Collins, SL and Knapp, Alan K. and Gross, Katherine L. and John E. Barrett and Frey, Serita D. and Gough, Laura and Miller, Robert J. and Morris, James T. and Rustad, Lindsey E. and Yarie, John} } @article {3205, title = {Patterns and processes of salt efflorescences in the McMurdo region, Antarctica}, journal = {Artic, Antarctic and Alpine Research}, year = {2015}, abstract = {

Evaporite salts are abundant around the McMurdo region, Antarctica (~78\°S) due to very low precipitation, low relative humidity, and limited overland flow. Hygroscopic salts in the McMurdo Dry Valleys (MDVs) are preferentially formed in locations where liquid water is present in the austral summer, including along ephemeral streams, ice-covered lake boundaries, or shallow groundwater tracks. In this study, we collected salts from the Miers, Garwood, and Taylor Valleys on the Antarctic continent, as well as around McMurdo Station on Ross Island in close proximity to water sources with the goal of understanding salt geochemistry in relationship to the hydrology of the area. Halite is ubiquitous; sodium is the major cation (ranging from 70\%\–90\% of cations by meq kg\−1\ sediment) and chloride is the major anion (\>50\%) in nearly all samples. However, a wide variety of salt phases and morphologies are tentatively identified through scanning electron microscopy (SEM) and X-ray diffraction (XRD) work. We present new data that identifies trona (Na3(CO3)(HCO3)\·2H2O), tentative gaylussite (Na2Ca(CO3)2\·5H2O), and tentative glauberite (Na2Ca(SO4)2) in the MDV, of which the later one has not been documented previously. Our work allows for the evaluation of processes that influence brine evolution on a local scale, consequently informing assumptions underlying large-scale processes (such as paleoclimate) in the MDV. Hydrological modeling conducted in FREZCHEM and PHREEQC suggests that a model based on aerosol deposition alone in low elevations on the valley floor inadequately characterizes salt distributions found on the surfaces of the soil because it does not account for other hydrologic inputs/outputs. Implications for the salt distributions include their use as tracers for paleolake levels, geochemical tracers of ephemeral water tracks or \“wet patches\” in the soil, indicators of chemical weathering products, and potential delineators of ecological communities.

}, keywords = {LTER-MCM}, url = {http://aaarjournal.org/doi/abs/10.1657/AAAR0014-024}, author = {Bisson, K. M. and Kathleen A. Welch and Sue Welch and Sheets, J. M. and W. Berry Lyons and Joseph S. Levy and Andrew G Fountain} } @article {3222, title = {A roadmap for Antarctic and Southern Ocean science for the next two decades and beyond}, journal = {Antarctic Science}, volume = {27}, year = {2015}, month = {Jan-02-2015}, pages = {3 - 18}, abstract = {

Antarctic and Southern Ocean science is vital to understanding natural variability, the processes that govern global change and the role of humans in the Earth and climate system. The potential for new knowledge to be gained from future Antarctic science is substantial. Therefore, the international Antarctic community came together to \‘scan the horizon\’ to identify the highest priority scientific questions that researchers should aspire to answer in the next two decades and beyond. Wide consultation was a fundamental principle for the development of a collective, international view of the most important future directions in Antarctic science. From the many possibilities, the horizon scan identified 80 key scientific questions through structured debate, discussion, revision and voting. Questions were clustered into seven topics: i) Antarctic atmosphere and global connections, ii) Southern Ocean and sea ice in a warming world, iii) ice sheet and sea level, iv) the dynamic Earth, v) life on the precipice, vi) near-Earth space and beyond, and vii) human presence in Antarctica. Answering the questions identified by the horizon scan will require innovative experimental designs, novel applications of technology, invention of next-generation field and laboratory approaches, and expanded observing systems and networks. Unbiased, non-contaminating procedures will be required to retrieve the requisite air, biota, sediment, rock, ice and water samples. Sustained year-round access to Antarctica and the Southern Ocean will be essential to increase winter-time measurements. Improved models are needed that represent Antarctica and the Southern Ocean in the Earth System, and provide predictions at spatial and temporal resolutions useful for decision making. A co-ordinated portfolio of cross-disciplinary science, based on new models of international collaboration, will be essential as no scientist, programme or nation can realize these aspirations alone

}, keywords = {LTER-MCM}, issn = {0954-1020}, doi = {10.1017/S0954102014000674}, url = {http://www.journals.cambridge.org/abstract_S0954102014000674}, author = {Kennicutt, M.C. and Steven L. Chown and Cassano, J.J. and Liggett, D. and Lloyd S. Peck and Massom, R. and Rintoul, S.R. and Storey, J. and Vaughan, D.G. and Wilson, T.J. and Allison, I. and Ayton, J. and Badhe, R. and Baeseman, J. and Barrett, P.J. and Elanor R. Bell and Bertler, N. and Bo, S. and Brandt, A. and David Bromwich and Craig S Cary and Clark, M.S. and Peter Convey and Costa, E.S. and Cowan, D. and Deconto, R. and Dunbar, R. and Elfring, C. and Escutia, C. and Francis, J. and Fricker, H.A. and Fukuchi, M. and Gilbert, N. and Gutt, J. and Havermans, C. and Hik, D. and Hosie, G. and Jones, C. and Kim, Y.D. and Le Maho, Y. and Lee, S.H. and Leppe, M. and Leitchenkov, G. and Li, X. and Lipenkov, V. and Lochte, K. and L{\'o}pez-Mart{\'\i}nez, J. and {\"u}decke, C. and W. Berry Lyons and Marenssi, S. and Miller, H. and Morozova, P. and Naish, T. and Nayak, S. and Ravindra, R. and Retamales, J. and Ricci, C.A. and Rogan-Finnemore, M. and Ropert-Coudert, Y. and Samah, A.A. and Sanson, L. and Scambos, T. and I.R. Schloss and Shiraishi, K. and Siegert, M.J. and Sim{\~o}es, J.C. and Storey, B. and Sparrow, M.D. and Diana H. Wall and Walsh, J.C. and Wilson, G. and Winther, J.G. and J.C. Xavier and Yang, H. and Sutherland, W.J.} } @mastersthesis {3201, title = {Elemental Cycling in a Flow-Through Lake in the McMurdo Dry Valleys, Antarctica: Lake Miers}, volume = {Master Thesis}, year = {2014}, month = {06/2014}, pages = {122}, school = {Ohio State University}, type = {masters}, address = {Columbus}, abstract = {

The ice-free area in Antarctica known as the McMurdo Dry Valleys has been monitored biologically, meteorologically, hydrologically, and geochemically continuously since the onset of the MCM-LTER in 1993. This area contains a functioning ecosystem living in an extremely delicate environment. Only a few degrees of difference in air temperature can effect on the hydrologic system, making it a prime area to study ongoing climate change. The unique hydrology of Lake Miers, i.e. its flowthrough nature, makes it an ideal candidate to study the mass balance of a McMurdo Dry Valley lake because both input and output concentrations can be analyzed. This study seeks to understand the physical and geochemical hydrology of Lake Miers relative to other MCMDV lakes. Samples were collected from the two inflowing streams, the outflowing stream, and the lake itself at 11 depths to analyze a suite of major cations (Li+ , Na+ , K+ , Mg+ , Ca2+), major anions (Cl- , Br- , F- , SO4 2- , ΣCO2), nutrients (NO2 - , NO3 - , NH4 + , PO4 3- , Si), trace elements (Mo, Rb, Sr, Ba, U, V, Cu, As), water isotopes (δD, δ 18O), and dissolved organic carbon (DOC). The lake acts as a sink for all constituents analyzed, but by amounts varying from ~10\% (DOC, NH4 + , and NO2 - ) to PO4 3- at nearly 100\%, indicating this lake may be P-limited. Cl- , a typically conservative element, was only 79\% retained, which could be due to the late season sample collection, hyperheic zone influences, or other factors. The hyperheic zone\’s role in lake and stream iii geochemistry was analyzed with a 24-hour sampling event. The positive relationships between stream flow and solute concentrations indicate that the delta in Miers Valley plays a role in controlling stream geochemistry and future work could help to explain this relationship. Lake depth profiles of trace elements U, V, Cu, and As decrease relative to Cl in the deepest part of the lake, while non-reducing trace elements show increases with depth. SO4 2- and dissolved O2 lake depth profiles decrease from 53 μM and 22.3 mg/L to 18 μM and 1.8 mg/L, respectively, at depth, indicating that the lake bottom is under reducing and near anoxic conditions. Lake depth profiles show that, while the \“biological pump\” may be a factor controlling lake chemistry, it is masked by the stronger signal of diffusion from the lake bottom sediments and requires future work to understand fully. The \“age\” of Lake Miers was calculated with a diffusion model to be 84 years, which agrees with other estimates of 100-300 years. The diffusion of solutes from the lake bottom and the redox conditions at depth are two major processes controlling the geochemistry of Lake Miers, and future work can help determine their extent and relationship with other processes.

}, keywords = {LTER-MCM}, url = {https://etd.ohiolink.edu/!etd.send_file?accession=osu1413291502\&disposition=inline}, author = {Alexandria Corinne Fair and W. Berry Lyons}, editor = {Anne E. Carey and Yu-Ping Chin} } @article {3207, title = {Forum: Climate Change and Environmental History}, journal = {Environmental History}, volume = {19}, year = {2014}, month = {04/2014}, pages = {281 - 364}, abstract = {

This Forum explores global climate change, one of this century\&$\#$39;s most prominent environmental issues. Authors answer two critical questions: (1) How does the study of climate history enrich the field of environmental history more broadly? (2) How can environmental historians contribute to present-day understandings of and responses to global climate change? This introductory essay (and the Forum more generally) contribute to both environmental history research and climate change discussions by grappling with several key issues including the agency of nonhuman nature and environmental determinism, environmental governance, climate as a cultural construction, the history of environmental ideas and discourse, environmental narratives, the commodification of nature, and the politicization of the natural and life sciences. This essay also shows how the study of climate history provides methodological and practical tools for environmental historians. It analyzes the role of interdisciplinary sources and archives, scale, the place of science in environmental history scholarship, and the relevance of environmental histories for present-day policymaking and public discussions about climate change.

}, keywords = {LTER-MCM}, issn = {1084-5453}, doi = {10.1093/envhis/emu004}, url = {http://envhis.oxfordjournals.org/cgi/doi/10.1093/envhis/emu004}, author = {Carey, M. and Garone, P. and Howkins, Adrian and Endfield, G. H. and Culver, L. and White, S. and Johnson, S. and Fleming, J. R. and Garone, P.} } @article {3209, title = {Hyperspectral measurements of wet, dry and saline soils from the McMurdo Dry Valleys: soil moisture properties from remote sensing}, journal = {Antarctic Science}, volume = {26}, year = {2014}, month = {10/2014}, pages = {565 - 572}, abstract = {

Soil moisture is a spatially heterogeneous quantity in the McMurdo Dry Valleys of Antarctica that exerts a large influence on the biological community and on the thermal state of Dry Valleys permafrost. The goal of this project was to determine whether hyperspectral remote sensing techniques could be used to determine soil moisture conditions in the Dry Valleys. We measured the spectral reflectance factors of wetted soil samples from the Dry Valleys under natural light conditions and related diagnostic spectral features to surface layer soil moisture content. Diagnostic water absorption features in the spectra at 1.4 \µm and 1.9 \µm were present in all samples, including samples doped with high concentrations of chloride salts. The depth of the 1.4 \µm absorption is shown to increase linearly with increasing gravimetric water content. These results suggest that airborne hyperspectral imaging of the Dry Valleys could generate soil moisture maps of this environment over large spatial areas using non-invasive remote-sensing techniques.

}, keywords = {LTER-MCM}, issn = {0954-1020}, doi = {10.1017/S0954102013000977}, url = {http://www.journals.cambridge.org/abstract_S0954102013000977}, author = {Joseph S. Levy and Nolin, Anne and Andrew G Fountain and Head, James W.} } @article {3202, title = {The McMurdo Dry Valleys: A landscape on the threshold of change}, journal = {Geomorphology}, volume = {225}, year = {2014}, month = {11/2014}, pages = {25 - 35}, abstract = {

Field observations of coastal and lowland regions in the McMurdo Dry Valleys suggest they are on the threshold of rapid topographic change, in contrast to the high elevation upland landscape that represents some of the lowest rates of surface change on Earth. A number of landscapes have undergone dramatic and unprecedented landscape changes over the past decade including, the Wright Lower Glacier (Wright Valley) \— ablated several tens of meters, the Garwood River (Garwood Valley) has incised \>\ 3\ m into massive ice permafrost, smaller streams in Taylor Valley (Crescent, Lawson, and Lost Seal Streams) have experienced extensive down-cutting and/or bank undercutting, and Canada Glacier (Taylor Valley) has formed sheer, \>\ 4\ meter deep canyons. The commonality between all these landscape changes appears to be sediment on ice acting as a catalyst for melting, including ice-cement permafrost thaw. We attribute these changes to increasing solar radiation over the past decade despite no significant trend in summer air temperature. To infer possible future landscape changes in the McMurdo Dry Valleys, due to anticipated climate warming, we map \‘at risk\’ landscapes defined as those with buried massive ice in relative warm regions of the valleys. Results show that large regions of the valley bottoms are \‘at risk\’. Changes in surface topography will trigger important responses in hydrology, geochemistry, and biological community structure and function.

