Project Number: 6064-21660-001-35-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Apr 1, 2020
End Date: Mar 31, 2021
1. Determine cost-effective management practices to stabilize or improve dryland soybean yield and economic return in major soil types and growing environments across Mississippi. This research will determine the effectiveness of cover crop during the fallow season, broiler litter, municipal biosolids and biochar for improving soil health and increasing soil water infiltration, soil water holding capacity and organic matter, and minimizing runoff. 2. Apply agroecosystem models, in conjunction with field trials in Objective 1, to determine optimal production/management options for consistent dryland soybean yield across typical Mississippi weather conditions and in each of 16 dominant soil types based on 100-year daily weather records and on predicted daily weather in future 50 years. 3. Conduct economic analysis using results of field trials (Objective 1) and simulation studies (Objective 2) to compare the cost and return of using soil organic amendments or/and cover crop in comparison with conventional management practices. The goal is to help non-irrigated soybean growers in different Mississippi environments determine the long-term profit-maximizing management practices for a soil type, topography, precipitation pattern, and other climate conditions found on their farms.
Field experiments were carried out at Mississippi State University (MSU) experiment stations in Pontotoc and Starkville. Cover crop, poultry litter and commercial fertilizer treatments were evaluated at MSU Pontotoc and Starkville North farm experiment stations. Class A biosolids, flue gas desulfurization (FGD) gypsum, lignite, biochar, poultry litter and farmer standard fertilizer treatments were evaluated at MSU Starkville experiment station where cover crop was evaluated. Research at both locations determine the effect of poultry litter, municipal biosolids, biochar, and cover crop on soybean yield, soil water holding capacity, plant water availability in soil, rain-water use efficiency and soil health. Measurements of soil biological, chemical, physical and hydraulic properties including soil organic matter, water holding capacity, plant available water content, infiltration rate and soil saturated hydraulic conductivity based on geo-referenced soil core samples taken from 0 to 36 inch depth at those study sites. RZWQM2, APEX, DSSAT, SWAT and MODFLOW models will be employed in a complementary manner to evaluate impacts of different scenarios of poultry litter, municipal biosolids, biochar, and/or cover crops on soybean water status, growth and development, grain yield, water consumption and nitrogen use, and soil health. Briefly, these are process-based, daily-time step models designed for characterizing the effects of different management options on crop growth and development, yield, water and nitrogen uptake and balance, soil and water quality, and groundwater level.