Determine Benefits of 4R Nutrient Management and Conservation Practices On Water Quality and Use Efficiency via the Arkansas Discovery Farm Program: A Collective Learning Experience

Crops: Cotton Rice
4R Practices: Source Rate Time Place

Lead Researcher:

Dr. Andrew Sharpley

Distinguished Professor of Soils and Water Quality

University of Arkansas

Start Date: 2019

End Date: 2023

Collaborating scientists and universities

  • Dr. Mike Daniels, Cooperative Extension Service, University of Arkansas
  • Dr. Karl VanDevender, Cooperative Extension Service, University of Arkansas
  • Dr. Bill Robertson, Cooperative Extension Service, University of Arkansas
  • Dr. Nathan Slaton, Director Soil Testing Laboratory, University of Arkansas
  • Dr. Trenton Roberts, Crop, Soil and Environmental Sciences, University of Arkansas
  • Larry Berry, Discovery Farms Field Manager, University of Arkansas

Project Summary

Agriculture is the single largest economic sector in Arkansas, accounting for $21.4 billion of value added to the State’s economy in 2016 (University of Arkansas Division of Agriculture, 2019). Arkansas is the nation’s leading rice producer, second in poultry production and in the top 15 among states for cotton, soybean, and corn. Agricultural enterprise account for about 98% of the 1.1 million tons of fertilizer sold annually in Arkansas.

Nutrient enrichment remains a major impairment to the designated uses of fresh and coastal waters of the United States. While there are many sources of nutrients, the contribution of agriculture has received increased attention to reduce nutrient losses, fueled by recent modeling efforts and surveys, which suggest agriculture contributes up to 85% of the nutrients entering the Gulf of Mexico. However, there have been few farm-scale studies of the effects of nutrient management and conservation practice (CP) adoption on water use-efficiency, quality, and system sustainability under cotton and rice production in the Basin, particularly the Lower Mississippi River Basin. These concerns are manifested from regional issues such as hypoxia in the Gulf of Mexico and critical groundwater decline in lower Mississippi Alluvial Aquifer. Also, the cotton supply chain from field to gin, to mill, to retailer, wants assurances that cotton production is sustainable for future business interests. This has prompted supply chain groups such as Field to Market and the Cotton Leeds program, to measure and document indicators of sustainability. Several AR cotton producers are working with the University of Arkansas Division of Agriculture to use the Field Print Calculator for individual fields in AR. The Field to Market Field Print Calculator now includes metrics for rice and is being used by groups, such as the USA Rice Federation, to encourage producers to move towards more sustainable practices.

Project Goals:

  • This project will leverage and modify existing ADF monitoring to determine water quality and use benefits of 4R nutrient stewardship on three ADFs.
  • Collect and compile farm-nutrient management information and data for N, P, and K, along with other soil properties influencing soil fertility, such as pH, CEC, particle-size distribution, organic C, and the suite of Mehlich-3 extractable soil nutrients.
  • Collect soil and water samples, analyze, interpret, verify, and document nutrient and sediment loss reduction and water conservation.
  • Determine if the Field Print Calculator reliably expresses 4R effects plus conservation practices (CPs) on nutrient runoff potential.
  • Deliver an outreach and farmer – collective learning program that disseminates information to all stakeholders.