}, keywords = {LTER-MCM}, issn = {0169555X}, doi = {10.1016/j.geomorph.2014.03.044}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0169555X14001780http://api.elsevier.com/content/article/PII:S0169555X14001780?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S0169555X14001780?httpAccept=text/plain}, author = {Andrew G Fountain and Joseph S. Levy and Michael N. Gooseff and David J. Van Horn} } @article {1068, title = {Near-Surface Internal Melting - a Substantial Mass Loss on Antarctic Dry Valley Glaciers.}, journal = {Journal of Glaciology}, volume = {60}, year = {2014}, month = {04/2014}, pages = {361-374}, chapter = {361}, abstract = {The McMurdo Dry Valleys, southern Victoria Land, East Antarctica, are a polar desert, and melt from glacial ice is the primary source of water to streams, lakes and associated ecosystems. Previous work found that to adequately model glacier ablation and subsurface ice temperatures with a surface energy-balance model required including the transmission of solar radiation into the ice. Here we investigate the contribution of subsurface melt to the mass balance of (and runoff from) Dry Valley glaciers by including a drainage process in the model and applying the model to three glacier sites using 13years of hourly meteorological data. Model results for the smooth glacier surfaces common to many glaciers in the Dry Valleys showed that sublimation was typically the largest component of surface lowering, with rare episodes of surface melting, consistent with anecdotal field observations. Results also showed extensive internal melting 5-15 cm below the ice surface, the drainage of which accounted for 50\% of summer ablation. This is consistent with field observations of subsurface streams and formation of a weathering crust. We identify an annual cycle of weathering crust formation in summer and its removal during the 10 months of winter sublimation.}, keywords = {LTER-MCM}, doi = {10.3189/2014JoG13J095}, author = {Hoffman, M and Andrew G Fountain and Liston, G} } @article {3219, title = {The spatial structure of Antarctic biodiversity}, journal = {Ecological Monographs}, volume = {84}, year = {2014}, month = {05/2014}, pages = {203 - 244}, abstract = {

Patterns of environmental spatial structure lie at the heart of the most fundamental and familiar patterns of diversity on Earth. Antarctica contains some of the strongest environmental gradients on the planet and therefore provides an ideal study ground to test hypotheses on the relevance of environmental variability for biodiversity. To answer the pivotal question, \“How does spatial variation in physical and biological environmental properties across the Antarctic drive biodiversity?\” we have synthesized current knowledge on environmental variability across terrestrial, freshwater, and marine Antarctic biomes and related this to the observed biotic patterns. The most important physical driver of Antarctic terrestrial communities is the availability of liquid water, itself driven by solar irradiance intensity. Patterns of biota distribution are further strongly influenced by the historical development of any given location or region, and by geographical barriers. In freshwater ecosystems, free water is also crucial, with further important influences from salinity, nutrient availability, oxygenation, and characteristics of ice cover and extent. In the marine biome there does not appear to be one major driving force, with the exception of the oceanographic boundary of the Polar Front. At smaller spatial scales, ice cover, ice scour, and salinity gradients are clearly important determinants of diversity at habitat and community level. Stochastic and extreme events remain an important driving force in all environments, particularly in the context of local extinction and colonization or recolonization, as well as that of temporal environmental variability. Our synthesis demonstrates that the Antarctic continent and surrounding oceans provide an ideal study ground to develop new biogeographical models, including life history and physiological traits, and to address questions regarding biological responses to environmental variability and change.

}, keywords = {LTER-MCM}, issn = {0012-9615}, doi = {10.1890/12-2216.1}, url = {http://www.esajournals.org/doi/abs/10.1890/12-2216.1}, author = {Peter Convey and Steven L. Chown and Clarke, Andrew and Barnes, David K. A. and Bokhorst, Stef and Vonda Cummings and Hugh W. Ducklow and Francesco Frati and Green, T. G. Allan and Shulamit Gordon and Griffiths, Huw J. and Clive Howard-Williams and Huiskes, Ad H. L. and Johanna Laybourn-Parry and W. Berry Lyons and McMinn, Andrew and Morley, Simon A. and Lloyd S. Peck and Quesada, Antonio and Robinson, Sharon A. and Schiaparelli, Stefano and Diana H. Wall} } @article {3206, title = {Spring thaw ionic pulses boost nutrient availability and microbial growth in entombed Antarctic Dry Valley cryoconite holes}, journal = {Frontiers in Microbiology}, volume = {5}, year = {2014}, month = {12/2014}, abstract = {

The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0\°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of spring thaw toward fully melted holes. The cryoconite holes had a mean isolation age from the glacial drainage system of 3.4 years, with an increasing mass of aqueous nutrients (dissolved organic carbon, total nitrogen, total phosphorus) with longer isolation age. During the initial melt there was a mean nine times enrichment in dissolved chloride relative to mean concentrations of the initial frozen holes indicative of an ionic pulse, with similar mean nine times enrichments in nitrite, ammonium, and dissolved organic matter. Nitrate was enriched twelve times and dissolved organic nitrogen six times, suggesting net nitrification, while lower enrichments for dissolved organic phosphorus and phosphate were consistent with net microbial phosphorus uptake. Rates of bacterial production were significantly elevated during the ionic pulse, likely due to the increased nutrient availability. There was no concomitant increase in photosynthesis rates, with a net depletion of dissolved inorganic carbon suggesting inorganic carbon limitation. Potential nitrogen fixation was detected in fully melted holes where it could be an important source of nitrogen to support microbial growth, but not during the ionic pulse where nitrogen availability was higher. This study demonstrates that ionic pulses significantly alter the timing and magnitude of microbial activity within entombed cryoconite holes, and adds credence to hypotheses that ionic enrichments during freeze-thaw can elevate rates of microbial growth and activity in other icy habitats, such as ice veins and subglacial regelation zones

}, keywords = {LTER-MCM}, doi = {10.3389/fmicb.2014.00694}, url = {http://journal.frontiersin.org/article/10.3389/fmicb.2014.00694/abstract}, author = {Telling, J. and Alexandre M. Anesio and Martyn Tranter and Andrew G Fountain and Thomas H. Nylen and Hawkings, Jon and Singh, Virendra B. and Kaur, Preeti and Musilova, Michaela and Wadham, J. L.} } @article {1091, title = {Accelerated thermokarst formation in the McMurdo Dry Valleys, Antarctica}, journal = {Scientific Reports}, volume = {3}, year = {2013}, month = {07/2013}, keywords = {LTER-MCM}, doi = {10.1038/srep02269}, url = {http://www.nature.com/srep/2013/130724/srep02269/full/srep02269.html?WT.ec_id=SREP-20130730}, author = {Joseph S. Levy and Andrew G Fountain and Dickson, James L. and Head, James W. and Okal, Marianne and Marchant, David R. and Watters, Jaclyn} } @article {3211, title = {Carbon Sequestration and Release from Antarctic Lakes: Lake Vida and West Lake Bonney (McMurdo Dry Valleys)}, journal = {Aquatic Geochemistry}, volume = {19}, year = {2013}, month = {03/2013}, pages = {135 - 145}, abstract = {

Perennial ice covers on many Antarctic lakes have resulted in high lake inorganic carbon contents. The objective of this paper was to evaluate and compare the brine and CO2\ chemistries of Lake Vida (Victoria Valley) and West Lake Bonney (Taylor Valley), two lakes of the McMurdo Dry Valleys (East Antarctica), and their potential consequences during global warming. An existing geochemical model (FREZCHEM-15) was used to convert measured molarity into molality needed for the FREZCHEM model, and this model added a new algorithm that converts measured DIC into carbonate alkalinity needed for the FREZCHEM model. While quite extensive geochemical information exists for ice-covered Taylor Valley lakes, such as West Lake Bonney, only limited information exists for the recently sampled brine of \>25\ m ice-thick Lake Vida. Lake Vida brine had a model-calculated pCO2\ =\ 0.60 bars at the field pH (6.20); West Lake Bonney had a model-calculated pCO2\ =\ 5.23\ bars at the field pH (5.46). Despite the high degree of atmospheric CO2supersaturation in West Lake Bonney, it remains significantly undersaturated with the gas hydrate, CO2\·6H2O, unless these gas hydrates are deep in the sediment layer or are metastable having formed under colder temperatures or greater pressures. Because of lower temperatures, Lake Vida could start forming CO2\·6H2O at lower pCO2\ values than West Lake Bonney; but both lakes are significantly undersaturated with the gas hydrate, CO2\·6H2O. For both lakes, simulation of global warming from current subzero temperatures (\−13.4\ \°C in Lake Vida and \−4.7\ \°C in West Lake Bonney) to 10\ \°C has shown that a major loss of solution-phase carbon as CO2\ gases and carbonate minerals occurred when the temperatures rose above 0\ \°C and perennial ice covers would disappear. How important these Antarctic CO2\ sources will be for future global warming remains to be seen. But a recent paper has shown that methane increased in atmospheric concentration due to deglaciation about 10,000\ years ago. So, CO2\ release from ice lakes might contribute to atmospheric gases in the future.

}, keywords = {LTER-MCM}, issn = {1380-6165}, doi = {10.1007/s10498-012-9184-1}, url = {http://link.springer.com/10.1007/s10498-012-9184-1http://link.springer.com/content/pdf/10.1007/s10498-012-9184-1}, author = {G. M. Marion and A. E. Murray and Wagner, Bernd and Christian H. Fritsen and Kenig, Fabien and Peter T. Doran} } @article {1077, title = {Characterization of fulvic acid fractions of dissolved organic matter during ice-out in a hyper-eutrophic, coastal pond in Antarctica}, journal = {Environmental Research Letters}, volume = {8}, year = {2013}, month = {12/2013}, pages = {045015}, abstract = {Dissolved humic material (HDOM) is ubiquitous to all natural waters and its source material influences its chemical structure, reactivity, and bioavailability. While terrestrially derived HDOM reference materials distributed by the International Humic Substances Society (IHSS) have been readily available to engineering and scientific communities, a microbially derived reference HDOM was not, despite the well-characterized differences in the chemistry and reactivity of HDOM derived from terrestrial versus microbial sources. To address this gap, we collected a microbial reference fulvic acid from Pony Lake (PLFA) for distribution through the IHSS. Pony Lake is a saline coastal pond on Ross Island, Antarctica, where the landscape is devoid of terrestrial plants. Sample collection occurred over a 17-day period in the summer season at Pony Lake. During this time, the dissolved organic carbon (DOC) concentrations increased nearly two-fold, and the fulvic acid fraction (collected using the XAD-8 method) accounted for 14.6\% of the DOC. During the re-concentration and desalting procedures we isolated two other chemically distinct fulvic acid fractions: (1) PLFA-2, which was high in carbohydrates and (2) PLFA-CER, which was high in nitrogen. The chemical characteristics (elemental analysis, optical characterization with UV{\textendash}vis and fluorescence spectroscopy, and 13C NMR spectroscopy) of the three fulvic acid fractions helped to explain their behavior during isolation.}, keywords = {LTER-MCM}, doi = {10.1088/1748-9326/8/4/045015}, author = {Kaelin M. Cawley and Diane M. McKnight and Penney L. Miller and Rose M. Cory and Fimmen, Ryan L and Guerard, Jennifer and Markus Dieser and Chris Jaros and Yu-Ping Chin and Christine M. Foreman} } @article {1078, title = {Characterization of IHSS Pony Lake fulvic acid dissolved organic matter by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry and fluorescence spectroscopy}, journal = {Organic Geochemistry}, volume = {65}, year = {2013}, month = {12/2013}, pages = {19 - 28}, keywords = {LTER-MCM}, doi = {10.1016/j.orggeochem.2013.09.013}, url = {http://www.sciencedirect.com/science/article/pii/S0146638013002167}, author = {D{\textquoteright}Andrilli, Juliana and Christine M. Foreman and Marshall, Alan G. and Diane M. McKnight} } @article {1082, title = {Do Cryoconite Holes have the Potential to be Significant Sources of C, N, and P to Downstream Depauperate Ecosystems of Taylor Valley, Antarctica?}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {45}, year = {2013}, month = {11/2013}, pages = {440 - 454}, keywords = {LTER-MCM}, doi = {10.1657/1938-4246-45.4.440}, author = {Bagshaw, Elizabeth and Martyn Tranter and Andrew G Fountain and Kathleen A. Welch and Hassan J. Basagic and W. Berry Lyons} } @article {1079, title = {Environmental factors influencing diatom communities in Antarctic cryoconite holes}, journal = {Environmental Research Letters}, volume = {8}, year = {2013}, month = {12/2013}, pages = {045006}, keywords = {LTER-MCM}, doi = {10.1088/1748-9326/8/4/045006}, url = {http://iopscience.iop.org/1748-9326/8/4/045006/pdf/1748-9326_8_4_045006.pdf}, author = {Lee F. Stanish and Bagshaw, Elizabeth and Diane M. McKnight and Andrew G Fountain and Martyn Tranter} } @article {1086, title = {Garwood Valley, Antarctica: A new record of Last Glacial Maximum to Holocene glaciofluvial processes in the McMurdo Dry Valleys}, journal = {Geological Society of America Bulletin}, volume = {125}, year = {2013}, month = {09/2013}, pages = {1484 - 1502}, keywords = {LTER-MCM}, doi = {10.1130/B30783.1}, url = {http://bulletin.geoscienceworld.org/content/early/2013/06/07/B30783.1.abstract}, author = {Joseph S. Levy and Andrew G Fountain and O{\textquoteright}Connor, J. E. and Kathleen A. Welch and W. Berry Lyons} } @article {1088, title = {Microbial growth under humic-free conditions in a supraglacial stream system on the Cotton Glacier, Antarctica}, journal = {Environmental Research Letters}, volume = {8}, year = {2013}, month = {09/2013}, pages = {035022}, abstract = {During the austral summers of 2004 and 2009, we sampled a supraglacial stream on the Cotton Glacier, Antarctica. The stream dissolved organic matter (DOM) was low (44{\textendash}48 μM C) and lacked detectable humic fluorescence signatures. Analysis of the excitation emissions matrices (EEMs) indicated that amino-acid fluorophores dominated, consistent with DOM of microbial origin, with little humic-like fluorescence. In most aquatic ecosystems, humic DOM attenuates harmful UV radiation and its absence may represent an additional stressor influencing the microbial community. Nonetheless, the stream contained an active microbial assemblage with bacterial cell abundances from 2.94 {\texttimes} 104 to 4.97 {\texttimes} 105 cells ml-1, and bacterial production ranging from 58.8 to 293.2 ng C l-1 d-1. Chlorophyll-a concentrations ranged from 0.3 to 0.53 μg l-1 indicating that algal phototrophs were the probable source of the DOM. Microbial isolates produced a rainbow of pigment colors, suggesting adaptation to stress, and were similar to those from other cryogenic systems (Proteobacteria and Bacteroidetes lineages). Supraglacial streams provide an example of contemporary microbial processes on the glacier surface and a natural laboratory for studying microbial adaptation to the absence of humics.}, keywords = {LTER-MCM}, doi = {10.1088/1748-9326/8/3/035022}, url = {http://iopscience.iop.org/1748-9326/8/3/035022}, author = {Christine M. Foreman and Rose M. Cory and Morris, Cindy E and Michael D. SanClements and Smith, Heidi J and John T. Lisle and Penney L. Miller and Yu-Ping Chin and Diane M. McKnight} } @article {1081, title = {Physicochemical and biological dynamics in a coastal Antarctic lake as it transitions from frozen to open water}, journal = {Antarctic Science}, volume = {25}, year = {2013}, month = {12/2013}, pages = {663{\textendash}675}, keywords = {LTER-MCM}, author = {Markus Dieser and Christine M. Foreman and Chris Jaros and John T. Lisle and Mark C. Greenwood and Johanna Laybourn-Parry and Penney L. Miller and Yu-Ping Chin and Diane M. McKnight} } @article {1100, title = {Water track modification of soil ecosystems in the Lake Hoare basin, Taylor Valley, Antarctica}, journal = {Antarctic Science}, year = {2013}, pages = {1 - 10}, keywords = {LTER-MCM}, doi = {10.1017/S095410201300045X}, author = {Joseph S. Levy and Andrew G Fountain and Michael N. Gooseff and John E. Barrett and Robert Vantreese and Kathleen A. Welch and W. Berry Lyons and Uffe N. Nielsen and Diana H. Wall} } @article {1101, title = {Aeolian flux of biotic and abiotic material in Taylor Valley, Antarctica}, journal = {Geomorphology}, volume = {155-156}, year = {2012}, month = {6/2012}, pages = {102 - 111}, keywords = {LTER-MCM}, doi = {10.1016/j.geomorph.2011.12.009}, url = {http://www.sciencedirect.com/science/article/pii/S0169555X11006222}, author = {Marie {\v S}aback{\'a} and John C. Priscu and Hassan J. Basagic and Andrew G Fountain and Diana H. Wall and Ross A. Virginia and Mark C. Greenwood} } @article {3535, title = {Challenges to the Future Conservation of the Antarctic}, journal = {Science}, volume = {337}, year = {2012}, month = {Jan-07-2013}, pages = {158 - 159}, abstract = {

