2022 | An Agro-Economic Model for Precision Water and Nutrient Management Practices

FACULTY SEED GRANT | Global Change Center

Integrated Agro-economic Modeling to Assess Farmer Uptake of Precision Water and Nutrient Management in a Changing Climate  

INVESTIGATORS:

• Dr. Julie Shortridge,  Biological Systems Engineering
• Dr. Ryan Stewart, School of Plant and Environmental Sciences
• Dr. Wei Zhang, Agricultural and Applied Economics

This study is funded jointly by the Global Change Center at Virginia Tech and the Institute for Society, Culture and Environment (ISCE).

Runoff of agricultural chemicals, including nitrogen (N) and other nutrients, is harmful to water quality as well as farm profitability because growers have to spend more on fertilizer that does not benefit crop growth. Climate change is expected to worsen this problem in the Eastern U.S., as more frequent heavy rainfall (Lall et al. 2018) and increasingly variable rainfall timing (Shortridge 2019) result in greater pollution mobilization and depressed agricultural production. Precision water and nutrient management (PWNM), which optimizes the timing and amount of nutrient and water applications to maximize water and nutrients taken up by the plant, presents a potential “win-win” approach that can reduce agricultural non-point source pollution while also increasing farm profitability (Zurweller et al. 2019; Li et al. 2021). However, PWNM technologies often involve a high upfront cost and annualized benefits that can vary significantly from year to year based on weather conditions, fertilizer costs, and crop prices (USDA 2018). Grower uptake of PWNM has therefore remained stagnant due to perceptions that it is not financially beneficial (Lowenberg-DeBoer and Erickson 2019). There is a critical need for research that can quantify the economic benefits of PWNM across standard technological lifespans (10-15 years) to address barriers to grower adoption.

The objective of this project is to develop an integrated agro-economic simulation model of PWNM adoption using corn production in coastal Virginia as an initial case study. This work will test two hypotheses:

1)  Relative to conventional water and nutrient management (CWNM), the yield and nitrogen uptake benefits of PWNM are greatest in years with highly variable rainfall (heavy rainfall interspersed with long dry periods).

2)  PWNM is more likely to be adopted when interannual yield variation is larger and when forecasted prices of crop and fertilizers are higher.

Reference citations for project proposal description available upon request.