Karst Rice–Tomato Cascade System: A Sustainable Agricultural Strategy for Groundwater Protection

Karst Rice–Tomato Cascade System: A Sustainable Agricultural Strategy for Groundwater Protection | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Karst Rice–Tomato Cascade System: A Sustainable Agricultural Strategy for Groundwater Protection Yi Zhou, Ying Li, Anqi Wang, Fengling Gan, Youjin Yan, Shaopan Xia, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7845171/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Karst aquifers, despite their importance as drinking water sources, are highly susceptible to contamination due to rapid surface-groundwater interactions. This study investigates how crop spatial zoning—specifically planting rice in upper elevations and tomatoes in lower elevations—acts as a Best Management Practice (BMP) to enhance groundwater quality in the Chenqi karst watershed, Guizhou Province, China. Over a 7-year period (2016–2022), 19 water quality parameters were monitored at five hydro-logical sites, including wells located in distinct cropping zones. Results revealed that groundwater in the downstream tomato field exhibited significantly higher Water Quality Index (WQI) values (up to 72.2) compared to both upstream rice paddies and outlet sites, suggesting that the rice-tomato zoning strategy supports nutrient attenuation and pollutant buffering. Although effluent water quality at the outlet remained de-graded, likely due to non-agricultural inputs, our findings provide empirical evidence that crop zoning based on elevation and hydrology can effectively mitigate diffuse pollution in karst systems. This research contributes to the development of BMP frameworks tailored for karst agroecosystems. Agronomy Agricultural Engineering Water Quality Index (WQI) Surface–groundwater interaction Agricultural runoff Guizhou Province Temporal variation Principal component analysis Best Management Practice (BMP) Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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