Cynthia Kallenbach

MSc 2007, International Agricultural Development, University of California Davis

MSc 2008, Soil Biogeochemistry, University of California Davis

PhD 2015, Earth and Environmental Sciences, University of New Hampshire

My research program centers on soil organic matter dynamics in managed and natural ecosystems. Our group investigates how environmental change and land use shape soil microbial communities and organic matter pools, with consequences for carbon and nutrient cycles.

A number of our current projects examine how variable soil moisture, particularly intermittent flooding due to altered precipitation regimes or permafrost thaw, affects critical soil processes regulating soil organic matter-microbial community interactions. I am also interested in whether and how ecosystem properties, like crop diversity, biological legacies, and soil structure, mitigate these effects of variable moisture on microbial function and the fate of soil carbon. Our research integrates field studies with controlled greenhouse and laboratory experiments, using a variety of tools to probe microbial-biogeochemical interactions, including isotopes, microbial functional assays, and biological and chemical molecular techniques.

APBI 412 - Belowground Ecosystems

HP Lieberman, C von Sperber, CM Kallenbach. 2025. Soil phosphorus dynamics are an overlooked but dominant control on mineral‐associated organic matter. Global Change Biology 31 (7), e70307

CCA Horsch, PM Antunes, C Fahey, AS Grandy, CM Kallenbach. 2023. Trait-based assembly of arbuscular mycorrhizal fungal communities determines soil carbon formation and retention. New Phytologist. 239:311–324.

CM Kallenbach, MD Wallenstein, ME Schipanski, AS Grandy. 2019.Managing agroecosystems for soil microbial carbon use efficiency: ecological unknowns, potential outcomes, and a path forward. Frontiers Microbiology 10:1146

CM Kallenbach, AS Grandy, SD Frey, AF Diefendorf. 2015. Microbial physiology and necromass regulate agricultural soil carbon accumulation. Soil Biology and Biochemistry 91:279–290.

USDA-NIFA Postdoctoral Fellowship

USDA-NIFA Pre-Doctoral Fellowship

Young Investigator's Award Soil Organic Matter Workshop

Soil Science Society of America Francis and Evelyn Clark Soil Biology Fellowship