Spatial-Temporal Analysis of Noise Pollution and Its Relationship with Land Use in Tehran’s District ۶ Using GIS

Introduction: Noise pollution is a major environmental challenge in metropolitan areas. Tehran, with its ۱۴ million population and heavy traffic, suffers from severe noise pollution due to inadequate land use planning and inefficient transportation systems. This study examines the spatiotemporal characteristics of noise pollution and its relationship with land use in District ۶ of Tehran using GIS technology.Methods: Noise levels were measured at ۱۷۰ stations across three time intervals (morning, noon, evening). Key indices (LNP, Leq, TNI, Lmax) were calculated following ISO ۱۹۹۶-۲ standards. Spatial analysis and noise mapping were done using ArcGIS ۱۰.۱, with land use relationships examined through comparative layer analysis.Results: The highest noise levels occurred during morning (LNP = ۸۹.۱۰۶ dB, Leq = ۸۰.۲۹۴ dB, TNI = ۸۴.۹۶۵ dB) and evening periods (۸۹.۵۹۳ dB, ۸۰.۴۶۴ dB, ۸۶.۲۷۸ dB). Spatial analysis identified the eastern sector as the noisiest area, exceeding permissible limits at all measurement points. Strong correlations were observed between noise levels and commercial/residential land uses, while vegetated areas showed noise levels ۱۵–۲۰% lower than non-vegetated areas.Conclusion: This study demonstrates that GIS-based noise mapping effectively identifies critical pollution zones. The findings emphasize the need for land use policy reforms, including traffic management in high-density areas and green space development. The methodology provides a replicable framework for urban noise assessment in similar metropolitan contexts.

Keywords:

Tehran noise pollution , Noise mapping , GIS and spatial analysis , Noise pollution indices (Leq , LNP , TNI)