DayCent Biofuel Modelling Efforts Bill Parton Steve Del Grosso Steve Ogle
Outline DayCent model description Model Testing –N 2 O –Soil C –Plant production Biofuel validation sites Biofuel model results Conclusion
CH 4 Uptake 0-1 cm 1-4 cm 4-15 cm cm etc. N GAS 0-1 cm 1-4 cm 4-15 cm cm etc. NO cm NH cm 1-4 cm 4-15 cm cm etc. H 2 O soil T soil CO 2 ACTIVE yr SOM SLOW yr PASSIVE yr CO 2 PLANT COMPONENTS LEAVES FINE ROOTS BRANCHES LARGE WOOD LARGE ROOTS DEAD PLANT MATERIAL STRUCTURAL METABOLIC NPP C:N Death N Uptake N inputs C:N Decomp RhRh RhRh N Min S, R h S S S S Decomp PPT, V, L Den Nit Stom ET V S = Soil Type V= Veg Type L = Land Use DAYCENT MODEL Parton, et al Kelly et al Del Grosso et al. 2001
Model Testing Agricultural Experiment Sites –N 2 O –Soil C –Crop yields Agricultural Census
Corn Grain Yields (21 Counties)
Biofuel Model Testing Sites Penn State Biofuel Plots –Corn, soybean, alfalfa, poplar Kellogg Biological Station Biofuel Plots –Poplar Nebraska Biofuel Plots –Switchgrass Data Sets –N 2 O –Soil C and N –Crop yields
Observed and DAYCENT N 2 O for Biofuel Cropping Systems in Pennsylvania
Cropping Systems Switchgrass Reed Canarygrass Corn-Soybean – (CT) Corn-Soybean – (NT) Corn-Soybean – ALFALFA (CT) Corn-Soybean – ALFALFA (NT) Hybrid Poplar
Greenhouse gas sources and sinks from bioenergy cropping systems in the near-term Adler, P.R., S.J. Del Grosso, and W.J. Parton Life cycle assessment of net greenhouse gas flux for bioenergy cropping systems. Ecol. Appl. 17(3):675–691.
Grassland/Degraded Land
Conclusions Extensive data sets exist to test biofuel cropping models –Crop yields –Soil C and N –Trace gas fluxes DayCent model has been tested for biofuel crops –Pennsylvania –Michigan –Nebraska Current land use greatly impacts net greenhouse gas budgets of biofuel crops –CRP and grassland conversions