<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Power, Sarah N.</style></author><author><style face="normal" font="default" size="100%">Salvatore, Mark R.</style></author><author><style face="normal" font="default" size="100%">Eric R. Sokol</style></author><author><style face="normal" font="default" size="100%">Lee F. Stanish</style></author><author><style face="normal" font="default" size="100%">Borges, Schuyler R.</style></author><author><style face="normal" font="default" size="100%">Byron Adams</style></author><author><style face="normal" font="default" size="100%">John E. Barrett</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Remotely characterizing photosynthetic biocrust in snowpack-fed microhabitats of Taylor Valley, Antarctica</style></title><secondary-title><style face="normal" font="default" size="100%">Science of Remote Sensing</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Antarctica</style></keyword><keyword><style  face="normal" font="default" size="100%">biocrust</style></keyword><keyword><style  face="normal" font="default" size="100%">carbon</style></keyword><keyword><style  face="normal" font="default" size="100%">reflectance spectroscopy</style></keyword><keyword><style  face="normal" font="default" size="100%">snow</style></keyword><keyword><style  face="normal" font="default" size="100%">soil ecology</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2024</style></year><pub-dates><date><style  face="normal" font="default" size="100%">02/2024</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://www.sciencedirect.com/science/article/pii/S266601722400004X</style></url></web-urls></urls><pages><style face="normal" font="default" size="100%">100120</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Microbial communities are the primary drivers of carbon cycling in the McMurdo Dry Valleys of Antarctica. Dense microbial mats, consisting mainly of photosynthetic cyanobacteria, occupy aquatic areas associated with streams and lakes. Other microbial communities also occur at lower densities as patchy surface biological soil crusts (hereafter, biocrusts) across the terrestrial landscape. Multispectral satellite data have been used to model microbial mat abundance in high-density areas like stream and lake margins, but no previous studies have investigated the lower detection limits of biocrusts. Here, we describe remote sensing and field-based survey and sampling approaches to study the detectability and distribution of biocrusts in the McMurdo Dry Valleys. Using a combination of multi- and hyperspectral tools and spectral linear unmixing, we modeled the abundances of biocrust in eastern Taylor Valley. Our spectral approaches can detect low masses of biocrust material in laboratory microcosms down to biocrust concentrations of 1% by mass. These techniques also distinguish the spectra of biocrust from both surface rock and mineral signatures from orbit. We found that biocrusts are present throughout the soils of eastern Taylor Valley and are associated with diverse underlying soil communities. The densest biocrust communities identified in this study had total organic carbon 5x greater than the content of typical arid soils. The most productive biocrusts were located downslope of melting snowpacks in unique soil ecosystems that are distinct from the surrounding arid landscape. There are similarities between the snowpack and stream sediment communities (high diversity of soil invertebrates) as well as their ecosystem properties (e.g., persistence of liquid water, high transfer of available nutrients, lower salinity from flushing) compared to the typical arid terrestrial ecosystem of the dry valleys. Our approach extends the capability of orbital remote sensing of photosynthetic communities out of the aquatic margins and into the drier soils which comprise most of this landscape. This interdisciplinary work is critical for measuring and monitoring terrestrial carbon stocks and predicting future ecosystem dynamics in this currently water-limited but increasingly dynamic Antarctic landscape, which is particularly climate-sensitive and difficult to access.&lt;/p&gt;</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dragone, Nicholas B.</style></author><author><style face="normal" font="default" size="100%">Henley, Jessica B.</style></author><author><style face="normal" font="default" size="100%">Holland-Moritz, Hannah</style></author><author><style face="normal" font="default" size="100%">Melisa A. Diaz</style></author><author><style face="normal" font="default" size="100%">Hogg, Ian D.</style></author><author><style face="normal" font="default" size="100%">W. Berry Lyons</style></author><author><style face="normal" font="default" size="100%">Diana H. Wall</style></author><author><style face="normal" font="default" size="100%">Byron Adams</style></author><author><style face="normal" font="default" size="100%">Noah Fierer</style></author></authors><secondary-authors><author><style face="normal" font="default" size="100%">Mackelprang, Rachel</style></author></secondary-authors></contributors><titles><title><style face="normal" font="default" size="100%">Elevational constraints on the composition and genomic attributes of microbial communities in Antarctic soils</style></title><secondary-title><style face="normal" font="default" size="100%">mSystems</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Antarctica</style></keyword><keyword><style  face="normal" font="default" size="100%">microbial ecology</style></keyword><keyword><style  face="normal" font="default" size="100%">soil microbiology</style></keyword><keyword><style  face="normal" font="default" size="100%">soils</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2022</style></year><pub-dates><date><style  face="normal" font="default" size="100%">01/2022</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://journals.asm.org/doi/full/10.1128/msystems.01330-21</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">e01330-21</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;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.