@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 {1412, title = {Benthic primary production in two perennially ice-covered Antarctic lakes: comparisons of annual accumulation predicted from photosynthesis models with estimates from internal growth markers}, journal = {Antarctic Science}, volume = {13}, year = {2001}, pages = {18-27}, keywords = {LTER-MCM}, author = {Ian Hawes and Daryl L. Moorhead and Sutherland, J and Schmeling, J and Schwartz, A} }