RESEARCH INTERESTS
Our research addresses the role of soil microbial communities in controlling ecosystem response to global change. Many ecosystem processes are known to be affected by environmental changes such as changing climate, increasing CO2, and increasing nitrogen deposition. However, very little is known about the ability of microbial communities to adapt to new conditions, and whether different microbial communities may function in different ways. We examine the role of microbial community structure in ecosystem processes using a variety of molecular, microbiological and biogeochemical techniques.
ENZYMES IN THE ENVIRONMENT
Microbes release enzymes into the environment to decompose organic matter so that can assimilate the carbon and nutrients contained in it. Our lab examines the abiotic and biotic controls on enzyme production, turnover, and in-situ activities. For more information please check see our website for the Enzymes in the Environment Research Coordination Network (funded by NSF), directed by Matthew Wallenstein.
ARCTIC AND ALPINE MICROBIAL ECOLOGY
From a human perspective, the cold dark environment of Arctic soils appears like an extreme habitat for life. However, these soils are inhabited by a very diverse group of microorganisms that appear well adapted to this environment. In fact, these microbes remain active below freezing, where they continue to decompose the remnants of plant material that is produced during the short growing season. Our research examines the diversity of life in these soils, to understand WHO they are, WHAT they are doing, and HOW they deal with life in the cold and dark.
Related News Stories:
Links: Toolik Lake LTER, Alaska
Funding: NSF Office of Polar Programs, Colorado Space Grant
SOIL MICROBIAL RESPONSES TO CLIMATE CHANGE
One of the major current challenges for ecologists is to predict how ecosystems will function under the predicted range of future climates. Typically, ecologists extrapolate the relationships of temperature and moisture with the rates of various processes that occur in the soil (e.g. decomposition, N cycling) to estimate the rates of these processes under climate change. This approach assumes that these relationships are constant through time. For this assumption to be true, the microbial communities whose activity drives these soil processes either will not change in response to changing climate, or are functionally redundant. This assumption is in contrast to the generally accepted paradigm that plant, animal, and pathogen communities will shift in community composition and function in response to climate change. Our research examines whether microbial communities acclimate or adapt to changing climate. If they do, do the relationships between abiotic drivers and soil process rates also change?
Related News Stories:
Collaborators: Mark Bradford, Kathleen Treseder, Rich Conant, Eldor Paul, Alan Knapp, John Blair, Elise Pendall, Jack Morgan, Fieke Dijkstra, Jeff Dukes, Steve Allison
Funding: DOE Office of Science, National Institute for Climate Change Research (NICCR), USDA National Research Initiative (NRI), NSF Ecosystems
ENVIRONMENTAL PROTEOMICS AND METABOLOMICS
The field of microbial ecology has benefited greatly from recent technological developments in molecular biology. These genomic tools have allowed us to examine the majority of soil bacteria and fungi that are not easily culturable. While these tools allow us to understand the diversity and community composition of soil microbes, understanding the ecology of these organisms is still a difficult challenge. One promising tool for understanding the physiology and function of complex microbial communities is the emerging field of proteomics. Working with Ken Reardon (CSU-Engineering), We are developing tools to extract and identify proteins from soil communities to better understand microbial responses to stress and global change. We are also using high resolution mass spectrometry to evaluate whether different microbial communities metabolize a common substrate differently.
Funding: NSF Office of Polar Programs, British Ecological Society, NSF Ecosystems
Collaborators: Ken Reardon, Ed Ayers, Heidi Steltzer, Matt Lewis, Ann Hess
CURRENT RESEARCH THEMES
RESTORATION ECOLOGY IN WYOMING COAL BED METHANE FIELDS
We are currently examining the effects of coal bed methane extraction practices on streambed microbial community structure and function in Wyoming. Microbial communities are likely to be sensitive indicators of impacts of human activities on ecosystems, and of ecosystem recovery. We can also guide restoration activities by managing to restore soil function.
Funding: USGS
Collaborators: Geneva Chong, Heidi Steltzer
