Project Number: 6619-13000-002-00
Project Type: Appropriated

Start Date: Feb 21, 2007
End Date: Feb 20, 2012

Objective:
The long-term objective of this project is to develop an understanding on how integrating the environment, plants, and animal genetic resources will affect sustainability of beef cattle agro-ecosystem while improving the environment and providing water quality protection for the subtropical United States. Over the next 5 years, we will focus on the following objectives: Objective 1: Develop and evaluate environmentally sustainable forage and nutrient management systems that protect and enhance water and soil resources in forage-based beef cattle agro-ecosystems of the subtropics. A. Understand and quantify the impact of grazing cattle, cattle movement, and grazing behavior on changes in water quality and soil nutrients dynamics around and beneath cattle congregation sites (mineral feeders, water troughs, and shades). B. Determine the effect of grazing, stocking rate, and pasture grass-legume mixtures on soil carbon, phosphorus, and nitrogen dynamics, and on above ground net production and N and P uptake in subtropical pastures. C. Assess the ecological and physiological mechanisms of forage plants to cope with wet soils, high water tables, and occasional flooding by forage plants in the subtropics. D. Develop fundamental understanding of the processes controlling nutrient transformations, fluxes, transport, loading, and sequestration following conversion of improved beef cattle pastures to wetland cells. Provide vital information needed to meet water quality goals and standards and quantify effects of BMPs on water quality and for model validations: EAGHM (Everglades Agro-Hydrology Model) and SWAT (Soil and Water Assessment Tool). Objective 2: Assess nutrient richness and degradation of manure pats from ruminants grazing pastures composed partially of tannin containing legumes. A. Determine if natural tannins in temperate and tropical legumes affect C, N, and P mobility, degradation, and cycling from feces. B. Assess microbial activity in dung pats from cattle grazing tannin containing forage plants. Objective 3: Develop and implement technology particularly near-infrared spectroscopy to rapidly assess forage, soil, and manure for chemical nutrients and biological contaminants.

Approach:
The research project outlined in this plan represents the next 5-year component of a long-term research strategy (described below) that optimizes forage-based cow-calf operations while improving sustainability of beef cattle agriculture and water quality protection. This plan seeks to develop and evaluate and environmentally sustainable forage and nutrient management systems that protect and enhance water and soil resources. Through concurrent collaborative studies at three locations representing divergent subtropical soil types, hydrology, and environments, the impact of grazing intensity, cattle movement, and grazing behavior on soil C, P, and N dynamics in pastures will be determined and changes in water quality around and beneath cattle congregation sites will be assessed at the same locations. This plan will also assess nutrient richness and degradation of manure pats from ruminants grazing pastures composed partially of tannin containing legumes. To accomplish this, collaborative studies will determine if natural tannins in temperate and tropical legumes affect C, N, and P mobility, degradation, and cycling from feces. The third component of this project plan is to develop and implement technology, particularly near-infrared spectroscopy, to rapidly assess forage, soil, and manure for chemical nutrients and biological contaminants. This work involves development of new tools and knowledge for scientists, producers, and action agencies so all can better understand the linkages between soil, climate, and farming practices on water quality, leading to the development of appropriate management practices and technologies for water quality protection, pasture stability, and cattle ranching profitability.