SP 13: Microbial biomass and activity

Microbial biomass and activity

Principal investigator(s):

Co-Principal investigator(s):

Phd candidate(s):

Contact adress:

Helmholtz Centre for Environmental Research UFZ Leipzig-Halle, Department of Soil Ecology, Theodor-Lieser-Straße 4, 06120 Halle (Saale), Germany

Summary

Soil microorganisms are important drivers of soil genesis and function, mainly relying on plants to directly or indirectly supply nutrients. The transformation of soil organic matter through microbial decomposition is responsible both for carbon release to the atmosphere and carbon sequestration in soils, which contributes to soil fertility. Tree species diversity and composition influences soil nutrient status in relation to microbial decomposition and carbon cycling, microbial nitrogen cycling, and microbial growth and broad community composition. The goal of subproject 13 is to use the design, sites and experiments of the BEF-China research unit to determine the role of soil microorganisms in the functioning of highly diverse subtropical forests of southern China. A particular focus is on the relationships between plant diversity, soil stabilization, and nutrient cycling. Methodologically, this will be performed using an integrated approach to measure both microbial biomass (PLFA analysis) and several key microbial functions (extra-cellular enzyme activity, gross nitrification and N mineralization, and substrate induced respiration) in order to provide a mechanistic link to a) determine the functional realization of soil microbial genetic diversity, and b) determine the microbial role in soil erosion and decomposition. In this frame we have two major objectives: 1) to determine the role of soil microorganisms in the main experimental plots along a tree diversity gradient of the BEF-China during the early stages of reforestation; 2) Determine the effects of subtropical litter diversity/litter quality on microbial biomass and activity based on a litter decomposition experiment.