Abstract
Background: Noise pollution is a major environmental challenge in metropolitan areas. Tehran, with its 14 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 6 of Tehran using GIS technology.
Methods: Noise levels were measured at 170 stations across three time intervals (morning, noon, evening). Key indices (LNP, Leq, TNI, Lmax) were calculated following ISO 1996-2 standards. Spatial analysis and noise mapping were done using ArcGIS 10.1, with land use relationships examined through comparative layer analysis.
Results: The highest noise levels occurred during morning (LNP=89.106 dB, Leq=80.294 dB, TNI=84.965 dB) and evening periods (89.593 dB, 80.464 dB, 86.278 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 15-20% lower noise levels.
Conclusions: 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.