Noise Reduction Effect of Four Hedgerows With Different Widths

Taking four kinds of common hedges in Beijing as test materials,the effect of width on noise reduction was studied by using CEL-63xsound level meter,in order to provide reference for the application of hedgerow plants in garden noise reduction.The results showed that,1)hedgerows hadimportant noise reduction function,and width wasthe key factor affecting the noise reduction effect of hedgerows.2)According to the two evaluation quantities of total noise reduction and blank attenuation,the change trend of both with the width wasthe same,showed an increasing trend.Regression analysis showed that the total noise reduction and blank attenuation were logarithmically related to the width,and R2 wasmore than 0.950 0.3)According to the two evaluation quantities of net noise reduction and noise reduction rate,the change trend of them with width wasthe same,and the change in different width ranges was different.In the range of 0-2.0 m,both increased with the increase of width.In this range,the noise reduction effect of Euonymus japonicus and Kerria japonica was better than that of Buxus microphylla and Ligustrum lucidum.In the range of 2.0-4.0m,they gradually decreased with the increase of width,and the downward trend gradually tended to be flat in the range of 4.0-8.0m.4)According to the evaluation quantity of noise reduction ability,with the increase of width,the noise reduction ability of hedgerow gradually decreased and tended to be flat.Regression analysis showed that the noise reduction ability had a logarithmic relationship with the width.R2 was above 0.900 0.In the range of 0-2.0m,the noise reduction ability changed rapidly with the width,and the noise reduction effect was obvious.When the width was ＞4.0m,the noise reduction capacity approachedto 0,and the noise reduction effect was poor.The width of the hedge should be set within 2.0m,and the maximum should not exceed 4.0m.