Spatial controls over decomposition of soil organic matter

Soil microbes need to be in close proximity to their substrate to be able to efficiently decompose it. Soil organic carbon content could be a proxy for the average distance between microbes and their substrate in soil. Soil carbon content is thus an potentially important, but often overlooked control over soil organic matter decomposition. With decreasing organic matter content in soils, the probability that a microbe meets its substrate decreases which might have consequences for carbon loss dynamics and microbial strategies to decompose organic matter. In this laboratory incubation experiment at the Grandy lab at the University of New Hampshire, I investigated the effect of spatial separation of microbes and substrate, as a function of organic matter content on microbial strategy for decomposition and decomposition itself. The findings of this project have implications for our understanding of decomposition dynamics in different soil horizons, soil C modelling and management practices for C sequestration.

Collaborators:

A. Stuart Grandy, University of New Hampshire