Spatial Heterogeneity and Ecological Risk Patterns of Wastewater Discharge in a Rapidly Urbanizing Watershed

Spatial Heterogeneity and Ecological Risk Patterns of Wastewater Discharge in a Rapidly Urbanizing Watershed | 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 Article Spatial Heterogeneity and Ecological Risk Patterns of Wastewater Discharge in a Rapidly Urbanizing Watershed Peng Jia, Shihao Cui, Baohong Lu, Yimei Xi, Peiwei Xiao, Hao Lin, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9239101/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Accurately resolving the spatial configuration and pollution-load clustering of fixed wastewater sources is critical for ecological protection in rapidly urbanizing watersheds. However, the spatial heterogeneity of discharge patterns and their interactions with sensitive aquatic systems remain insufficiently understood. Using a 2023 inventory of operational discharge points in Jinjiang City, we integrated Ripley’s K-function, hot spot analysis, and standard deviational ellipse to characterize multi-scale spatial patterns and associated ecological risks. Results show pronounced clustering of point sources in the western and central zones, with four distinct aggregation typologies ranging from strong clustering to quasi-random distributions. Buffer analysis identifies rivers as the dominant receptors within 1,000 m of discharge outlets, implying higher ecological vulnerability relative to reservoirs and lakes. Pollution-load source apportionment based on chemical oxygen demand (COD), ammonia nitrogen (NH₃–N), and total nitrogen further delineates 15 priority industries into three functional archetypes: centralized treatment–dominated, industrial-driven, and composite industrial–livestock forms. Spatially, COD and NH₃–N hotspots co-occur in the southeastern region, whereas cold spots are concentrated in the north. Overall, this study uncovers the complex spatial heterogeneity and key high-risk zones of industrial wastewater emissions, providing an ecological basis for optimizing industrial spatial layout and implementing targeted watershed-scale pollution control strategies. Biological sciences/Ecology Earth and environmental sciences/Ecology Earth and environmental sciences/Environmental sciences Earth and environmental sciences/Hydrology Wastewater discharge Spatial clustering Buffer zone analysis Ripley’s K function Ecological risk Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 12 May, 2026 Reviewers agreed at journal 09 May, 2026 Reviewers invited by journal 07 Apr, 2026 Editor invited by journal 01 Apr, 2026 Editor assigned by journal 28 Mar, 2026 Submission checks completed at journal 28 Mar, 2026 First submitted to journal 26 Mar, 2026 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9239101","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":621686759,"identity":"ecf66200-c9d1-4e26-81c1-696abcb4cd03","order_by":0,"name":"Peng 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clustering, Buffer zone analysis, Ripley’s K function, Ecological risk","lastPublishedDoi":"10.21203/rs.3.rs-9239101/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9239101/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAccurately resolving the spatial configuration and pollution-load clustering of fixed wastewater sources is critical for ecological protection in rapidly urbanizing watersheds. However, the spatial heterogeneity of discharge patterns and their interactions with sensitive aquatic systems remain insufficiently understood. Using a 2023 inventory of operational discharge points in Jinjiang City, we integrated Ripley\u0026rsquo;s K-function, hot spot analysis, and standard deviational ellipse to characterize multi-scale spatial patterns and associated ecological risks. Results show pronounced clustering of point sources in the western and central zones, with four distinct aggregation typologies ranging from strong clustering to quasi-random distributions. Buffer analysis identifies rivers as the dominant receptors within 1,000 m of discharge outlets, implying higher ecological vulnerability relative to reservoirs and lakes. Pollution-load source apportionment based on chemical oxygen demand (COD), ammonia nitrogen (NH₃\u0026ndash;N), and total nitrogen further delineates 15 priority industries into three functional archetypes: centralized treatment\u0026ndash;dominated, industrial-driven, and composite industrial\u0026ndash;livestock forms. Spatially, COD and NH₃\u0026ndash;N hotspots co-occur in the southeastern region, whereas cold spots are concentrated in the north. 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