The Antarctic Treaty System, acknowledged as a successful model of cooperative regulation of one of the globe\&$\#$39;s largest commons (1), is under substantial pressure. Concerns have been raised about increased stress on Antarctic systems from global environmental change and growing interest in the region\&$\#$39;s resources (2,\ 3). Although policy-makers may recognize these challenges, failure to respond in a timely way can have substantial negative consequences. We provide a horizon scan, a systematic means for identifying emerging trends and assisting decision-makers in identifying policies that address future challenges (2,\ 3). Previous analyses of conservation threats in the Antarctic have been restricted to matters for which available evidence is compelling (4). We reconsider these concerns because they might escalate quickly, judging from recent rapid environmental change in parts of Antarctica and increasing human interest in the region (see the map). We then focus on a more distant time horizon.

}, keywords = {LTER-MCM}, issn = {0036-8075}, doi = {10.1126/science.1222821}, url = {http://www.sciencemag.org/cgi/doi/10.1126/science.1222821}, author = {Steven L. Chown and Lee, J. E. and Hughes, K. A. and Barnes, J. and Barrett, P.J. and D.M. Bergstrom and Convey, P. and Cowan, Don A. and Crosbie, K. and Dyer, G. and Frenot, Y. and Grant, S. M. and Herr, D. and Kennicutt, M. C. and Lamers, M. and Murray, A. and Possingham, H. P. and Reid, K. and Riddle, M. J. and Ryan, P. G. and Sanson, L. and Shaw, J. D. and Sparrow, M.D. and Summerhayes, C. and Terauds, A. and Diana H. Wall} } @article {1108, title = {Cross-biome metagenomic analyses of soil microbial communities and their functional attributes}, journal = {Proceedings Bational Academy of Sciences}, year = {2012}, month = {11/2012}, keywords = {LTER-MCM}, doi = {10.1073/pnas.1215210110}, url = {www.pnas.org/cgi/doi/10.1073/pnas.1215210110}, author = {Noah Fierer and Jonathan W. Leff and Byron Adams and Uffe N. Nielsen and Scott T. Bates and Christian L. Lauber and Sarah Owens and Jack A. Gilbert and Diana H. Wall and J. Gregory Caporaso} } @article {1119, title = {The Disappearing Cryosphere: Impacts and Ecosystem Responses to Rapid Cryosphere Loss}, journal = {BioScience}, volume = {62}, year = {2012}, month = {04/2012}, pages = {405 - 415}, keywords = {LTER-MCM}, doi = {10.1525/bio.2012.62.4.11}, url = {http://bioscience.oxfordjournals.org/content/62/4/405.full}, author = {Andrew G Fountain and John L. Campbell and Edward A. G. Schuur and Sharon E. Stammerjohn and Mark W. Williams and Hugh W. Ducklow} } @article {1121, title = {Hypersaline {\textquotedblleft}wet patches{\textquotedblright} in Taylor Valley, Antarctica}, journal = {Geophysical Research Letters}, volume = {39}, year = {2012}, month = {03/2012}, keywords = {LTER-MCM}, doi = {10.1029/2012GL050898}, author = {Joseph S. Levy and Andrew G Fountain and Kathleen A. Welch and W. Berry Lyons} } @article {3528, title = {Microbial life at -13 ~C in the brine of an ice-sealed Antarctic lake}, journal = {Proceedings of the National Academy of Sciences}, volume = {109}, year = {2012}, month = {12/2012}, pages = {20626 - 20631}, keywords = {LTER-MCM}, issn = {0027-8424}, doi = {10.1073/pnas.1208607109}, url = {http://www.pnas.org/cgi/doi/10.1073/pnas.1208607109}, author = {A. E. Murray and Kenig, Fabien and Christian H. Fritsen and Christopher P. McKay and Kaelin M. Cawley and R. L. Edwards and Kuhn, Emanuele and Diane M. McKnight and Nathaniel E Ostrom and Vivian Peng and Adrian Ponce and John C. Priscu and Samarkin, Vladimir A. and Ashley T Townsend and Protima Wagh and Seth A Young and Pung To Yung and Peter T. Doran} } @book {1123, title = {Poisson Reconstruction of Extreme Submersed Environments: The ENDURANCE Exploration of an Under-Ice Antarctic Lake}, series = {Advances in Visual Computing. ISVC 2012. Lecture Notes in Computer Science.}, volume = {7431}, year = {2012}, pages = {394 - 403}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Berlin, Heidelberg}, abstract = {

We evaluate the use of Poisson reconstruction to generate a 3D bathymetric model of West Lake Bonney, Antarctica. The source sonar dataset has been collected by the ENDURANCE autonomous ve- hicle in the course of two Antarctic summer missions. The reconstruction workflow involved processing 200 million datapoints to generate a high resolution model of the lake bottom, Narrows region and underwater glacier face. A novel and flexible toolset has been developed to automate the processing of the Bonney data.

}, keywords = {LTER-MCM}, isbn = {978-3-642-33179-4}, doi = {10.1007/978-3-642-33179-4_38}, url = {http://www.springerlink.com/content/hg97w43588229087/}, author = {Alessandro Febretti and Kristof Richmond and Gulati, Shilpa and Flesher, Christopher and Hogan, Bartholomew P. and Andrew Johnson and Stone, William C. and John C. Priscu and Peter T. Doran}, editor = {Bebis, George and Boyle, Richard and Parvin, Bahram and Koracin, Darko and Fowlkes, Charless and Wang, Sen and Choi, Min-Hyung and Mantler, Stephan and Schulze, J{\"u}rgen and Acevedo, Daniel and Mueller, Klaus and Papka, Michael} } @article {4062, title = {Seismic multiplet response triggered by melt at Blood Falls, Taylor Glacier, Antarctica}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {117}, year = {2012}, month = {07/2012}, abstract = {

Meltwater input often triggers a seismic response from glaciers and ice sheets. It is difficult, however, to measure melt production on glaciers directly, while subglacial water storage is not directly observable. Therefore, we document temporal changes in seismicity from a dry-based polar glacier (Taylor Glacier, Antarctica) during a melt season using a synthesis of seismic observation and melt modeling. We record icequakes using a dense six-receiver network of three-component geophones and compare this with melt input generated from a calibrated surface energy balance model. In the absence of modeled surface melt, we find that seismicity is well-described by a diurnal signal composed of microseismic events in lake and glacial ice. During melt events, the diurnal signal is suppressed and seismicity is instead characterized by large glacial icequakes. We perform network-based correlation and clustering analyses of seismic record sections and determine that 18\% of melt-season icequakes are repetitive (multiplets). The epicentral locations for these multiplets suggest that they are triggered by meltwater produced near a brine seep known as Blood Falls. Our observations of the correspondingp-wave first motions are consistent with volumetric source mechanisms. We suggest that surface melt enables a persistent pathway through this cold ice to an englacial fracture system that is responsible for brine release episodes from the Blood Falls seep. The scalar moments for these events suggest that the volumetric increase at the source region can be explained by melt input.

