Runoff, erosion, and nutrient transport arising from furrow irrigation in a corn conservation production system

Abstract

AbstractContemporary row‐crop practices in the mid‐southern United States contribute to declining water tables and impairment of downstream waters, threatening the sustainability of irrigated agriculture and vital ecosystem services. This research was conducted to determine whether agro‐hydrology can be altered by cover crop or traffic pattern. The effects of cover crop {Austrian winter pea [Pisum sativum var. arvense (L.) Poiret], crimson clover [Trifolium incarnatum L.], cereal rye [Secale cereal L.], and tillage radish [Raphanus sativus L.]} and traffic pattern (traffic, nontraffic) on runoff, erosion, and nutrient transport from a furrow irrigation event were investigated at Stoneville, MS on a Commerce very fine sandy loam (a fine‐silty, mixed, superactive, nonacid, thermic Fluvaquentic Endoaquept). Relative to winter fallow, the inclusion of a cover crop reduced erosion by at least 16% but had no effect on runoff or the transport of total P, total Kjeldahl nitrogen (TKN), soluble reactive phosphate (SRP), NH4–N, or NO3–N. Eliminating traffic in furrows reduced runoff, erosion, and SRP transport up to 13%. Traffic pattern had no effect on the transport of total P, TKN, NH4–N, or NO3–N. Regardless of treatment, total N loss never exceeded 0.2% of N applied as inorganic fertilizer. This research demonstrates that cover crop and equipment traffic pattern can be manipulated in reduced tillage systems to improve the sustainability of irrigated agriculture and ecosystem services in the mid‐southern United States.