Project Number: 1902-21000-006-00
Project Type: Appropriated

Start Date: Dec 17, 2002
End Date: Dec 16, 2007

Objective:
1. Develop a rational basis for selecting species components of diverse forage plant communities in grazing lands by identifying plant functional groups based on plant physiological and morphological characteristics. 2. Determine how biotic and abiotic stresses individually and collectively affect productivity of diverse forage mixtures, and how biodiversity might mitigate these stresses. 3. Test model assemblages of forage species in grazed pastures to determine how plant diversity in grazing lands affects soil, plant, and livestock productivity. 4. Develop key indicators of plant biodiversity for monitoring the status and condition of grazing lands at landscape and farm scales. 5. Develop sustainable systems for producing biomass feedstock and evaluate the economic and environmental consequences of bioenergy crop production.

Approach:
1. Critical above- and below-ground plant traits related to plant performance in pastures will be examined among cool-season grasses, legumes grown in field plots, greenhouse experiments, and plants grown in solution culture. A combination of principal component, cluster and discriminant function analysis will be used to select the possible numbers of distinguishable functional groups and assign species to functional groups. Productivity of assemblages containing different numbers of functional groups and species will be evaluated with field tests under different Northeast environments. 2. Field research at the plant community scale will determine if pastures composed of complex species mixtures are more productive than simple mixtures under a range of environmental conditions. Mechanisms by which functional group diversity improves pasture productivity will be examined and we will determine the effects of biotic and abiotic stress on genetic diversity within clonal pasture species and develop methodologies to identify plant roots by species. 3. A grazing study will be conducted to measure milk production and forage intake of dairy cattle grazing pastures of different plant diversity. 4. Plant species diversity in grazing land ecosystems will be determined at the landscape and regional scales. We will aggregate our results from plot and paddock-scale research and apply this knowledge at the landscape, farm, and regional scales. 5. Biomass production of perennial grasses will be determined in buffer strips and CRP land. We will conduct multi-location field plot and farm-scale trials to determine the economic and environmental effects of rotations of perennial and annual crops grown for bioenergy.