Soil health responses of circular grass buffer strips in center‐pivot irrigated agriculture

Abstract

Decline in water table in the Ogallala Aquifer, along with soil degradation, has threatened the sustainability of agriculture in the US High Plains region. Circular grass buffers in center pivot irrigated cropping systems could support sustainable crop production by providing multiple ecosystem services. This study evaluated soil organic matter (SOM), nutrients, and other selected soil health indicators under circular buffer strip grasses (BSG), adjacent buffer strip corn (Zea mays L.) (BSC), and continuous conventional corn (CCC) in the 0-80 cm soil profile. Soil samples were collected from the center of corn and grass strips for 5 years (2017-2021) and analyzed for nitrate N (NO 3 − -N), soil pH, electrical conductivity, cation exchange capacity, SOM, and soil nutrients. The NO 3 − -N under CCC in 0-20 cm (18.4 mg kg −1 ) and 60-80 cm (4.97 mg kg −1 ) were 1.56 and 1.96 times higher than BSC.The NO 3 − -N was significantly lower under BSG than other treatments in 0-20 cm, 20-40, and 40-60 cm depths. The SOM was similar among all treatments. Response of other nutrients varied among treatments and inter-annually. Soil pH in 0-20 cm depth was 0.1 and 0.3 units lower in CCC (pH = 7.7) than in BSC and BSG. Soil electrical conductivity was 37.5% and 25% greater in CCC than BSG (0.24 and 0.24 dS m −1 ) in 0-20 and 20-40 cm depths, respectively. Grass buffer strips maintaining SOM despite no irrigation, less residual N under corn with grass buffer, and less rapid changes in soil pH suggest the potential of grass buffer to maintain soil health in semi-arid cropping systems facing the transition to dryland.

Economics of strip cropping with autonomous machines

“…Depending on the cost of the autonomous tractor and trailed sprayer (or autonomous sprayer unit), the time window for spray applications and other factors, it might be more profitable to use a narrow spray boom (to match strip width) and reduce headland width. Given the added machine traffic on the strip cropping headlands, grass or flower strips would be worth consideration as evidence is available for agronomic, ecological, and economic benefits (Al‐Amin, Dicken et al., 2023; Quinn et al., 2017; Sapkota et al., 2022).…”

Economics of Strip Cropping with Autonomous Machines

“…Depending on the cost of the autonomous tractor and trailed sprayer (or autonomous sprayer unit), the time window for spray applications and other factors, it might be more profitable to use a narrow spray boom (to match strip width) and reduce headland width. Given the added machine traffic on the strip cropping headlands, grass or flower strips would be worth consideration as evidence is available for agronomic, ecological, and economic benefits (Al-Amin, Dicken et al, 2023;Quinn et al, 2017;Sapkota et al, 2022).…”