}, keywords = {LTER-MCM}, doi = {10.1029/2011JF002221}, url = {http://onlinelibrary.wiley.com/doi/10.1029/2011JF002221/full}, author = {Carmichael, J. D. and Pettit, E. and Hoffman, M and Andrew G Fountain and Hallet, B.} } @article {1130, title = {15N and 13C{14N} NMR investigation of the major nitrogen-containing segment in an aquatic fulvic acid: Evidence for a hydantoin derivative}, journal = {Magnetic Resonance in Chemistry}, volume = {49}, year = {2011}, month = {12/2011}, pages = {775 - 780}, keywords = {LTER-MCM}, doi = {10.1002/mrc.2816}, author = {Xiaowen Fang and Jingdong Mao and Rose M. Cory and Diane M. McKnight and Klaus Schmidt-Rohr} } @article {1128, title = {Bacterial Community Structure Along Moisture Gradients in the Parafluvial Sediments of Two Ephemeral Desert Streams}, journal = {Microbial Ecology}, volume = {61}, year = {2011}, month = {4/2011}, pages = {543 - 556}, keywords = {LTER-MCM}, doi = {10.1007/s00248-010-9782-7}, url = {http://www.springerlink.com/content/r83j53334v5n505w/}, author = {Lydia H. Zeglin and Clifford N. Dahm and John E. Barrett and Michael N. Gooseff and Shannon K. Fitpatrick and Cristina D. Takacs-Vesbach} } @article {1140, title = {Determination of Dissolved Oxygen in the Cryosphere: A Comprehensive Laboratory and Field Evaluation of Fiber Optic Sensors}, journal = {Environmental Science \& Technology}, volume = {45}, year = {2011}, month = {01/2011}, pages = {700 - 705}, keywords = {LTER-MCM}, doi = {10.1021/es102571j}, author = {Bagshaw, Elizabeth and Wadham, J. L. and Mowlem, M. and Martyn Tranter and Eveness, J. and Andrew G Fountain and Telling, J.} } @article {1137, title = {High-resolution monitoring reveals dissolved oxygen dynamics in an Antarctic cryoconite hole}, journal = {Hydrological Processes}, volume = {25}, year = {2011}, month = {08/2011}, pages = {2868 - 2877}, keywords = {LTER-MCM}, doi = {10.1002/hyp.8049}, author = {Bagshaw, Elizabeth and Martyn Tranter and Wadham, J. L. and Andrew G Fountain and Mowlem, M.} } @article {1135, title = {Hydrological Connectivity of the Landscape of the McMurdo Dry Valleys, Antarctica}, journal = {Geography Compass}, volume = {5}, year = {2011}, month = {09/2011}, pages = {666 - 681}, keywords = {LTER-MCM}, doi = {10.1111/j.1749-8198.2011.00445.x}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1749-8198.2011.00445.x}, author = {Michael N. Gooseff and Diane M. McKnight and Peter T. Doran and Andrew G Fountain and W. Berry Lyons} } @article {1125, title = {Protist diversity in a permanently ice-covered Antarctic Lake during the polar night transition}, journal = {The ISME Journal}, volume = {5}, year = {2011}, month = {9/2011}, pages = {1559 - 1564}, keywords = {LTER-MCM}, doi = {10.1038/ismej.2011.23}, url = {http://www.nature.com/ismej/journal/v5/n9/abs/ismej201123a.html}, author = {Scott Bielewicz and Elanor R. Bell and Weidong Kong and Iddo Friedberg and John C. Priscu and Rachael M. Morgan-Kiss} } @article {1133, title = {Water tracks and permafrost in Taylor Valley, Antarctica: Extensive and shallow groundwater connectivity in a cold desert ecosystem}, journal = {Geological Society of America Bulletin}, volume = {123}, year = {2011}, month = {11/2011}, pages = {2295-2311}, keywords = {LTER-MCM}, doi = {10.1130/B30436.1}, url = {http://bulletin.geoscienceworld.org/content/123/11-12/2295.short}, author = {Joseph S. Levy and Andrew G Fountain and Michael N. Gooseff and Kathleen A. Welch and W. Berry Lyons} } @article {1138, title = {When a habitat freezes solid: microorganisms over-winter within the ice column of a coastal Antarctic lake}, journal = {FEMS Microbiology Ecology}, volume = {76}, year = {2011}, month = {06/2011}, pages = {401 - 412}, keywords = {LTER-MCM}, doi = {10.1111/j.1574-6941.2011.01061.x}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1574-6941.2011.01061.x/full}, author = {Christine M. Foreman and Markus Dieser and Mark Greenwood and Rose M. Cory and Johanna Laybourn-Parry and John T. Lisle and Chris Jaros and Penney L. Miller and Yu-Ping Chin and Diane M. McKnight} } @article {1151, title = {Antarctic lakes suggest millennial reorganizations of Southern Hemisphere atmospheric and oceanic circulation}, journal = {Proceedings of the National Academy of Sciences}, volume = {107}, year = {2010}, month = {12/2010}, pages = {21355 - 21359}, keywords = {LTER-MCM}, doi = {10.1073/pnas.1007250107}, url = {http://www.pnas.org/content/107/50/21355.full.pdf$\#$page=1\&view=FitH}, author = {Brenda L. Hall and George H. Denton and Andrew G Fountain and Chris H. Hendy and Gideon M. Henderson} } @inbook {1169, title = {The biogeochemistry and hydrology of Dry Valley glaciers: is there life on Martian ice now?}, booktitle = {Life in Antarctic Deserts and other Cold Dry Environments}, year = {2010}, pages = {195-220}, publisher = {Cambridge University Press}, organization = {Cambridge University Press}, address = {Cambridge}, keywords = {LTER-MCM}, author = {Martyn Tranter and Bagshaw, Elizabeth and Andrew G Fountain and Forman, C.} } @article {1157, title = {Design and deployment of a four-degrees-of-freedom hovering autonomous underwater vehicle for sub-ice exploration and mapping}, journal = {Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment}, volume = {224}, year = {2010}, month = {11/2010}, pages = {341 - 361}, keywords = {LTER-MCM}, doi = {10.1243/14750902JEME214}, author = {Stone, W and Bartholomew P Hogan and Flesher, C and Gulati, S and Kristof Richmond and Murarka, A and Kuhlman, G and Idharan, M and Siegel, V and Price, R M and Peter T. Doran and John C. Priscu} } @article {1162, title = {Dynamic behaviour of supraglacial lakes on cold polar glaciers: Canada Glacier, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {56}, year = {2010}, month = {06/2010}, pages = {366 - 368}, keywords = {LTER-MCM}, doi = {10.3189/002214310791968449}, author = {Bagshaw, Elizabeth and Martyn Tranter and Wadham, J. L. and Andrew G Fountain and Hassan J. Basagic} } @article {1165, title = {A dynamic physical model for soil temperature and water in Taylor Valley, Antarctica.}, journal = {Antarctic Science}, year = {2010}, month = {05/13/2010}, pages = {419-434}, type = {Journal}, keywords = {LTER-MCM}, doi = {10.1017/S0954102010000234}, author = {H. W. Hunt and Andrew G Fountain and Peter T. Doran and Hassan J. Basagic} } @mastersthesis {1230, title = {An Energy Balance Model of Melt-water Production for Polar Glaciers in Taylor Valley, Antarctica}, volume = {M.S.}, year = {2010}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Ebnet, J and Andrew G Fountain} } @article {1147, title = {Experimentally increased snow accumulation alters soil moisture and animal community structure in a polar desert}, journal = {Polar Biology}, volume = {33}, year = {2010}, month = {7/2010}, pages = {897 - 907}, keywords = {LTER-MCM}, doi = {10.1007/s00300-010-0766-3}, author = {Edward Ayres and Johnson N. Nkem and Diana H. Wall and Byron Adams and John E. Barrett and Breana L. Simmons and Ross A. Virginia and Andrew G Fountain} } @article {1166, title = {Snow in the McMurdo Dry Valleys, Antarctica.}, journal = {International Journal of Climatology}, volume = {30}, year = {2010}, month = {04/2010}, pages = {633-642}, type = {Journal}, abstract = {

Snowfall was measured at 11 sites in the McMurdo Dry Valleys to determine its magnitude, its temporal changes, and spatial patterns. Annual values ranged from 3 to 50 mm water equivalent with the highest values nearest the coast and decreasing inland. A particularly strong spatial gradient exists in Taylor Valley, probably resulting from local uplift conditions at the coastal margin and valley topography that limits migration inland. More snow occurs in winter near the coast, whereas inland no seasonal pattern is discernable. This may be due, again, to local uplift conditions, which are common in winter. We find no influence of the distance to the sea ice edge. Katabatic winds play an important role in transporting snow to the valley bottoms and essentially double the precipitation. That much of the snow accumulation sublimates prior to making a hydrologic contribution underscores the notion that the McMurdo Dry Valleys are indeed an extreme polar desert. Copyright \© 2009 Royal Meteorological Society

}, keywords = {LTER-MCM, Biggie}, doi = {10.1002/joc.1933}, author = {Andrew G Fountain and Thomas H. Nylen and Andrew Monaghan and Hassan J. Basagic and David Bromwich} } @conference {1164, title = {Toward autonomous scientific exploration of ice-covered lakes{\textemdash}Field experiments with the ENDURANCE AUV in an Antarctic Dry Valley}, booktitle = {2010 IEEE International Conference on Robotics and Automation (ICRA 2010)2010 IEEE International Conference on Robotics and Automation}, year = {2010}, month = {05/2010}, pages = {308 - 315}, publisher = {IEEE}, organization = {IEEE}, address = {Anchorage, AK}, keywords = {LTER-MCM}, isbn = {978-1-4244-5038-1}, doi = {10.1109/ROBOT.2010.5509224}, author = {Gulati, S and Kristof Richmond and Flesher, C and Bartholomew P Hogan and Murarka, A and Gregory Kuhlmann and Mohan Sridharan and Stone, W and Peter T. Doran} } @article {1159, title = {Viable microbes in ice: application of molecular assays to McMurdo Dry Valley lake ice communities}, journal = {Antarctic Science}, volume = {22}, year = {2010}, month = {10/2010}, pages = {470 - 476}, abstract = {

The permanent ice covers of the McMurdo Dry Valley lakes, Antarctica, are colonized by a diverse microbial assemblage. We collected ice cores from Lakes Fryxell, Hoare and Bonney. Propidium monoazide (PMA) was used in combination with quantitative PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE) to examine membrane integrity of prokaryotes in these extreme environments. PMA selectively penetrates cells with compromised membranes and modifies their DNA resulting in the suppression of PCR amplification. Our results based on analysis of 16S rRNA genes demonstrate that despite the hostile conditions of the Dry Valleys, the permanent ice covers of the lakes support a \‘potentially viable\’ microbial community. The level of membrane integrity, as well as diversity, was higher in samples where sediment was entrapped in the ice cover. Pronounced differences in the fraction of cells with intact and compromised cell membranes were found for Lake Fryxell and east lobe of Lake Bonney, both expressed in differences in DGGE banding patterns and qPCR signal reductions. Limitations in the ability to distinguish between intact or compromised cells occurred in samples from Lake Hoare and west lobe of Lake Bonney due to low DNA template concentrations recovered from the samples.

}, keywords = {LTER-MCM}, doi = {10.1017/S0954102010000404}, url = {http://journals.cambridge.org/action/displayAbstract?fromPage=online\&aid=7909836\&fileId=S0954102010000404}, author = {Markus Dieser and Nocker, Andreas and John C. Priscu and Christine M. Foreman} } @article {1184, title = {A Contemporary Microbially Maintained Subglacial Ferrous "Ocean"}, journal = {Science}, volume = {324}, year = {2009}, month = {04/2009}, pages = {397-400}, type = {Journal}, abstract = {

An active microbial assemblage cycles sulfur in a sulfate-rich, ancient marine brine beneath Taylor Glacier, an outlet glacier of the East Antarctic Ice Sheet, with Fe(III) serving as the terminal electron acceptor. Isotopic measurements of sulfate, water, carbonate, and ferrous iron and functional gene analyses of adenosine 5\′-phosphosulfate reductase imply that a microbial consortium facilitates a catalytic sulfur cycle. These metabolic pathways result from a limited organic carbon supply because of the absence of contemporary photosynthesis, yielding a subglacial ferrous brine that is anoxic but not sulfidic. Coupled biogeochemical processes below the glacier enable subglacial microbes to grow in extended isolation, demonstrating how analogous organic-starved systems, such as Neoproterozoic oceans, accumulated Fe(II) despite the presence of an active sulfur cycle.

