Document Type : Research Paper
Authors
1
Researcher of Department of Fisheries, Faculty of Natural resources, University of Tehran, Karaj, Alborz, Iran
2
Department of Fisheries, Faculty of Natural resources, University of Tehran, Karaj, Alborz, Iran.
3
Department of Reclamation of Arid & Muntainous Regions, Faculty of Natural Resources, University of Tehran, Karaj, Alborz, Iran
4
Department of Environment, Faculty of Natural Resources, University of Tehran, Karaj, Alborz, Iran
5
Department of Agricultural Extension and Education, School of Agriculture,, Shiraz University, Shiraz, Iran
6
Department of Natural Resources and Environmental Engineering, School of Agriculture, Shiraz University,Shiraz, Iran
Abstract
Maharloo Wetland, a vital yet degraded ecosystem in Iran, faces a dual crisis of severe water scarcity and intense pollution. This study aimed to diagnose the wetland's water quality status to inform a targeted rehabilitation strategy. Seasonal sampling was conducted at 8 stations from autumn 2023 to summer 2024, analyzing physicochemical and microbial parameters and synthesizing data using the Iranian Surface Water Quality Index (IRWQISC). Results revealed a pervasive and critical condition, with IRWQIsc scores (5.2–11.4) categorizing all stations as "very bad" year-round. Spatial analysis identified two consistent pollution hotspots (Stations 7 and 8), located at the inlets of the Soltan-abad and Khoshk rivers respectively. these hotspots exhibited significantly elevated levels of organic matter (BOD up to 450.6 mg/L), nutrients (NO3⁻up to 212 mg/L), and fecal coliforms. These hotspots indicate persistent anthropogenic inputs, likely from agricultural drainage and wastewater. The remaining stations showed relatively better but still poor quality. It is argued that successful rehabilitation requires an integrated two-pillar approach: (1) Immediate, targeted pollution source control at identified hotspots through agricultural best management practices and wastewater regulation, and (2) Scientifically determined ecological water allocation to address the hydrological deficit, informed by methods like flagship species assessment. Allocating water without first mitigating pollution loads would be ecologically inefficient. This spatio-temporal evidence provides a clear roadmap for prioritizing interventions, emphasizing that controlling contamination is the essential prerequisite for any effective hydrological restoration of Maharloo Wetland.
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