@article {4714, title = {Barotropic seiches in a perennially ice-covered lake, East Antarctica}, journal = {Limnology and Oceanography Letters}, volume = {7}, year = {2022}, month = {02/2022}, pages = {26 - 33}, abstract = {

Water movement in ice-covered lakes is known to be driven by wind, sediment heat flux, solar radiation, saline density flows, and advective stream discharge. In large ice-covered lakes, wind-induced oscillations have been found to play a major role in horizontal flows. Here, we report recurrent, wind-driven, barotropic seiches in a small lake with a thick (4 m) permanent ice-cover. Between 2010 and 2016, we recorded 10.5- to 13-min oscillations of the hydrostatic water level in Lake Hoare, McMurdo Dry Valleys, East Antarctica, using pressure transducers moored to the lake bottom and suspended from the ice cover. Theoretical calculations showed a barotropic seiche should have a period of 12.6 min. Barotropic seiches were most frequent during high wind events (\> 5 m s-1) in winter months (February\–November). The period increased during summer months (December\–January) when fast ice thinned and melted along the shoreline.

}, keywords = {LTER-MCM}, issn = {2378-2242}, doi = {10.1002/lol2.10226}, url = {https://aslopubs.onlinelibrary.wiley.com/doi/10.1002/lol2.10226}, author = {Castendyk, Devin and Hilary A. Dugan and Gallagher, Hugh A. and Pujara, Nimish and Peter T. Doran and John C. Priscu and W. Berry Lyons} } @article {4138, title = {Barium and barite dynamics in Antarctic streams}, journal = {Geology}, volume = {46}, year = {2018}, month = {08/2018}, pages = {811 - 814}, abstract = {

Most natural waters are undersaturated with respect to barite (BaSO4), and while much work has focused on the processes of microbially mediated barite precipitation in undersaturated solutions, particularly in marine environments, little documentation exists on the changes in barite saturation in stream waters. We examined ephemeral glacial meltwater streams in the McMurdo Dry Valleys, Antarctica, that undergo large variations in streamflow and temperature on both a diel and seasonal basis. We measured dissolved Ba in stream water in downstream transects and on a diel cycle, total Ba in stream sediments, algal mats, and lake sediments. Ba concentrations decreased downstream in all four transects, and mineral saturation modeling indicates these waters go from supersaturated to undersaturated with respect to barite in very short distances. Ba is concentrated in stream benthic algal mats at a factor less than observed in marine systems. Both seasonal and diel changes in stream water temperature affect the solubility of barite near glacial sources. Our work shows that both changing stream temperature and the presence of algal materials likely play significant roles in controlling Ba concentrations in polar streams.

}, keywords = {LTER-MCM}, issn = {0091-7613}, doi = {10.1130/G45048.1}, url = {https://pubs.geoscienceworld.org/gsa/geology/article/545184/Barium-and-barite-dynamics-in-Antarctic-streams}, author = {Saelens, Elsa D. and Christopher B. Gardner and Kathleen A. Welch and Sue Welch and W. Berry Lyons} } @article {4063, title = {Biogeochemical weathering of soil apatite grains in the McMurdo Dry Valleys, Antarctica}, journal = {Geoderma}, volume = {320}, year = {2018}, month = {01/2018}, pages = {136-145}, abstract = {

The biogeochemical weathering of the mineral apatite links the lithosphere to the biosphere by releasing the essential nutrient phosphorus (P) into the soil ecosystem. In Taylor Valley, Antarctica, faster rates of apatite weathering may be responsible for the higher concentrations of bioavailable soil P that exist in the Fryxell Basin as compared to the Bonney Basin. In this study, we use scanning electron microscopy to quantify the morphology and surface etching of individual apatite grains to determine whether the degree of apatite weathering differs between the Fryxell and Bonney Basins as well as saturated and dry soil sediments. We show that apatite grains from the Fryxell Basin are rounder, have fewer intact crystal faces, and are more chemically etched than grains from the Bonney Basin. In the Bonney Basin, apatite grains from dry soils show few signs of chemical dissolution, suggesting that soil moisture is a stronger control on the rate of apatite weathering in the Bonney Basin than in the Fryxell Basin. In addition, etch-pit morphologies in the Bonney Basin are more clearly controlled by the hexagonal crystal structure of apatite, while in the Fryxell Basin, etch pits demonstrate a wide range of morphologies without clear crystallographic control. Higher rates of apatite weathering in the Fryxell Basin may be due to the legacy of the physical abrasion of apatite grains during transport by a warm-based ice sheet, as well as the higher levels of precipitation and soil moisture closer to the coast. Our grain-scale approach provides a new perspective on P cycling in the McMurdo Dry Valleys and has implications for apatite weathering and P dynamics in the early stages of soil development.