}, keywords = {LTER-MCM, Biggie}, doi = {10.1126/science.1167350}, url = {http://www.sciencemag.org/content/324/5925/397.short}, author = {Jill A. Mikucki and Pearson, A and Johnston, D and Turchyn, A and Farquhar, J and Schrag, D and Anbar, A and John C. Priscu and Lee, P} } @article {1180, title = {Environmental DNA sequencing primers for eutardigrades and bdelloid rotifers}, journal = {BMC Ecology}, volume = {9}, year = {2009}, month = {11/2009}, pages = {25}, keywords = {LTER-MCM}, doi = {10.1186/1472-6785-9-25}, author = {Robeson, Michael S and Costello, Elizabeth K and Freeman, Kristen R and Whiting, Jeremy and Byron Adams and Martin, Andrew P and Schmidt, Steve K} } @article {1181, title = {Lakes and reservoirs as regulators of carbon cycling and climate}, journal = {Limnology and Oceanography}, volume = {54 part 2}, year = {2009}, month = {11/2009}, pages = {2298{\textendash}2314}, keywords = {LTER-MCM}, doi = {10.4319/lo.2009.54.6_part_2.2298}, url = {http://aslo.org/lo/toc/vol_54/issue_6_part_2/2298.pdf}, author = {Lars J. Tranvik and John A. Downing and James B. Cotner and Steven A. Loiselle and Robert G. Striegl and Thomas J. Ballatore and Peter Dillon and Kerri Finlay and Kenneth Fortino and Lesley B. Knoll and Pirkko L. Kortelainen and Tiit Kutser and Soren Larsen and Isabelle Laurion and Dina M. Leech and S. Leigh McCallister and Diane M. McKnight and John M. Melack and Erin Overholt and Jason A. Porter and Yves Prairie and William H. Renwick and Fabio Roland and Bradford S. Sherman and David W. Schindler and Sebastian Sobek and Alain Tremblay and Michael J. Vanni and Antonie M. Verschoor and Eddie von Wachenfeldt and Gesa A. Weyhenmeyer} } @inbook {1188, title = {Lakes of Antarctica}, booktitle = {Encyclopedia of Inland Waters volume 2}, year = {2009}, pages = {555-566}, publisher = {Elsevier Press}, organization = {Elsevier Press}, address = {Oxford}, keywords = {LTER-MCM}, doi = {LTER}, author = {John C. Priscu and Christine M. Foreman}, editor = {G.E. Likens} } @article {1198, title = {Managing for ocean biodiversity to sustain marine ecosystem services}, journal = {FRONTIERS IN ECOLOGY AND THE ENVIRONMENT}, volume = {7}, year = {2009}, pages = {204-211}, keywords = {LTER-MCM}, doi = {LTER}, author = {Palumbi, S and Norse, E and Stachowicz, J and Diana H. Wall and Sandifer, P and Allan, J and Beck, M and Fautin, D and Fogerty, M and Halpern, B and Incze, L and Leong, J} } @inbook {1206, title = {Antarctic subglacial water: origin, evolution, and ecology}, booktitle = {Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems}, year = {2008}, publisher = {Oxford University Press}, organization = {Oxford University Press}, address = {Oxford}, keywords = {LTER-MCM}, author = {John C. Priscu and Tulaczyk, S and Studinger, M and Kenicutt, M and Brent C. Christner and Christine M. Foreman} } @inbook {1207, title = {Bacteria in Subglacial Environments}, booktitle = {Psychrophiles: from biodiversity to biotechnology}, year = {2008}, pages = {51-71}, publisher = {Springer Verlag}, organization = {Springer Verlag}, address = {New York}, keywords = {LTER-MCM}, author = {Brent C. Christner and Skidmore, M and John C. Priscu and Martyn Tranter and Christine M. Foreman} } @inbook {1209, title = {Biogeochemical processes in high-latitude lakes and rivers}, booktitle = {Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems}, year = {2008}, publisher = {Oxford University Press}, organization = {Oxford University Press}, address = {Oxford}, keywords = {LTER-MCM}, doi = {LTER}, author = {W. Berry Lyons and Finlay, J}, editor = {Warwick F. Vincent and Johanna Laybourn-Parry} } @article {1212, title = {Entry approach into pristine ice-sealed lakes - Lake Vida, East Antarctica, a model ecosystem}, journal = {Limnology and Oceanography-Methods}, volume = {6}, year = {2008}, pages = {542-547}, keywords = {LTER-MCM}, doi = {LTER}, author = {Peter T. Doran and Christian H. Fritsen and A. E. Murray and Kenig, Fabien and Christopher P. McKay and Kyne, J} } @phdthesis {1231, title = {The geochemistry of glacier snow and melt: The Oregon Cascades and Taylor Valley, Antarctica.}, volume = {Ph.D.}, year = {2008}, school = {The Ohio State University}, type = {doctoral}, keywords = {LTER-MCM}, doi = {LTER}, author = {Sarah Fortner} } @inbook {1213, title = {Glacial ecosystems}, booktitle = {Ecological Monographs}, volume = {78}, year = {2008}, pages = {41-67}, edition = {1}, abstract = {
There is now compelling evidence that microbially mediated reactions impart a significant effect upon the dynamics, composition, and abundance of nutrients in glacial melt water. Consequently, we must now consider ice masses as ecosystem habitats in their own right and address their diversity, functional potential, and activity as part of alpine and polar environments. Although such research is already underway, its fragmentary nature provides little basis for developing modern concepts of glacier ecology. This paper therefore provides a much-needed framework for development by reviewing the physical, biogeochemical, and microbiological characteristics of microbial habitats that have been identified within glaciers and ice sheets. Two key glacial ecosystems emerge, one inhabiting the glacier surface (the supraglacial ecosystem) and one at the ice-bed interface (the subglacial ecosystem). The supraglacial ecosystem is characterized by a diverse consortium of microbes (usually bacteria, algae, phytoflagellates, fungi, viruses and occasional rotifers, tardigrades, and diatoms) within the snowpack, supraglacial streams, and melt pools (cryoconite holes). The subglacial system is dominated by aerobic/anaerobic bacteria and most probably viruses in basal ice/till mixtures and subglacial lakes. A third, so-called englacial ecosystem is also described, but it is demonstrated that conditions within glacier ice are sufficient to make metabolic activity and its impact upon nutrient dynamics negligible at the glacier scale.
Consideration of the surface and internal heat balances of the glacier show that all glacial ecosystems are sensitive to climate change, although at different timescales. Thus, while rapid, melt-driven habitat changes lead to melt-out, resuscitation, and redistribution of microorganisms in many supraglacial ecosystems, much slower climatic and glacial mass-balance processes effect such changes in the subglacial ecosystem. Paradoxically, it is shown that these forces have brought about net refreezing and the onset of cryostasis in the subglacial ecosystems of many Arctic glaciers subject to thinning in recent decades.
}, keywords = {LTER-MCM, Biggie, snow ecology}, doi = {10.1890/07-0187.1}, url = {http://dx.doi.org/10.1890/07-0187.1}, author = {Hodson, A and Alexandre M. Anesio and Martyn Tranter and Andrew G Fountain and Osborn, M and John C. Priscu and Johanna Laybourn-Parry and Sattler, B} } @article {1202, title = {Global decomposition experiment shows soil animal impacts on decomposition are climate dependent}, journal = {Global Change Biology}, volume = {14}, year = {2008}, month = {11/2008}, pages = {2661-2677}, keywords = {LTER-MCM}, doi = {10.1111/j.1365-2486.2008.01672.x}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2008.01672.x/full}, author = {Diana H. Wall and Mark A. Bradford and Mark G. StJohn and John A. Trofymow and Valerie Behan-Pelletier and David E. Bignell and J. Mark Dangerfield and William J. Parton and Josef Rusek and Winfried Voigt and Volkmar Wolters and Holley Zadeh Gardel and Fred O. Ayuke and Richard Bashford and Olga I. Beljakova and Patrick J. Bohlen and Alain Brauman and Stephen Flemming and Joh R. Henschel and Dan L. Johnson and T. Hefin Jones and Marcela Kovarova and J. Marty Kranabetter and Les Kutny and Kuo-Chuan Lin and Mohamed Maryati and Dominique Masse and Andrei Pokarzhevskii and Homathevi Rahman and Millor G. Sabara and Joerg-Alfred Salamon and Michael J. Swift and Amanda Varela and Heraldo L. Vasconcelos and Don White and Xiaming Zou} } @article {1204, title = {Hydrologic response to extreme warm and cold summers in the McMurdo Dry Valleys, East Antarctica}, journal = {Antarctic Science}, volume = {20}, year = {2008}, month = {05/16/2008}, pages = {499-509}, type = {Journal}, keywords = {LTER-MCM, Climate Response, streams}, doi = {10.1017/S0954102008001272}, author = {Peter T. Doran and Christopher P. McKay and Andrew G Fountain and Thomas H. Nylen and Diane M. McKnight and Chris Jaros and John E. Barrett} } @inbook {1215, title = {Ice-based freshwater ecosystems}, booktitle = {Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems}, year = {2008}, publisher = {Oxford University Press}, organization = {Oxford University Press}, address = {Oxford}, keywords = {LTER-MCM}, doi = {LTER}, author = {Ian Hawes and Clive Howard-Williams and Andrew G Fountain}, editor = {Warwick F. Vincent and Johanna Laybourn-Parry} } @article {1217, title = {Introduction - The Biogeochemistry of Cryoconite Holes}, journal = {Journal of Geophysical Research}, volume = {113}, year = {2008}, keywords = {LTER-MCM}, doi = {10.1029/2008JG000698}, author = {Andrew G Fountain and Martyn Tranter} } @article {1224, title = {Stoichiometry of soil enzyme activity at global scale.}, journal = {Ecology Letters}, volume = {11}, year = {2008}, pages = {1252-1264}, keywords = {LTER-MCM}, doi = {LTER}, author = {Sinsabaugh, R and Gallo, M and Gartner, T and Hobbie, S and Holland, K and Keeler, B and Powers, J and Stursova, M and Cristina D. Takacs-Vesbach and Waldrop, M and Wallenstein, M and Lauber, M and Zak, D and Lydia H. Zeglin and Weintraub, M and Ahmed, B and Allison, S and Crenshaw, C and Contosta, A and Cusack, D and Frey, S} } @article {1226, title = {Surface energy balance and melt thresholds over 11 years at Taylor Glacier, Antarctica}, journal = {Journal of Geophysical Research-Earth Surface}, volume = {113}, year = {2008}, keywords = {LTER-MCM}, doi = {10.1029/2008JF001029}, author = {Hoffman, M and Andrew G Fountain and Liston, G} } @article {1227, title = {Temporal variations in physical and chemical features of cryoconite holes on Canada Glacier, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Geophysical Research}, volume = {113}, year = {2008}, pages = {G01S92}, keywords = {LTER-MCM}, doi = {10.1029/2008JG000698}, author = {Andrew G Fountain and Thomas H. Nylen and Martyn Tranter and Bagshaw, Elizabeth} } @article {1239, title = {The biogeochemical evolution of cryoconite holes on glaciers in Taylor Valley, Antarctica}, journal = {Journal of Geophysical Research}, volume = {113}, year = {2007}, pages = {G04S35}, keywords = {LTER-MCM}, doi = {LTER}, author = {Bagshaw, Elizabeth and Martyn Tranter and Andrew G Fountain and Kathleen A. Welch and Hassan J. Basagic and W. Berry Lyons} } @article {1236, title = {Biogeochemical stoichiometry of Antarctic Dry Valley ecosystems}, journal = {Journal of Geophysical Research}, volume = {112}, year = {2007}, month = {02/2007}, pages = {G01010+12}, abstract = {

Among aquatic and terrestrial landscapes of the McMurdo Dry Valleys, Antarctica, ecosystem stoichiometry ranges from values near the Redfield ratios for C:N:P to nutrient concentrations in proportions far above or below ratios necessary to support balanced microbial growth. This polar desert provides an opportunity to evaluate stoichiometric approaches to understand nutrient cycling in an ecosystem where biological diversity and activity are low, and controls over the movement and mass balances of nutrients operate over 10\–106\ years. The simple organisms (microbial and metazoan) comprising dry valley foodwebs adhere to strict biochemical requirements in the composition of their biomass, and when activated by availability of liquid water, they influence the chemical composition of their environment according to these ratios. Nitrogen and phosphorus varied significantly in terrestrial and aquatic ecosystems occurring on landscape surfaces across a wide range of exposure ages, indicating strong influences of landscape development and geochemistry on nutrient availability. Biota control the elemental ratio of stream waters, while geochemical stoichiometry (e.g., weathering, atmospheric deposition) evidently limits the distribution of soil invertebrates. We present a conceptual model describing transformations across dry valley landscapes facilitated by exchanges of liquid water and biotic processing of dissolved nutrients. We conclude that contemporary ecosystem stoichiometry of Antarctic Dry Valley soils, glaciers, streams, and lakes results from a combination of extant biological processes superimposed on a legacy of landscape processes and previous climates.