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">George, Scott F.</style></author><author><style face="normal" font="default" size="100%">Noah Fierer</style></author><author><style face="normal" font="default" size="100%">Joseph S. Levy</style></author><author><style face="normal" font="default" size="100%">Byron Adams</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Antarctic water tracks: Microbial community responses to variation in soil moisture, pH, and salinity</style></title><secondary-title><style face="normal" font="default" size="100%">Frontiers in Microbiology</style></secondary-title><short-title><style face="normal" font="default" size="100%">Front. Microbiol.</style></short-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Antarctica</style></keyword><keyword><style  face="normal" font="default" size="100%">extremophiles</style></keyword><keyword><style  face="normal" font="default" size="100%">Mars analog</style></keyword><keyword><style  face="normal" font="default" size="100%">microbial ecology</style></keyword><keyword><style  face="normal" font="default" size="100%">water tracks</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2021</style></year><pub-dates><date><style  face="normal" font="default" size="100%">01/2021</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://www.frontiersin.org/articles/10.3389/fmicb.2021.616730</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">12</style></volume><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;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 (&amp;sim;5&amp;ndash;10 km&lt;sup&gt;2&lt;/sup&gt;) 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 &lt;em&gt;Bacteroidetes&lt;/em&gt; phylum being relatively more abundant at higher salinities and the &lt;em&gt;Actinobacteria&lt;/em&gt; 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.&lt;/p&gt;</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Melisa A. Diaz</style></author><author><style face="normal" font="default" size="100%">Welch, Susan A.</style></author><author><style face="normal" font="default" size="100%">Sheets, J. M.</style></author><author><style face="normal" font="default" size="100%">Kathleen A. Welch</style></author><author><style face="normal" font="default" size="100%">Khan, Alia L.</style></author><author><style face="normal" font="default" size="100%">Byron Adams</style></author><author><style face="normal" font="default" size="100%">Diane M. McKnight</style></author><author><style face="normal" font="default" size="100%">Craig S Cary</style></author><author><style face="normal" font="default" size="100%">W. Berry Lyons</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Geochemistry of aeolian material from the McMurdo Dry Valleys, Antarctica: Insights into Southern Hemisphere dust sources</style></title><secondary-title><style face="normal" font="default" size="100%">Earth and Planetary Science Letters</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">aeolian material</style></keyword><keyword><style  face="normal" font="default" size="100%">Antarctica</style></keyword><keyword><style  face="normal" font="default" size="100%">major oxides</style></keyword><keyword><style  face="normal" font="default" size="100%">mineralogy</style></keyword><keyword><style  face="normal" font="default" size="100%">rare earth elements</style></keyword><keyword><style  face="normal" font="default" size="100%">trace elements</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2020</style></year><pub-dates><date><style  face="normal" font="default" size="100%">10/2020</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://www.sciencedirect.com/science/article/pii/S0012821X20304040</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">547</style></volume><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;In the Southern Hemisphere, the major sources of dust and other aeolian materials are from Patagonia, South Africa, Australia, and New Zealand. Dust from Patagonia and New Zealand has been identified in ice cores throughout Antarctica, suggesting that during arid and windy periods, such as glacial periods, dust can be entrained and transported onto the continent. However, little information exists on modern Antarctic dust sources, transport, and its role in the Southern Hemisphere dust cycle. We present the first geochemical characterization of aeolian materials collected at five heights (between 5 cm and 100 cm) above the surface in four valleys within the McMurdo Dry Valleys, the largest ice-free area in Antarctica. Our mineralogy data indicate that these materials are primarily derived from local rocks of the McMurdo Volcanics, Ferrar Dolerite, Beacon Sandstone and Granite Harbor Intrusives, with varying contributions of each rock type dependent on the valley location. While major oxide, trace element and rare earth element data show that low elevation and coastal locations (with respect to the Ross Sea) are dominated by local sources, high elevation and inland locations have accumulated both local materials and dust from other distant Southern Hemisphere sources. This far-traveled material may not be accumulating today, but represents a paleo source that is resuspended from the soils. By geochemically &amp;ldquo;fingerprinting&amp;rdquo; aeolian materials from the MDV, we can better inform future studies on the transport of materials within Antarctica and between Southern Hemisphere land masses.&lt;/p&gt;</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Thompson, Andrew R.