Integrated water quality and microplastic pollution assessment in urban freshwater systems using statistical and geospatial approaches

Abstract

Rapid urbanization, increasing wastewater discharge, and land-use transformation have significantly degraded freshwater ecosystems, particularly urban rivers and wetlands that continuously receive untreated sewage, stormwater runoff, industrial effluents, and solid waste. In recent years, emerging contaminants such as microplastics have become an additional environmental concern because of their persistence, transport behavior, and ecological risks. The present study focuses on the integrated assessment of physicochemical pollution, heavy metals, microplastic contamination, and landscape-level influences in the Kahn River and Sirpur Wetland, Indore, India. The study was conducted through systematic field investigations, laboratory analyses, statistical evaluation, and geospatial assessment. Water samples were collected from multiple locations along the Kahn River and Sirpur Wetland to evaluate physicochemical parameters, nutrients, and heavy metals using standard APHA methods and instrumental techniques, including ICP-OES and AAS. Microplastics were extracted, quantified, and characterized using stereomicroscopy, FESEM, and ATR-FTIR analysis. In addition, Entropy Weighted Water Quality Index (EWQI), multivariate statistical analysis, and GIS-based Land Use Land Cover (LULC) assessment were performed to examine pollution behavior and the influence of surrounding landscape characteristics on water quality and microplastic distribution.