}, keywords = {LTER-MCM, Biggie}, doi = {10.1029/2005JG000141}, author = {John E. Barrett and Ross A. Virginia and W. Berry Lyons and Diane M. McKnight and John C. Priscu and Andrew G Fountain and Diana H. Wall and Daryl L. Moorhead and Peter T. Doran} } @article {1245, title = {Metabolic activity and diversity of cryoconites in the Taylor Valley, Antarctica}, journal = {Journal of Geophysical Research}, volume = {112}, year = {2007}, keywords = {LTER-MCM}, doi = {LTER}, author = {Christine M. Foreman and Sattler, B and Jill A. Mikucki and Porazinska, D and John C. Priscu} } @article {1237, title = {Solute and isotope geochemistry of subsurface ice melt seeps in Taylor Valley, Antarctica}, journal = {Geological Society of America Bulletin}, volume = {119}, year = {2007}, month = {01/2007}, pages = {548-555}, keywords = {LTER-MCM, Climate Response}, doi = {10.1130/B25913.1}, url = {http://gsabulletin.gsapubs.org/content/119/5-6/548.short}, author = {Harris, K and Anne E. Carey and Kathleen A. Welch and W. Berry Lyons and Andrew G Fountain} } @article {1259, title = {The aeolian flux of calcium, chloride and nitrate to the McMurdo Dry Valleys landscape: Evidence from snow pit analysis}, journal = {Antarctic Science}, volume = {18}, year = {2006}, pages = {497-505}, keywords = {LTER-MCM}, doi = {LTER}, author = {Witherow, R and Bertler, N and Kathleen A. Welch and W. Berry Lyons and Paul A. Mayewski and Sneed, S and Thomas H. Nylen and Handley, M and Andrew G Fountain} } @article {1263, title = {Biotic interactions in Antarctic terrestrial ecosystems: Are they a factor?}, journal = {Soil Biology and Biochemistry}, volume = {38}, year = {2006}, pages = {3035-3040}, keywords = {LTER-MCM}, doi = {10.1016/j.soilbio.2006.04.026}, url = {http://www.sciencedirect.com/science/article/pii/S0038071706002173}, author = {Hogg, I and Diana H. Wall and Craig S Cary and Convey, K and Newsham, K and ODonnell, G and Byron Adams and Aislabie, J and Francesco Frati and Stevens, M} } @article {1265, title = {Diversity and distribution of Victoria Land biota}, journal = {Soil Biology and Biochemistry}, volume = {38}, year = {2006}, pages = {3003-3018}, keywords = {LTER-MCM}, doi = {10.1016/j.soilbio.2006.04.030}, url = {https://www.sciencedirect.com/science/article/abs/pii/S0038071706002215}, author = {Byron Adams and Connell, L and Peter Convey and Fell, J and Francesco Frati and Hogg, I and Newsham, K and O{\textquoteright}Donnell, A and Russell, N and Seppelt, R and Stevens, M and Richard D. Bardgett and Edward Ayres and Diana H. Wall and Aislabie, J and Bamforth, S and Bargagli, R and Craig S Cary and Cavacini, P} } @article {1267, title = {Experimental investigations into processes controlling stream and hyporheic temperatures, Fryxell Basin, Antarctica}, journal = {Advances in Water Resources}, volume = {29}, year = {2006}, pages = {130-153}, keywords = {LTER-MCM}, doi = {LTER}, author = {Cozzetto, K and Diane M. McKnight and Thomas H. Nylen and Andrew G Fountain} } @article {1269, title = {Glacial and postglacial sedimentation in the Fryxell basin, Taylor Valley, Southern Victoria Land, Antarctica}, journal = {Palaeography, Palaeoclimatology, Palaeoecology}, volume = {341}, year = {2006}, pages = {320}, keywords = {LTER-MCM}, doi = {LTER}, author = {Wagner, B and Melles, M and Peter T. Doran and Kenig, Fabien and Forman, S and Pierau, R and Allan, P} } @article {1270, title = {Glacier mass balances (1993-2001) Taylor Valley, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {52}, year = {2006}, pages = {451}, keywords = {LTER-MCM}, doi = {LTER}, author = {Andrew G Fountain and Thomas H. Nylen and MacClune, K and Gayle L. Dana} } @inbook {1273, title = {Pedogenic carbonate distribution within glacial till in Taylor Valley, Southern Victoria Land, Antarctica}, booktitle = {Paleoenvironmental Record and Applications of Calcretes and Palustrine Carbonates}, year = {2006}, pages = {89-103}, publisher = {Geological Society of America}, organization = {Geological Society of America}, keywords = {LTER-MCM}, doi = {10.1130/2006.2416(06)}, author = {Foley, K and W. Berry Lyons and John E. Barrett and Ross A. Virginia} } @article {1258, title = {A stable isotopic investigation of a polar desert hydrologic system, McMurdo Dry Valleys, Antarctica}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {38}, year = {2006}, month = {02/2006}, pages = {60-71}, keywords = {LTER-MCM}, doi = {10.1657/1523-0430(2006)038[0060:ASIIOA]2.0.CO;2}, author = {Michael N. Gooseff and W. Berry Lyons and Diane M. McKnight and Bruce H. Vaughn and Andrew G Fountain and Carolyn Dowling} } @article {1292, title = {The chemical composition of runoff from Canada Glacier, Antarctica: implications for glacier hydrology during a cool summer}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, pages = {15-19}, keywords = {LTER-MCM}, doi = {LTER}, author = {Martyn Tranter and Andrew G Fountain and W. Berry Lyons and Thomas H. Nylen and Kathleen A. Welch} } @article {1293, title = {Comment on {\textquoteleft}{\textquoteleft}El Ni{\~n}o suppresses Antarctic warming{\textquoteright}{\textquoteright} by N. Bertler et al.}, journal = {Geophysical Research Letters}, volume = {32}, year = {2005}, pages = {L07706}, keywords = {LTER-MCM, Tropical meteorology}, doi = {10.1029/2004GL021716}, author = {Peter T. Doran and Gary D. Clow and Christian H. Fritsen and Christopher P. McKay and Andrew N. Parsons and John C. Priscu and W. Berry Lyons and Walsh, J and Andrew G Fountain and Diane M. McKnight and Daryl L. Moorhead and Ross A. Virginia and Diana H. Wall} } @article {1294, title = {Dating water and solute additions to ice-covered Antarctic lakes}, journal = {Geochimica et Cosmochimica Acta}, volume = {69}, year = {2005}, pages = {A720}, keywords = {LTER-MCM}, author = {W. Berry Lyons and Carolyn Dowling and Kathleen A. Welch and Snyder, G and Robert J. Poreda and Peter T. Doran and Andrew G Fountain} } @inbook {1295, title = {Developing new perspectives from advances in soil biodiversity research}, booktitle = {Biological Diversity and Function in Soils}, year = {2005}, pages = {3-30}, publisher = {Cambridge University Press}, organization = {Cambridge University Press}, keywords = {LTER-MCM}, author = {Diana H. Wall and Fritter, A and E. A. Paul}, editor = {Richard D. Bardgett and M. B. Usher and D. W. Hopkins} } @article {1297, title = {The Geochemistry of Supraglacial Streams of Canada Glacier, Taylor Valley (Antarctica), and their Evolution into Proglacial Waters}, journal = {Aquatic Geochemistry}, volume = {11}, year = {2005}, pages = {391-412}, keywords = {LTER-MCM}, author = {Sarah Fortner and Martyn Tranter and Andrew G Fountain and W. Berry Lyons and Kathleen A. Welch} } @article {1298, title = {Glacial ice cores: a model system for developing extraterrestrial decontamination protocols}, journal = {Icarus}, volume = {174}, year = {2005}, pages = {572-584}, keywords = {LTER-MCM}, doi = {LTER}, url = {/reports/lakes/ChristnerEtAl2005Decontamination.pdf}, author = {Brent C. Christner and Jill A. Mikucki and Christine M. Foreman and Denson, J and John C. Priscu} } @article {1299, title = {Groundwater seeps in Taylor Valley Antarctica: An example of a subsurface melt event}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, pages = {200-206}, keywords = {LTER-MCM}, doi = {LTER}, author = {W. Berry Lyons and Kathleen A. Welch and Anne E. Carey and Diana H. Wall and Ross A. Virginia and Andrew G Fountain and Peter T. Doran and Csatho, B and Tremper, C} } @article {1290, title = {An index model of stream flow at below freezing-temperatures in Taylor Valley, Antarctica}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, month = {01/2005}, pages = {76-82}, type = {Journal}, keywords = {LTER-MCM, Climate Response}, doi = {10.3189/172756405781813519}, url = {http://dx.doi.org/10.3189/172756405781813519}, author = {Ebnet, A and Andrew G Fountain and Thomas H. Nylen} } @article {1303, title = {The origin of channels on lower Taylor Glacier, McMurdo Dry Valleys Antarctica and their implication for water runoff}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, pages = {1-7}, keywords = {LTER-MCM}, doi = {LTER}, author = {Johnston, R and Andrew G Fountain and Thomas H. Nylen} } @mastersthesis {1316, title = {Pedogenic Carbonate Distribution within Glacial Till in Taylor Valley, Southern Victoria Land, Antarctica}, volume = {M.S.}, year = {2005}, school = {The Ohio State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Foley, K} } @inbook {1304, title = {Perennial Antarctic lake ice: A refuge for cyanobacteria in an extreme environment}, booktitle = {Life in Ancient Ice}, year = {2005}, pages = {22-49}, publisher = {Princeton University Press}, organization = {Princeton University Press}, keywords = {LTER-MCM}, url = {http://www.montana.edu/lkbonney/DOCS/Publications/PriscuEtAl2005CyanobacteriaRefuge.pdf}, author = {John C. Priscu and Edward E. Adams and Hans W. Paerl and Christian H. Fritsen and John E. Dore and John T. Lisle and Craig F. Wolf and Jill A. Mikucki}, editor = {S. O. Rogers and J. Castello} } @article {1305, title = {Perturbation of hydrochemical conditions in natural microcosms entombed within Antarctic ice}, journal = {Ice and Climate News}, volume = {6}, year = {2005}, pages = {22-23}, keywords = {LTER-MCM}, author = {Martyn Tranter and Andrew G Fountain and Christian H. Fritsen and W. Berry Lyons and John C. Priscu and Stratham, P and Kathleen A. Welch} } @inbook {1306, title = {Polar lakes, streams, and springs as analogs for the hydrological cycle on Mars.}, booktitle = {Advances in Astrobiology and Biogeophysics}, year = {2005}, pages = {219-233}, publisher = {Springer Verlag}, organization = {Springer Verlag}, address = {Berlin, Heidelberg}, keywords = {LTER-MCM}, doi = {LTER}, url = {/reports/lakes/McKayEtAl2005StreamsSprings.pdf}, author = {Christopher P. McKay and Dale T. Andersen and Pollard, W and Heldmann, J and Peter T. Doran and Christian H. Fritsen and John C. Priscu} } @inbook {1307, title = {Polar Systems}, booktitle = {Millennium Ecosystem Assessment. Current State and Trends: Findings of the Condition and Trends Working Group}, year = {2005}, pages = {717-743}, publisher = {Island Press}, organization = {Island Press}, keywords = {LTER-MCM}, doi = {LTER}, author = {F. S. Chapin and McGuire, A and Nuttall, M and Ross A. Virginia and Young, O and Zimov, S and Christensen, T and Godduhn, A and Murphy, E and Diana H. Wall and Zockler, C and Berman, M and Callaghan, T and Peter Convey and A. S. Crepin and Danell, K and Hugh W. Ducklow and Forbes, B and Kofinas, G}, editor = {R. Hassan and R. Scholes and N. Ash} } @mastersthesis {1317, title = {A temperature-index model of stream flow in Taylor Valley, Antarctica}, volume = {M.S.}, year = {2005}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Ebnet, A} } @article {1323, title = {The Biodiversity and Biogeochemistry of Cryoconite Holes from McMurdo Dry Valley Glaciers, Antarctica}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {36}, year = {2004}, pages = {84-91}, keywords = {LTER-MCM}, author = {Porazinska, D and Andrew G Fountain and Thomas H. Nylen and Martyn Tranter and Ross A. Virginia and Diana H. Wall} } @article {1318, title = {Can warming induce advances of polar glaciers, Taylor Valley, Antarctica}, journal = {Journal of Glaciology}, volume = {50}, year = {2004}, month = {12/2004}, pages = {556-564}, keywords = {LTER-MCM}, doi = {10.3189/172756504781829701}, author = {Andrew G Fountain and Thomas A. Neumann and Paul L. Glenn and Trevor Chinn} } @article {1325, title = {Changes in fulvic acid redox state through the oxycline of a permanently ice-covered Antarctic lake}, journal = {Aquatic Sciences}, volume = {66}, year = {2004}, pages = {1-20}, keywords = {LTER-MCM}, author = {Fulton, J and Diane M. McKnight and Christine M. Foreman and Rose M. Cory and Stedmon, C and Blunt, E} } @article {1326, title = {Climatology of Katabatic Winds in the McMurdo Dry Valleys, Southern Victoria Land, Antarctica}, journal = {Journal of Geophysical Research}, volume = {109}, year = {2004}, keywords = {LTER-MCM}, author = {Thomas H. Nylen and Andrew G Fountain and Peter T. Doran} } @article {1327, title = {Cryoconite holes on polar glaciers and their importance for meltwater runoff}, journal = {Journal of Glaciology}, volume = {50}, year = {2004}, pages = {25-45}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Martyn Tranter and Thomas H. Nylen and Booth, D and Karen J. Lewis} } @mastersthesis {1350, title = {Development of large supraglacial channels in the polar environment}, volume = {M.S.}, year = {2004}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Johnston, R} } @article {1321, title = {Evolution of cryoconite holes and their contribution to meltwater runoff from glaciers in the McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {50}, year = {2004}, month = {01/2004}, pages = {35-45}, keywords = {LTER-MCM}, doi = {10.3189/172756504781830312}, author = {Andrew G Fountain and Martyn Tranter and Thomas H. Nylen and Karen J. Lewis and Derek R. Mueller} } @article {1331, title = {Extreme hydrochemical conditions in natural microcosms entombed within Antarctic ice.}, journal = {Hydrological Processes}, volume = {18}, year = {2004}, pages = {379-387}, keywords = {LTER-MCM}, author = {Martyn Tranter and Andrew G Fountain and Christian H. Fritsen and W. Berry Lyons and John C. Priscu and Stathan, P and Kathleen A. Welch} } @inbook {1332, title = {Geochronology of high latitude lake sediments}, booktitle = {Long-Term Environmental Change in Arctic and Antarctic Lakes}, year = {2004}, publisher = {Kluwer Academic Publishers}, organization = {Kluwer Academic Publishers}, keywords = {LTER-MCM}, author = {Wolf, A and Miller, G and Olsen, C and Forman, S and Peter T. Doran and Holmgren, S}, editor = {Pienitz, R and Douglas, Marianne S. V. and J.P. Smol} } @article {1333, title = {Geomicrobiology of Blood Fall: An iron-rich saline discharge at the terminus of the Taylor Glacier, Antarctica}, journal = {Aquatic Geochemistry}, volume = {10}, year = {2004}, pages = {199-200}, keywords = {LTER-MCM}, author = {Jill A. Mikucki and Christine M. Foreman and Sattler, B and W. Berry Lyons and John C. Priscu} } @article {1320, title = {Impact of episodic warming events on the physical, chemical and biological relationships of lakes in the McMurdo Dry Valleys, Antarctica}, journal = {Aquatic Geochemistry}, volume = {10}, year = {2004}, month = {09/2004}, pages = {239-268}, type = {Journal}, keywords = {LTER-MCM, Climate Response, stoichiometry}, doi = {10.1007/s10498-004-2261-3}, url = {http://link.springer.com/article/10.1007\%2Fs10498-004-2261-3}, author = {Christine M. Foreman and Wolf, C and John C. Priscu} } @article {1345, title = {Thermodynamic constraints on microbially mediated processes in lakes of the McMurdo Dry Valleys, Antarctica}, journal = {Geomicrobiology Journal}, volume = {21}, year = {2004}, pages = {1-17}, keywords = {LTER-MCM}, doi = {LTER}, author = {Lee, P and Jill A. Mikucki and Christine M. Foreman and John C. Priscu and G R DiTullio and Riseman, S and DeMora, S and Craig F. Wolf and Kester, L} } @inbook {1359, title = {Century to millennial scale climate change and ecosystem response in Taylor Valley, Antarctica}, booktitle = {Climate Variability and Ecosystem Response at Long-Term Ecological Research Sites}, series = {Long-Term Ecological Research Network}, year = {2003}, pages = {319-340}, publisher = {Oxford University Press}, organization = {Oxford University Press}, address = {New York City}, keywords = {LTER-MCM, Climate Response}, isbn = {0195150597}, author = {Andrew G Fountain and W. Berry Lyons}, editor = {D. Greenland and D. G. Goodin and R. C. Smith} } @article {1357, title = {Formation and character of an ancient 19 m ice cover and underlying trapped brine in an}, journal = {Proceedings of National Academy of Sciences}, volume = {100}, year = {2003}, month = {01/2003}, pages = {26-31}, type = {Journal}, keywords = {LTER-MCM}, doi = {10.1073/pnas.222680999}, url = {http://www.pnas.org/content/100/1/26.short}, author = {Peter T. Doran and Christian H. Fritsen and Christopher P. McKay and John C. Priscu and Edward E. Adams} } @article {1364, title = {Glaciers of the McMurdo Dry Valleys: terrestrial analog for Martian polar sublimation}, journal = {Journal of Geophysical Research}, volume = {108}, year = {2003}, pages = {5031}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Andrew G Fountain and Kargel, J and MacAyeal, D} } @article {1365, title = {Map-based methods for estimating glacier equilibrium-line altitudes}, journal = {Journal of Glaciology}, volume = {49}, year = {2003}, pages = {329-336}, keywords = {LTER-MCM}, doi = {LTER}, author = {Leonard, K and Andrew G Fountain} } @article {1369, title = {Surface glaciochemistry of Taylor Valley, southern Victoria Land, Antarctica and its relationship to stream chemistry.}, journal = {Hydrological Processes}, volume = {17}, year = {2003}, pages = {115-130}, keywords = {LTER-MCM}, author = {W. Berry Lyons and Kathleen A. Welch and Andrew G Fountain and Gayle L. Dana and Bruce H. Vaughn and Diane M. McKnight} } @article {1377, title = {Antarctic climate cooling and terrestrial ecosystem response}, journal = {Nature}, volume = {415}, year = {2002}, month = {01/2002}, pages = {517-520}, type = {Journal}, keywords = {LTER-MCM, Climate Response}, doi = {10.1038/nature710}, author = {Peter T. Doran and John C. Priscu and W. Berry Lyons and John E. Walsh and Andrew G Fountain and Diane M. McKnight and Daryl L. Moorhead and Ross A. Virginia and Diana H. Wall and Gary D. Clow and Christian H. Fritsen and Christopher P. McKay and Andrew N. Parsons} } @article {1378, title = {Direct observation of aluminosilicate weathering in the hyporheic zone of an Antarctic Dry Valley stream}, journal = {Geochimica et Cosmochimica Acta}, volume = {66}, year = {2002}, pages = {1335-1347}, keywords = {LTER-MCM}, author = {Maurice, P and Diane M. McKnight and Leff, L and Fulghun, J and Michael N. Gooseff} } @inbook {1380, title = {Extremophiles: ice ecosystems and biodiversity}, booktitle = {Knowledge for Sustainable Development: an Insight into the Encyclopedia of Life Support Systems.}, year = {2002}, pages = {573-598}, publisher = {UNESCO Publishing-Eolss Publishers}, organization = {UNESCO Publishing-Eolss Publishers}, address = {Oxford}, keywords = {LTER-MCM}, author = {Psenner, R and Felip, M and John C. Priscu and Wagenbach, D and Willie, A and Sattler, B} } @article {1382, title = {Recent Temperature Trends in the Antarctic}, journal = {Nature}, volume = {418}, year = {2002}, pages = {291-292}, keywords = {LTER-MCM}, author = {John E. Walsh and Gary D. Clow and Christian H. Fritsen and Christopher P. McKay and Andrew N. Parsons and Peter T. Doran and John C. Priscu and W. Berry Lyons and Andrew G Fountain and Diane M. McKnight and Daryl L. Moorhead and Ross A. Virginia and Diana H. Wall} } @article {1383, title = {Satellite-Derived Indices of Stream Discharge in Taylor Valley,Antarctica.}, journal = {Hydrological Processes}, volume = {16}, year = {2002}, pages = {1603-1616}, keywords = {LTER-MCM}, author = {Gayle L. Dana and Davis, R and Andrew G Fountain and Robert A. Wharton Jr.} } @article {1376, title = {Snow patch influence on soil biogeochemical processes and invertebrate distribution in the McMurdo Dry Valleys, Antarctica}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {35}, year = {2002}, month = {02/2003}, pages = {91-99}, type = {Journal}, keywords = {LTER-MCM, Biggie}, doi = {10.1657/1523-0430(2003)035[0091:SPIOSB]2.0.CO;2}, url = {http://instaar.metapress.com/content/r086455ju7213711/}, author = {Michael N. Gooseff and John E. Barrett and Peter T. Doran and Andrew G Fountain and W. Berry Lyons and Andrew N. Parsons and Porazinska, D and Ross A. Virginia and Diana H. Wall} } @article {1384, title = {Synthetic aperture radar detection of the snowline on Commonwealth and Howard Glaciers, Taylor Valley, Antarctica}, journal = {Annals of Glaciology}, volume = {34}, year = {2002}, pages = {177-183}, keywords = {LTER-MCM}, author = {Bardel, P and Andrew G Fountain and Hall, D and Kwok, R} } @article {1374, title = {Valley floor climate observations from the McMurdo Dry Valleys, Antarctica, 1986-2000}, journal = {Journal of Geophysical Research}, volume = {107}, year = {2002}, month = {12/2002}, pages = {4772-4784}, type = {Journal}, abstract = {

