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(National Science Foundation OPP#0096250).

The McMurdo LTER Program is a collaborative and interdisciplinary study of the aquatic and terrestrial ecosystems in ice-free regions of Southern Victoria Land, Antarctica. This Polar desert environment offers unique opportunities to examine ecosystems near the physicochemical limits for the assembly of complex biotic communities and provides a model system for detecting and evaluating the effects of climate change on ecosystem processes.

My main focus on this project has been studying organic matter and nutrient cycling. Along with Ross Virginia I have developed techniques for estimating in situ heterotrophic and autotrophic components of the carbon cycle, and mobility of the important nutrient ions ammonium, nitrate and phosphate in Antarctic mineral soils. We are currently developing models to understand controls over the long-term accumulation and turnover of organic matter and nutrient pools using a variety of stable isotopic, kinetic and chemical fractionation procedures.

I am also interested in the relationship between biogeochemistry and soil organisms. In ongoing collaboration with colleagues on the McMurdo LTER (Diana Wall, Ross Virginia, Byron Adams, Michael Poage) project, I am examining the covariance in patterns and scaling of biodiversity and biogeochemistry across major landscapes of the dry valleys (stream and lake margins, ephemeral wetlands, and periglacial features), and using tracer techniques to evaluate the role of soil invertebrates in carbon cycling.

Read more about the McMurdo Dry Valleys LTER program.