Evaluating Spatiotemporal Impacts of Urban Growth on Hydrochemical Dynamics in the Zahedan Aquifer, Iran

Evaluating Spatiotemporal Impacts of Urban Growth on Hydrochemical Dynamics in the Zahedan Aquifer, Iran | 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 Evaluating Spatiotemporal Impacts of Urban Growth on Hydrochemical Dynamics in the Zahedan Aquifer, Iran Hamidoddin Yousefi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6666674/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 The Zahedan aquifer, a vital water resource in southeastern Iran’s arid region, is experiencing significant quality deterioration due to combined anthropogenic and geogenic pressures. This study presents a comprehensive spatiotemporal analysis of groundwater hydrochemistry across the aquifer system, employing year-long monitoring data to quantify urbanization impacts. Results reveal severe contamination gradients, with electrical conductivity (EC) increasing from 2,000 µS/cm in eastern regions to 8,500 µS/cm in western zones, paralleled by chloride concentrations rising from 500 to 3,500 mg/L. Spatial analysis identifies the urban northern and eastern sectors as contamination hotspots, where high-density well extraction for municipal, industrial, and agricultural use interacts with inadequate wastewater infrastructure. Seasonal variations demonstrate temporary water quality improvement during precipitation events, though parameters consistently exceed potable and irrigation thresholds without treatment. Three primary contamination mechanisms are characterized:(i) Anthropogenic wastewater infiltration through urban aquifers (ii) Mobilization of geogenic salinity from detrital formations (iii) Hydraulic gradient alterations from over-extraction. The findings provide critical insights for sustainable groundwater management in semi-arid urban environments, emphasizing the need for targeted infrastructure upgrades, extraction zoning, and nature-based remediation strategies to mitigate compounding salinity sources. Aquifer salinization Urbanization impacts Hydrochemical analysis Groundwater contamination Zahedan aquifer Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Full Text Additional Declarations The authors declare no competing interests. Tables 1 and 2 are available in the Supplementary Files section. Supplementary Files Table1.jpg Table2.jpg Table 2 presents electrical conductivity (EC) measurements collected from 25 monitoring wells during October 6-16, 2016.. 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6666674","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":456714909,"identity":"327dbbae-658d-4573-b38c-3877504d7207","order_by":0,"name":"Hamidoddin 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