Climate observations from the McMurdo dry valleys, East Antarctica are presented from a network of seven valley floor automatic meteorological stations during the period 1986 to 2000. Mean annual temperatures ranged from \−14.8\°C to \−30.0\°C, depending on the site and period of measurement. Mean annual relative humidity is generally highest near the coast. Mean annual wind speed increases with proximity to the polar plateau. Site-to-site variation in mean annual solar flux and PAR is due to exposure of each station and changes over time are likely related to changes in cloudiness. During the nonsummer months, strong katabatic winds are frequent at some sites and infrequent at others, creating large variation in mean annual temperature owing to the warming effect of the winds. Katabatic wind exposure appears to be controlled to a large degree by the presence of colder air in the region that collects at low points and keeps the warm less dense katabatic flow from the ground. The strong influence of katabatic winds makes prediction of relative mean annual temperature based on geographical position (elevation and distance from the coast) alone, not possible. During the summer months, onshore winds dominate and warm as they progress through the valleys creating a strong linear relationship (r2\ = 0.992) of increasing potential temperature with distance from the coast (0.09\°C km\−1). In contrast to mean annual temperature, summer temperature lends itself quite well to model predictions, and is used to construct a statistical model for predicting summer dry valley temperatures at unmonitored sites.

}, keywords = {LTER-MCM, Biggie}, doi = {10.1029/2001JD002045}, author = {Peter T. Doran and Christopher P. McKay and Gary D. Clow and Gayle L. Dana and Andrew G Fountain and Thomas H. Nylen and W. Berry Lyons} } @phdthesis {1415, title = {Energy balance of a rough glacier surface, Canada Glacier, McMurdo Dry Valleys, Antarctica}, volume = {Ph.D.}, year = {2001}, school = {Portland State University}, type = {doctoral}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis} } @article {1416, title = {Glacial cryoconite ecosystems: a bipolar comparison of algal communities and habitats}, journal = {Nova Hedwigia}, volume = {123}, year = {2001}, pages = {173-197}, keywords = {LTER-MCM}, author = {Derek R. Mueller and Warwick F. Vincent and Pollard, W and Christian H. Fritsen} } @article {1405, title = {Mineralogical and geochemical analyses of Antarctic lake sediments: A study of reflectanceand Mossbauer spectroscopy and C, N and S isotopes with applications for remote sensing on Mars}, journal = {Geochimica et Cosmochimica Acta}, volume = {65}, year = {2001}, pages = {2875-2897}, keywords = {LTER-MCM}, author = {Bishop, Janice L. and Lougear, A and Newton, J and Peter T. Doran and Froeschl, H and Krner, W and Koeberl, C and Trautwein, A} } @mastersthesis {1420, title = {Synthetic aperture radar imagery of polar glaciers}, volume = {M.S.}, year = {2001}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Bardel, P} } @inbook {1426, title = {Climate and hydrologic variations and implications for lake and stream ecological response in the McMurdo Dry Valleys, Antarctica}, booktitle = {Climate Variability and Ecosystem Response at Long Term Ecological Research Sites}, year = {2000}, pages = {174-195}, publisher = {Oxford University Press}, organization = {Oxford University Press}, keywords = {LTER-MCM}, author = {Kathleen A. Welch and W. Berry Lyons and Diane M. McKnight and Chris Jaros and Andrew G Fountain and Thomas H. Nylen and Peter T. Doran and Clive Howard-Williams}, editor = {D. Greenland and D. G. Goodin and R. C. Smith} } @article {1428, title = {Distribution of organic carbon and nitrogen in surface soils in the McMurdo Dry Valleys, Antarctica.}, journal = {Polar Biology}, volume = {23}, year = {2000}, pages = {121-128}, keywords = {LTER-MCM}, author = {Christian H. Fritsen and Grue, A and John C. Priscu} } @inbook {1429, title = {Experimental Approaches to Investigate Belowground Animal Diversity}, booktitle = {Methods in Ecosystem Science}, year = {2000}, pages = {318-329}, publisher = {Springer Verlag}, organization = {Springer Verlag}, address = {New York}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Reichman, O}, editor = {Osvaldo E. Sala and Jackson, R and Mooney, H and R. Howarth} } @article {1432, title = {The importance of landscape position and legacy: The evolution of the Taylor Valley Lake District, Antarctica.}, journal = {Freshwater Biology}, volume = {43}, year = {2000}, pages = {355-367}, keywords = {LTER-MCM}, author = {W. Berry Lyons and Andrew G Fountain and Peter T. Doran and John C. Priscu and Klaus Neumann and Kathleen A. Welch} } @article {1442, title = {Nuclear and mitochondrial DNA sequence diversity in the Antarctic nematode Scottnema lindsayae}, journal = {Journal of Nematology}, volume = {322}, year = {2000}, pages = {143-153}, keywords = {LTER-MCM}, author = {Courtright, E and Diana H. Wall and Ross A. Virginia and Vida, J and Frisse, L and Thomas, W} } @article {1450, title = {Carbon transformations in a perennially ice-covered Antarctic lake}, year = {1999}, keywords = {LTER-MCM}, author = {John C. Priscu and Craig F. Wolf and Cristina D. Takacs-Vesbach and Christian H. Fritsen and Johanna Laybourn-Parry and Emily C. Roberts and Birgit Sattl} } @article {1460, title = {History of McMurdo Dry Valley Lakes, Antarctica, from stable chlorine isotope data}, journal = {Geology}, volume = {27}, year = {1999}, keywords = {LTER-MCM}, doi = {LTER}, author = {W. Berry Lyons and Frape, S and Kathleen A. Welch} } @article {1461, title = {The importance of terminus cliff melt on stream flow, Taylor Valley, McMurdo Dry Valleys}, journal = {Global and Planetary Change}, volume = {22}, year = {1999}, pages = {105-115}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis and Andrew G Fountain and Paul Langevin} } @article {1464, title = {Lake ice microbial communities in alpine and Antarctic lakes}, year = {1999}, keywords = {LTER-MCM}, author = {Psenner, R and Sattler, B and Willie, A and Christian H. Fritsen and John C. Priscu and Felip, M and J. Catalan} } @article {1447, title = {Physical controls on the Taylor Valley Ecosystem, Antarctica}, journal = {BioScience}, volume = {49}, year = {1999}, month = {12/1999}, pages = {961-972}, type = {Journal}, keywords = {LTER-MCM, Water availability}, author = {Andrew G Fountain and W. Berry Lyons and Melody B. Burkins and Gayle L. Dana and Peter T. Doran and Karen J. Lewis and Diane M. McKnight and Daryl L. Moorhead and Andrew N. Parsons and John C. Priscu and Diana H. Wall and Robert A. Wharton Jr. and Ross A. Virginia} } @article {1470, title = {Seasonal change in the optical properties of the permanent ice cover on Lake Bonney, Antarctica: Consequences for lake productivity and phytoplankton dynamics}, journal = {Limnology and Oceanography}, volume = {44}, year = {1999}, pages = {447-454}, keywords = {LTER-MCM}, author = {Christian H. Fritsen and John C. Priscu} } @article {1486, title = {Antarctic lake-ice microbial consortia: Origin, distribution, and growth physiology}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {223-224}, keywords = {LTER-MCM}, author = {John C. Priscu and Christian H. Fritsen} } @article {1490, title = {Cyanobacterial assemblages in permanent ice covers on Antarctic lakes: distribution, growth rate, and temperature response of photosynthesis}, journal = {Journal of Phycology}, volume = {34}, year = {1998}, pages = {587-597}, keywords = {LTER-MCM}, author = {Christian H. Fritsen and John C. Priscu} } @article {1494, title = {Distribution, Community Structure, and Microhabitats of Soil Invertebrates along an Elevational Gradient in Taylor Valley}, journal = {Alpine and Alpine Research}, volume = {30}, year = {1998}, pages = {133-141}, keywords = {LTER-MCM}, author = {Powers, Laura E. and Mengchi Ho and Diana W. Freckman and Ross A. Virginia} } @article {1495, title = {Energy balance studies of Canada Glacier, Taylor Valley, McMurdo Dry Valleys, Antarctica}, journal = {Annals of Glaciology}, volume = {27}, year = {1998}, pages = {603-609}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis and Andrew G Fountain and Gayle L. Dana} } @inbook {1498, title = {From the ground up: nematode ecology in bioassessment and ecosystem health}, booktitle = {Plant-Nematode Interactions(Agronomy Monograph)}, year = {1998}, keywords = {LTER-MCM}, author = {R. K. Niles and Diana W. Freckman} } @inbook {1500, title = {Glaciers of the McMurdo Dry Valleys, Southern Victoria Land, Antarctica}, booktitle = {Ecosystem Processes in a Polar Desert: The McMurdo Dry Valleys, Antarctica}, series = {Antarctic Research Series}, volume = {72}, year = {1998}, pages = {65-75}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Gayle L. Dana and Karen J. Lewis and Bruce H. Vaughn and Diane M. McKnight} } @inbook {1501, title = {Hydrologic Processes Influencing Streamflow Variation in Fryxell Basin, Antarctica}, booktitle = {Ecosystem Processes in a Polar Desert: The McMurdo Dry Valleys, Antarctica}, series = {Antarctic Research Series}, volume = {72}, year = {1998}, pages = {93-108}, keywords = {LTER-MCM}, author = {Peter A. Conovitz and Diane M. McKnight and Lee H. MacDonald and Andrew G Fountain}, editor = {Harold R. House} } @article {1510, title = {McMurdo Dry Valleys LTER: Genetic diversity of soil nematodes in the McMurdo Dry Valleys of Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {203-204}, keywords = {LTER-MCM}, author = {Courtright, Ericha M and Diana W. Freckman and Ross A. Virginia and W. Kelley Thomas} } @article {1512, title = {McMurdo Dry Valleys LTER: Solar radiation on glaciers in Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {191-193}, keywords = {LTER-MCM}, author = {Gayle L. Dana and Robert A. Wharton Jr. and Andrew G Fountain} } @article {1513, title = {McMurdo Dry Valleys LTER: Spatial variation of glacier mass balance in Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {194-195}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Karen J. Lewis and Gayle L. Dana} } @article {1514, title = {McMurdo Dry Valleys LTER: The role of terminus cliff melt in streamflow, Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {189-190}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Andrew G Fountain and Paul Langevin} } @article {1515, title = {Mercury speciation and distribution in a polar desert lake (Lake Hoare, Antarctica) and two glacial meltwater streams}, journal = {Science of the Total Environment}, volume = {213}, year = {1998}, pages = {229-237}, keywords = {LTER-MCM}, author = {Vandal, G.M. and R.P. Mason and Diane M. McKnight and W. Fitzgerald} } @article {1518, title = {Natural abundance of carbon and nitrogen isotopes in potential sources of organic matter to soils of Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {209-210}, keywords = {LTER-MCM}, author = {Melody B. Burkins and C. Page Chamberlain and Ross A. Virginia and Diana W. Freckman} } @article {1519, title = {Nitrogen fixation within permanent ice covers on lakes in the McMurdo Dry Valleys, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {218-220}, keywords = {LTER-MCM}, author = {Amanda M. Grue and Christian H. Fritsen and John C. Priscu} } @article {1482, title = {Perennial Antarctic Lake Ice: An Oasis for Life in a Polar Desert}, journal = {Science}, volume = {280}, year = {1998}, month = {06/1998}, pages = {2095-2098}, type = {Journal}, keywords = {LTER-MCM, Biggie}, doi = {10.1126/science.280.5372.2095}, url = {http://www.sciencemag.org/content/280/5372/2095.short}, author = {John C. Priscu and Christian H. Fritsen and Edward E. Adams and Stephen