Grant Applications Summaries

Nutrient Dynamics in a Sustainable Animal - based Agricultural System

Investigators: J. Capece, K. Campbell, D. Graetz, T. Bancroft, N. Aumen, J. Holt, and M. Mozaffari

Submitted to: NSF-EPA Water and Watersheds Program

University of Florida, the Archbold Biological Station, and the South Florida Water Management District propose a long-term research initiative to study the nutrient dynamics, ecology, hydrology, and socio-economic characteristics of subtropical wet prairie systems subjected to animal-based agriculture. This research is to be conducted at the MacArthur Agro-ecology Research Center on Buck Island Ranch in south-central Florida near Lake Placid. Runoff water from this main cattle production region of Florida drains into environmentally sensitive areas including Lake Okeechobee and the Florida Everglades. Thus, in addition to advancing the sciences of hydrology, wildlife ecology, soil chemistry, and systems modeling, results of this research effort have the potential to significantly affect an important national ecosystem restoration project for the Everglades.

The project elements embodied in this proposal address all three overarching research priorities set by the NSF/EPA Partnership for Environmental Research, with those components being 1) ecological research, 2) hydrologic/biogeochemical research, and 3) social science/economics research. In its original design, the subtropical prairie initiative mirrors these stated priorities. First is a field experiment to study the biogeochemical and hydrologic processes of the prairie system. Second is the measurement of the biological implications of animal-based agriculture on the prairies. Third is the development of component models to represent both the hydrologic/soils processes and the economic implications of land management alternatives. Fourth, is the integration of the component models into a holistic decision support system.

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.


2001 Southern DataStream