Development of a Simulation Model for Oscillations in Microbial Populations and Greenhouse Gas Emissions after Soil Disturbance
09 / 2008 - unknown
The goal of this project is to investigate greenhouse gas (GHG) emissions and C and N sequestration in agricultural and semi-natural soils after disturbances as regulated by soil microbial dynamics. Specific objectives are: 1) to simulate oscillations in microbial trophic groups and GHG emissions after disturbance in soils differing in management; 2) to carry out a sensitivity analysis of factors affecting microbial oscillations and GHG emissions using the simulation model; 3) to scale up the simulation model by integrating it in a farm-level carbon- and nitrogen-cycling model.
In a current NWO-Russia project (until May 2008), daily dynamics of bacterial counts, soluble soil organic C and mineral N, microbial biomass, and GHG emission have been traced for three weeks in field and laboratory experiments in natural, organic and conventional soils with and without disturbance by simulated rainfall and addition of crop residues or composted manure. These data will be used by Dr. Zelenev for updating and validation of the model BACWAVE-WEB for simulation of wavelike responses of aerobic microbial communities after soil disturbance (Zelenev et al., 2006). The model will be expanded with soil porosity, diffusion of various gases, denitrification, methane production and consumption, and C and N sequestration. Next, the model will be scaled up from field to farm scale, so that predictions can be made about effects of land management on GHG emissions after disturbances.