J. Giovannoni and Hans W. Paerl and Christopher P. McKay and Peter T. Doran and Douglas A. Gordon and Brian D. Lanoil and James L. Pinckney} } @inbook {1521, title = {Permanent Ice Covers of the McMurdo Dry Valley Lakes, Antarctica: Bubble Formation and Metamorphism}, booktitle = {Ecosystem Processes in a Polar Desert: The McMurdo Dry Valleys, Antarctica}, series = {Antarctic Research Series}, volume = {72}, year = {1998}, pages = {281-295}, keywords = {LTER-MCM}, author = {Edward E. Adams and John C. Priscu and Christian H. Fritsen and Scott R.Smith and Steven L. Brackman} } @inbook {1522, title = {Permanent Ice Covers of the McMurdo Dry Valleys Lakes, Antarctica: Liquid Water Contents}, booktitle = {Ecosystem Processes in a Polar Desert: The McMurdo Dry Valleys, Antarctica}, series = {Antarctic Research Series}, volume = {72}, year = {1998}, pages = {269-280}, keywords = {LTER-MCM}, author = {Christian H. Fritsen and Edward E. Adams and Christopher P. McKay and John C. Priscu} } @article {1523, title = {Photosynthetic characteristics of cyanobacteria in permanent ice covers on lakes in the McMurdo Dry Valleys, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {216-218}, keywords = {LTER-MCM}, author = {Christian H. Fritsen and John C. Priscu} } @article {1529, title = {Soil Biodiversity and Community Structure in the McMurdo Dry Valleys, Antarctica, in Ecosystem Processes in a Polar Desert: The McMurdo Dry Valleys, Antarctica}, journal = {Antarctic Research Series}, volume = {72}, year = {1998}, pages = {323-335}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Ross A. Virginia} } @article {1533, title = {Surface energy balance and meltwater production for a Dry Valley glacier, Taylor Valley, Antarctica}, journal = {Annals of Glaciology}, volume = {27}, year = {1998}, pages = {603-609}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Andrew G Fountain and Gayle L. Dana} } @inbook {1439, title = {A Temperature area index of stream discharge in Taylor Valley, Antarctica}, booktitle = {Applications of Remote Sensing in Hydrology}, year = {1998}, pages = {29-39}, publisher = {National Water Research Institute , Environment Canada}, organization = {National Water Research Institute , Environment Canada}, keywords = {LTER-MCM}, author = {Gayle L. Dana and Davis, R and Andrew G Fountain and Robert A. Wharton Jr.}, editor = {A. Pietroniro and R. Granger and T.J. Pultz} } @article {1545, title = {Biodiversity and Ecosystem Functioning in Soil}, journal = {Ambio}, volume = {26}, year = {1997}, pages = {563-570}, keywords = {LTER-MCM}, author = {Brussaard, L and Valerie Behan-Pelletier and David E. Bignell and V.K. Brown}, editor = {W. Didden and P. Folgarait and C. Fragoso and Diana W. Freckman} } @article {1547, title = {Carbon cycling in soils of the McMurdo Dry Valley region, Antarctica}, journal = {Bulletin of the Ecological Society of America Supplement}, volume = {78}, year = {1997}, pages = {230}, keywords = {LTER-MCM}, author = {Melody B. Burkins and Ross A. Virginia and Diana W. Freckman and C. Page Chamberlain} } @article {1556, title = {Linking biodiversity and ecosystem functioning of soils and sediments}, journal = {Ambio}, volume = {26}, year = {1997}, pages = {556-562}, keywords = {LTER-MCM}, author = {Diana W. Freckman and T.H. Blackburn and Brussaard, L and P. Hutchings and M.A. Palmer and P.V.R. Snelgrove} } @article {1558, title = {Low-diversity Antarctic soil nematode communities: distribution and response to disturbance}, journal = {Ecology}, volume = {78}, year = {1997}, pages = {363-369}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Ross A. Virginia} } @article {1542, title = {Open-top Designs for Manipulating Field Temperature in High-Latitude Ecosystems}, journal = {Global Change Biology}, volume = {3}, year = {1997}, month = {12/1997}, pages = {20-32}, keywords = {LTER-MCM}, doi = {10.1111/j.1365-2486.1997.gcb136.x}, author = {G. M. Marion and G.H.R. Henry and Diana W. Freckman and J. Johnstone and G. Jones and M.H. Jones and E. Levesque and U. Molau and P. M{\O}LGAARD and Andrew N. Parsons and J. Svoboda and Ross A. Virginia} } @article {1570, title = {Effects of human disturbance on soil nematode populations in Taylor Valley, Antarctica}, journal = {Bulletin of the Ecological Society of America Supplement}, volume = {77}, year = {1996}, pages = {360}, keywords = {LTER-MCM}, author = {Powers, Laura E. and Diana W. Freckman and Ross A. Virginia} } @inbook {1573, title = {Food-web dynamics and applied problems}, booktitle = {Food Webs: Integration of patterns and dynamics}, year = {1996}, pages = {327-336}, keywords = {LTER-MCM}, author = {L.B. Crowder and D.P. Reagan and Diana W. Freckman} } @article {1576, title = {Microcosms and Soil Ecology: Critical Linkages Between Field Studies and Modelling Food Webs}, journal = {Ecology}, volume = {77}, year = {1996}, pages = {694-705}, keywords = {LTER-MCM}, author = {John C. Moore and Peter C. De Ruiter and H. William Hunt and David C. Coleman and Diana W. Freckman} } @article {1580, title = {Reflectance spectroscopy and geochemical analyses of Lake Hoare sediments, Antarctica: Implications for remote sensing of the Earth and Mars}, journal = {Geochimica et Cosmochimica Acta}, volume = {60}, year = {1996}, pages = {765-785}, keywords = {LTER-MCM}, author = {Bishop, Janice L. and Koeberl, C and C. Kralik and H. Froschl}, editor = {P.A.J. Englert and Dale T. Andersen and C.M. Pieters and Robert A. Wharton Jr.} } @inbook {1581, title = {Soil invertebrates as indicators of soil quality}, booktitle = {Methods for assessing soil quality}, year = {1996}, publisher = {Soil Science Society of America}, organization = {Soil Science Society of America}, address = {Madison, WI}, keywords = {LTER-MCM}, author = {J.M. Blair and Patrick J. Bohlen and Diana W. Freckman}, editor = {J. W. Doran and A.J. Jones} } @article {1582, title = {Soil spatial variation along a toposequence in Taylor Valley, Antarctica}, journal = {Bulletin of the Ecological Society of America Supplement}, volume = {77}, year = {1996}, pages = {197}, keywords = {LTER-MCM}, author = {Mengchi Ho and Ross A. Virginia and Diana W. Freckman} } @mastersthesis {1586, title = {Surface energy balance and meltwater production for a dry valley glacier, Taylor Valley, Antarctica}, volume = {M.S.}, year = {1996}, school = {University of Colorado}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis} } @article {1593, title = {McMurdo LTER: Soil properties associated with nematode distribution along an elevational transect in Taylor Valley, Antarctica}, journal = {Antarctic Journal of the U.S.}, volume = {30}, year = {1995}, pages = {282-283}, keywords = {LTER-MCM}, author = {Powers, Laura E. and Diana W. Freckman and Mengchi Ho and Ross A. Virginia} } @article {1595, title = {McMurdo LTER: The surface-energy balance of the Canada Glacier, Taylor Valley}, journal = {Antarctic Journal of the United States}, volume = {30}, year = {1995}, pages = {280-282}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Gayle L. Dana and Scott W. Tyler and Andrew G Fountain} } @article {1603, title = {Soil chemistry along a glacial chronosequence on Andrews Ridge, Taylor Valley}, journal = {Antarctic Journal of the U.S.}, volume = {30}, year = {1995}, pages = {310-311}, keywords = {LTER-MCM}, author = {Mengchi Ho and Ross A. Virginia and Powers, Laura E. and Diana W. Freckman} } @article {1605, title = {Spatial Distribution of Nematodes in Polar Desert Soils of Antarctica}, journal = {Polar Biology}, volume = {15}, year = {1995}, pages = {325-333}, keywords = {LTER-MCM}, author = {Powers, Laura E. and Diana W. Freckman and Ross A. Virginia} } @article {1613, title = {Depth distribution of soil nematodes in Taylor Valley, Antarctica}, journal = {Antarctic Journal of the U.S.}, volume = {29}, year = {1994}, pages = {175-176}, keywords = {LTER-MCM}, author = {Powers, Laura E. and Diana W. Freckman and Ross A. Virginia} } @article {1616, title = {McMurdo LTER: Glacier mass balances of Taylor Valley, Antarctica}, journal = {Antarctic Journal of the U.S.}, volume = {29}, year = {1994}, pages = {226-228}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Bruce H. Vaughn and Gayle L. Dana} } @article {1618, title = {McMurdo LTER: Paleolimnology of Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States}, volume = {29}, year = {1994}, pages = {234-237}, keywords = {LTER-MCM}, doi = {LTER}, author = {Peter T. Doran and Robert A. Wharton Jr. and Sarah A. Spaulding and J. S. Foster} } @article {1622, title = {McMurdo LTER:Soil and nematode distribution along an elevational gradient in Taylor Valley, Antarctica}, journal = {Antarctic Journal of the U.S.}, volume = {29}, year = {1994}, pages = {228-229}, keywords = {LTER-MCM}, author = {Powers, Laura E. and Diana W. Freckman and Mengchi Ho and Ross A. Virginia} } @article {1624, title = {Nematode biodiversity and community structure in Antarctic Polar Desert Soils}, journal = {Bulletin of the Ecological Society of America}, volume = {75}, year = {1994}, pages = {186}, keywords = {LTER-MCM, Biggie}, author = {Powers, Laura E. and Diana W. Freckman and Ross A. Virginia} } @inbook {1625, title = {Nematode biodiversity and survival in Antarctic Dry Valley soils}, booktitle = {SCAR 6th Biology Symposium}, year = {1994}, address = {Venice, Italy}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Ross A. Virginia and Powers, Laura E.} } @article {1629, title = {Survival of Scottnema lindsayae under extreme osmotic conditions}, journal = {Society of Nematologists}, year = {1994}, keywords = {LTER-MCM}, author = {Powers, Laura E. and Diana W. Freckman and Ross A. Virginia} } @article {1633, title = {The ecology of nematodes in Antarctic Dry Valley soils}, journal = {Antarctic Journal of the U.S.}, volume = {28}, year = {1993}, pages = {10-11}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Ross A. Virginia} } @article {1635, title = {Extraction of nematodes from Dry Valley Antarctic soils}, journal = {Polar Biology}, volume = {13}, year = {1993}, pages = {483-487}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Ross A. Virginia} } @article {1638, title = {Life Cycle of the Microbivorous Antarctic Dry Valley Nematode Scottnema lindsaye Timm 1971}, journal = {Polar Biology}, volume = {13}, year = {1993}, pages = {151-156}, keywords = {LTER-MCM}, author = {A. Overhoff and Diana W. Freckman and Ross A. Virginia} } @article {1649, title = {Nematodes and soil properties in the Dry Valleys of southern Victoria Land, Antarctica}, journal = {Bulletin of the Ecological Society of America}, volume = {73}, year = {1992}, pages = {179}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Ross A. Virginia} } @article {1650, title = {Nematodes in Antarctic Dry Valley soils: extraction and distribution}, journal = {Journal of Nematology}, volume = {24}, year = {1992}, pages = {591}, keywords = {LTER-MCM}, author = {Diana W. Freckman and Ross A. Virginia} } @article {1653, title = {Nematodes in the McMurdo Dry Valleys of Southern Victoria Land}, journal = {Antarctic Journal of the United States}, volume = {26}, year = {1991}, pages = {233-234}, keywords = {LTER-MCM}, doi = {LTER}, author = {Diana W. Freckman and Ross A. Virginia} } @inbook {1655, title = {Glaciers of the southern hemisphere}, booktitle = {Global and Planetary Change}, volume = {22}, year = {1990}, keywords = {LTER-MCM}, doi = {LTER}, author = {Andrew G Fountain} } @article {1656, title = {Nematode Ecology of the McMurdo Dry Valley Ecosystems}, journal = {Antarctic Journal of the United States}, volume = {25}, year = {1990}, pages = {229-230}, keywords = {LTER-MCM}, doi = {LTER}, author = {Diana W. Freckman and Ross A. Virginia} }