</style></author><author><style face="normal" font="default" size="100%">Geisen, Stefan</style></author><author><style face="normal" font="default" size="100%">Byron Adams</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Shotgun metagenomics reveal a diverse assemblage of protists in a model Antarctic soil ecosystem</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental Microbiology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Antarctica</style></keyword><keyword><style  face="normal" font="default" size="100%">extremophiles</style></keyword><keyword><style  face="normal" font="default" size="100%">functional groups</style></keyword><keyword><style  face="normal" font="default" size="100%">metagenomics</style></keyword><keyword><style  face="normal" font="default" size="100%">protozoa</style></keyword><keyword><style  face="normal" font="default" size="100%">soil microbiology</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2020</style></year><pub-dates><date><style  face="normal" font="default" size="100%">08/2020</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://sfamjournals.onlinelibrary.wiley.com/doi/abs/10.1111/1462-2920.15198</style></url></web-urls></urls><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The soils of the McMurdo Dry Valleys (MDV) of Antarctica are established models for understanding fundamental processes in soil ecosystem functioning (e.g. ecological tipping points, community structuring, and nutrient cycling) because the extreme physical environment drastically reduces biodiversity and ecological complexity. Understanding the functioning of MDV soils requires in‐depth knowledge of the diversity of MDV soil species. Protists, which contribute significantly to soil ecosystem functioning worldwide, remain poorly characterized in the MDV. To better assess the diversity of MDV protists, we performed shotgun metagenomics on 18 sites representing a variety of landscape features and edaphic variables. Our results show MDV soil protists are diverse at both the genus (155 of 281 eukaryote genera) and family (120) levels, but comprise only 6% of eukaryotic reads. Protists are structured by moisture, total N, and distance from the local coast, and possess limited richness in arid (&amp;lt;5% moisture) and at high elevation sites, known drivers of communities in the MDV. High relative diversity and broad distribution of protists in our study promotes these organisms as key members of MDV soil microbiomes and the MDV as a useful system for understanding the contribution of soil protists to the structure of soil microbiomes.&lt;/p&gt;</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wlostowski, Adam</style></author><author><style face="normal" font="default" size="100%">Schulte, Nicholas O.</style></author><author><style face="normal" font="default" size="100%">Byron Adams</style></author><author><style face="normal" font="default" size="100%">Ball, Becky</style></author><author><style face="normal" font="default" size="100%">Rhea M.M. Esposito</style></author><author><style face="normal" font="default" size="100%">Michael N. Gooseff</style></author><author><style face="normal" font="default" size="100%">W. Berry Lyons</style></author><author><style face="normal" font="default" size="100%">Uffe N. Nielsen</style></author><author><style face="normal" font="default" size="100%">Ross A. Virginia</style></author><author><style face="normal" font="default" size="100%">Diana H. Wall</style></author><author><style face="normal" font="default" size="100%">Kathleen A. Welch</style></author><author><style face="normal" font="default" size="100%">Diane M. McKnight</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The hydroecology of an ephemeral wetland in the McMurdo Dry Valleys, Antarctica</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Geophysical Research: Biogeosciences</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Antarctica</style></keyword><keyword><style  face="normal" font="default" size="100%">desert hydrology</style></keyword><keyword><style  face="normal" font="default" size="100%">diatom biodiversity</style></keyword><keyword><style  face="normal" font="default" size="100%">hyporheic interactions</style></keyword><keyword><style  face="normal" font="default" size="100%">wetlands</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2019</style></year><pub-dates><date><style  face="normal" font="default" size="100%">11/2019</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019JG005153</style></url></web-urls></urls><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The McMurdo Dry Valleys (MDV) is a polar desert on the coast of East Antarctica where ephemeral wetlands become hydrologically active during warm and sunny summers when sub‐surface flows are generated from melting snowfields. To understand the structure and function of polar wetland ecosystems, we investigated the hydroecology of one such wetland, the Wormherder Creek wetland, during the warm and sunny summer of 2008 &amp;ndash; 2009, when the wetland was hydrologically reactivated. Conservative tracer (LiCl) was injected for a 2‐hour period into a stream above the wetland to determine flow path orientations and hydrologic residence times. Tracer results indicated that surface water is rapidly exchanged with wetland groundwater and wetland residence times may exceed two austral summers. Major ion concentrations were uniform in samples from surface water and shallow groundwater throughout the wetland. Microbial mats in the wetland had high autotrophic index values (the ratios of chlorophyll a [Chl‐a]/ash‐free dry mass [AFDM]), ranging from 9‐38 μg Chl‐a/mg AFDM, indicative of actively photosynthesizing mat communities. The diatom communities in the mats were relatively uniform compared to those in mats from regularly flowing MDV streams, with four endemic and one widespread diatom taxa of the genus &lt;em&gt;Luticola&lt;/em&gt; accounting for an average of 86% of the community. These results indicate that the hydrologic characteristics of the wetland contribute to uniform geochemical conditions. In turn, uniform geochemical conditions may explain the high autotrophic index values of the microbial mats and relatively low spatial variation of the diatom community.&lt;/p&gt;</style></abstract></record></records></xml>