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Ashley Keiser

I am a Postdoctoral Fellow associated with the Hofmockel lab. I am an ecologist working at the interface of above- and below-ground communities. My interests include ecosystem ecology, biogeochemistry, climate change, and invasive species. Through my research program, I examine local, mechanism-driven questions, which have advanced ecological theory regarding microbial community function, and landscape-level biogeochemical inquiries that relate to land management.

Widder et al., 2013 Fluvial network organization imprints on microbial co-occurrence networks PNAS

Microbial communities orchestrate most biogeochemical processes on Earth. In streams and rivers, surface-attached and matrix-enclosed biofilms dominate microbial life. Despite the relevance of these biofilms for ecosystem processes (e.g., metabolism and nutrient cycling), it remains unclear how features inherent to stream and river networks affect the fundamental organization of biofilm communities in these ecosystems.

Kirsten Hofmockel

Kirsten Hofmockel is an associate professor in the Ecology, Evolution and Organismal Biology Department at Iowa State University.  She directs the Microbial Ecology Laboratory, which focuses on connecting microscale mechanism to ecosystem-scale biogeochemical processes.
[email protected]


Alternative Biomass Cropping Systems & Microbial Processes

A critical gap in making progress toward ecologically beneficial farming practices is an explicit understanding of how soils store carbon (C) and nitrogen (N) over the long term. Farmers are facing new challenges that require management practices for improving soil quality, increasing both belowground (live roots) and aboveground (live cover) biomass, increasing soil organic matter, and reducing greenhouse gas emissions. To identify optimal man¬agement strategies, an understanding of microbial processes that regulate C and N cycling is essential.

Denitrification in prairie potholes

Denitrification is a crucial aspect of the N cycle, transforming terrestrial N into atmospheric N.  While this can reduce eutrophication of aquatic systems, it can also product N2O, a potent greenhouse gas.  At present there is a critical need to understand the underlying microbiology that drives denitrification so land managers can maximize the benefits of denitrification and minimize greenhouse gas emissions. Our research consists of both field measurements and laboratory manipulations aimed at linking microbiology to ecosystem denitrification rates.

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