Modeling the impact of measured and projected climate and management systems on agricultural fields: surface runoff, soil moisture, and soil erosion

Authors: LEE, SANGHYUN - US Department Of Agriculture (USDA); Moriasi, Daniel; Fortuna, Ann Marie; MIRCHI, ALI - Oklahoma State University; DANANDEH MEHR, ALI - Antalya Bilim University; CHU, MARIA - University Of Illinois; GUZMAN, JORGE - University Of Illinois; Starks, Patrick

Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/3/2024
Publication Date: 5/11/2024
Citation: Lee, S., Moriasi, D.N., Fortuna, A., Mirchi, A., Danandeh Mehr, A., Chu, M.L., Guzman, J.A., Starks, P.J. 2024. Modeling the impact of measured and projected climate and management systems on agricultural fields: surface runoff, soil moisture, and soil erosion. Journal of Environmental Quality. 1-13.

Interpretive Summary: The Long-Term Agroecosystem Research Network (LTAR) was established to develop a national roadmap to enhance or maintain agricultural productivity while achieving desirable environmental goals in the face of a changing and variable climate. This study used computer models to investigate the effect of projected climate on surface water runoff, soil moisture, and soil erosion in the Southern Plains LTAR site for three land use and land management systems: 1) continuous winter wheat under conventional tillage (baseline system), 2) continuous winter wheat under no-till, and 3) cool and warm season forage cover crop mixes under no-till. The results showed that projected climate will lead to low soil moisture for the continuous winter wheat under conventional tillage while soil erosion will still be a concern. However, the no-till winter wheat and no-till cover crops systems significantly reduced surface runoff and soil erosion while conserving soil moisture in soils under the same projected climate conditions. Incorporating cover crops significantly decreased soil erosion (87-91%) while conserving soil moisture for maintaining or increasing crop productivity compared to the baseline land management. These findings may encourage producers implement cover crops and/or no-tillage into their current management systems thereby reducing soil loss, increasing sub-surface soil moisture conditions and, ultimately, contribute to sustainable agriculture in the coming decades under projected climate conditions. USDA is an equal opportunity provider and employer.

Technical Abstract: As global climate change poses a challenge to crop production, it is imperative to prioritize effective adaptation of agricultural systems based on a scientific understanding of likely impacts. In this study, we applied an integrated watershed modeling framework to examine the impacts of projected climate on runoff, soil moisture, and soil erosion under different management systems in the Southern Plains (SP) region, USA. The proposed model uses measured climate data and three downscaled ensembles from the Coupled Model As global climate change poses a challenge to crop production, it is imperative to prioritize effective adaptation of agricultural systems based on a scientific understanding of likely impacts. In this study, we applied an integrated watershed modeling framework to examine the impacts of projected climate on runoff, soil moisture, and soil erosion under different management systems in the Southern Plains (SP) region, USA. The proposed model uses measured climate data and three downscaled ensembles from the Coupled Model Intercomparison Project Phase 6 (CMIP6) at the Water Resources and Erosion (WRE) watershed in SP region to understand the impact of climate change and various climate conditions under three management systems: (1) continuous winter wheat under conventional tillage (baseline system), (2) continuous winter wheat under no-till (WW-NT), and (3) cool and warm season forage cover crop mixes under no-till (CC-NT). The study indicates that the occurrence of agricultural drought is projected to increase while erosion rates will remain unchanged under the baseline system. In contrast, climate simulations imposed on the WW-NT and CC-NT systems significantly reduce runoff and sediment while preserving soil moisture levels. Especially, CC-NT is promising as it could increase productivity. The findings are expected to contribute to a better understanding of the complex responses of hydrologic processes to various climate conditions and agricultural practices, promoting sustainable agriculture in the face of a changing climate. USDA is an equal opportunity provider and employer.