The field experiments will seek to measure the effect of cattle stocking rates (cows/acre) on water quality and landscape nutrient cycling. The setting for this study consists of 2 grazing blocks (summer pasture and winter range) with 8 plots in each. The summer pasture plots are 50 acres (400 acres total) while each winter range plots are 80 acres (640 acres total). There will be 4 stocking rate treatments (including a control of zero stocking rate) with 2 replicates of each treatment. Surface water runoff will be measured and sampled at flumes established on each plot (a total of 16 instrument stations). Water quality analysis will focus on establishing nutrient (nitrogen and phosphorus) loading rates for each cattle stocking rate on summer pasture and winter range.
The proposal also seeks support for creation of the computer modeling and economic valuation components of the project. Results from the field experiments will serve as calibration and validation data for a new decision support system (a GIS-based hydrologic simulation model with economic components). In addition, a series of modifications to existing models will be completed under this project: 1) simulation of phosphorus interaction with the soil in adsorption/desorption processes, 2) simulation of phosphorus release from decaying plant material, 3) simulation of the addition of phosphorus by land spreading of manure, and 4) addition of a nitrogen simulation component including transformations, storage and movement with water. The resulting hydrologic model will be integrated with a cow-calf ranching economic valuation model within a geographic information system structure to create a more comprehensive decision support system that will aid in evaluation of land management alternatives for sensitive lands affected by animal-based agriculture.
This application seeks funds to match support provided by the cooperating
organizations. The cooperators are financing creation of a field laboratory
system, initiation of the nutrient cycling field experiments, and development
of innovative modeling approaches to ecosystem processes and management.
The biological monitoring component is funded by the cooperators under
separate contract. Funding for the initial design, construction, and instrumentation
of the experiment is also provided under separate grants and contributions
of the collaborators. NSF/EPA funds are needed to support the various personnel
requirements of the remaining project components. These personnel needs
include field instrument maintenance, data collection, laboratory analyses,
and computer modeling.