1a. Objectives (from AD-416):
Identify mechanisms controlling interannual variability in biomass production in diverse and simple grasslands.
1b. Approach (from AD-416):
Establish experimental treatments manipulating the precipitation seasonality and interannual variability in switchgrass monocultures and in mixed-species prairie, and measure responses in above- and below-ground productivity, nitrogen cycling, plant species composition, and plant ecophysiology.
3. Progress Report:
This new cooperative agreement provides funds for the University of Texas to hire a post doctoral research associate to conduct research on interactions between precipitation variability, nitrogen cycling, and ecosystem productivity in diverse and monoculture perennial grass systems in the Long Term Biomass Experiment. A post doc is initiating field research on the effects of precipitation limitation on biomass productivity in diverse perennial grass systems, and has completed and analyzed a greenhouse/laboratory study of controls on early growth in native and introduced grasses. The manuscript is in preparation.