Location: Southeast Watershed Research
Project Number: 6048-11130-004-00-D
Project Type: In-House Appropriated
Start Date: Jun 14, 2016
End Date: Aug 1, 2019
Objective 1: Quantify reduced soil loss, nutrient, water, and pesticide use efficiencies of best management and conservation practices and devise options for improvements suitable for southeastern cropping systems. Objective 2: Quantify the effects of integrating bioenergy feedstocks into southeastern cropping systems on soil resources and environmental quality and develop options for mitigating adverse effects. Objective 3: Quantify potential benefits and risks of using flue gas desulfurized gypsum with and without broiler litter in southeastern cropping systems to reduce phosphorus loss via runoff.
This project will evaluate soil processes in cropping systems that incorporate biomass crops into traditional annual row crop rotations and that facilitate the conversion of idle and marginal agricultural lands to perennial biomass production systems. Goals will be accomplished through provision of: improved data (C&N accretion and cycling rates, water availability and quality effects, evapotranspiration estimates, yield potential and yield indices) for crop production and watershed model calibration; site-specific C and N cycling and trace gas data for the ARS GRACENet database and the Southern Multistate Research Committee’s project S1048; soil quality and hydraulic data that will aid in the development of conservation practice targeting recommendations for sensitive landscape positions within farms and improve hillslope, small watershed, and riparian model parameterizations for Little River Experimental Watershed (LREW); improved understanding of the relationships between crop water use efficiency, soil characteristics (texture, bulk density, carbon content, soil-water holding capacities), and crop biomass production that will facilitate validation of soil water estimation by satellite; and improved information on the effects of conservation practice, future land use, and environmental change scenarios for the southeastern coastal plain region to integrated National Program Assessments’ “what-if” analyses. Emphasis is placed on studies that: 1) define benefits of combining gypsum with conservation-tillage in row crop production systems; 2) use leguminous cover crops to improve the net energy balance of production systems that include biofuels feedstocks; 3) develop guidelines for appropriate nutrient (poultry manure and inorganic fertilizer nitrogen, phosphorus, and potassium) and water amendment rates for perennial grass feedstock production systems; and 4) determine how agronomic and soil management practices impact the fate and soil persistence of herbicides used for control of glyphosate resistant weeds rapidly spreading through southeastern landscapes.