}, keywords = {LTER-MCM}, issn = {00167061}, doi = {10.1016/j.geoderma.2018.01.027}, url = {https://www.sciencedirect.com/science/article/pii/S0016706117320694}, author = {Heindel, Ruth C and W. Berry Lyons and Sue Welch and Spickard, Angela M and Ross A. Virginia} } @article {3203, title = {Boron isotopic geochemistry of the McMurdo Dry Valley lakes, Antarctica}, journal = {Chemical Geology}, volume = {386}, year = {2014}, month = {10/2014}, pages = {152 - 164}, chapter = {152}, abstract = {

The geochemistry of boron was investigated in the ice-covered lakes and glacier meltwater streams within Taylor and Wright Valley of the McMurdo Dry Valleys (MCM), Antarctica, in order to achieve a greater understanding of the source of boron to these aquatic systems and how in-lake processes control boron concentration. Selected lake depths (surface and bottom water) and streams were analyzed for boron geochemistry. Boron stable isotope values in these waters span the range of +\ 12.3\‰ to +\ 51.4\‰, which corresponds to the variations from glacier meltwater streams to the hypolimnion of a highly evaporated hypersaline lake. The data demonstrate that the major sources of B to the aquatic system are via terrestrial chemical weathering of aluminosilicates within the stream channels, and a marine source, either currently being introduced by marine-derived aerosols or in the form of ancient seawater. Lakes Fryxell, Hoare, and upper waters of Lake Joyce, which experience more terrestrial influence of aluminosilicate chemical weathering via glacial meltwater streams, display a mixture of these two major sources, while the source of B in the bottom waters of Lake Joyce appears to be primarily of marine origin. Lakes Bonney and Vanda and the Blood Falls brine have a marine-like source whose δ11B values have become more positive by mineral precipitation and/or adsorption. Don Juan Pond displays a terrestrial aluminosilicate influence of a marine-like source. These hypersaline lake waters from Antarctica are similar in δ11B to other hypersaline lake waters globally, suggesting that similar processes control their B geochemistry.

}, keywords = {LTER-MCM}, issn = {00092541}, doi = {10.1016/j.chemgeo.2014.08.016}, url = {http://linkinghub.elsevier.com/retrieve/pii/S000925411400391Xhttp://api.elsevier.com/content/article/PII:S000925411400391X?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S000925411400391X?httpAccept=text/plain}, author = {Leslie, D.L. and W. Berry Lyons and Warner, Nathaniel and Vengosh, Avner and Olesik, J and Kathleen A. Welch and Deuerling, Kelly} } @article {1150, title = {Biogeochemical weathering under ice: Size matters}, journal = {Global Biogeochemical Cycles}, volume = {24}, year = {2010}, month = {2010}, keywords = {LTER-MCM}, doi = {10.1029/2009GB003688}, author = {Wadham, J. L. and Martyn Tranter and Skidmore, M and Hodson, A. J. and John C. Priscu and W. Berry Lyons and Sharp, M. and Wynn, P. and Margaret S. Jackson} } @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 {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 {1358, title = {Biochemistry of Si in the McMurdo Dry Valley lakes, Antarctica}, journal = {The International Journal of Astrobiology}, volume = {1}, year = {2003}, pages = {737-749}, keywords = {LTER-MCM}, author = {Pugh, H and Kathleen A. Welch and W. Berry Lyons and John C. Priscu and Diane M. McKnight} } @thesis {1386, title = {The biogeochemistry of Si in the McMurdo Dry Valley Lakes}, volume = {B.S.}, year = {2002}, school = {The Ohio State University}, type = {bachelors}, keywords = {LTER-MCM}, doi = {LTER}, author = {Pugh, H} }