The effect of tree covers on reducing noise pollution load in Saravan Forest Park, Guilan Province, Iran

This study was carried out in the Saravan Forest Park in north of Iran. The sound level measurements were performed at 12 stations and at distances of 3, 100, 200, 400 and 1000 m from the sound source with three replicates, in the summer and in traffic hours from 10 AM to 2 PM an area without tree cover was selected as the control station. The results indicated that sound intensity at first distance (3 m) with the mean of 77.81 decibel (dB) exceeds the national standard of Iran. In this study, the first significant decrease in the sound intensity was obtained at a distance of 100 m, with the highest reduction of 26 dB for station 10, while the lowest decrease was found at station 11 with 8 dB. In an overall summary, distances less than 200 m are not suitable for tourism accommodation. The average sound intensity at distances in comparison with the permissible value indicate that the park does not currently have any noise pollution at more than 200 m in summer.