7种阔叶植物群落降噪的临界达标宽度

选取南京市部分主干路道路绿地的7种阔叶植物群落,通过沿道路纵向每间隔5m以及不定距移动测量,结果表明:测量时间段内路缘处噪声的等效连续A声级平均值都超出GB3096-2008中相应规定的限制,其中最高的超出6dB,最低的超出1.3dB;同一阔叶植物群落,随着离开路缘的距离增加,降噪效果更加明显;不同的阔叶植物群落在同一距离处的降噪效果不同,这与植物群落的组成和内部结构特征有密切关系;植物群落的降噪效果与林带宽度并非都呈线性关系;7种阔叶植物群落达到声环境功能区环境噪声限值的临界宽度值集中在5～15m范围内;达到一定宽度的阔叶植物群落可以基本满足城市主干路的降噪要求,在道路绿化中可以广泛应用。

Critical Width of Seven Broad-leaved Plant Communities for Noise Reduction to Standard

There were 7 kinds of broad-leaved plant communities of some main roads in Nanjing, and they were chosen as the research object. The noise reduction effect from the plant was measured along the longitudinal road by every 5 m and moving uncertain distance. The result showed that all the average equivalent continuous A-weighted sound pressure levels of the road edge in the measuring time were beyond the limits of the corresponding provisions in GB3096-2008, out of which the highest was beyond 6 dB, the lowest beyond 1.3 dB. As the distance from the road edge increasing, the noise reduction effect of the same broad-leaved plant community was more obvious. The noise reduction effect of different broad-leaved plant communities at the same distance from the sound source were different, that closely related with the composition and the internal structure of those plant communities. Not all the noise reduction effect of plant communities had the linear relationship with the belt width. For the 7 kinds of broad-leaved plant communities, the critical width, at which the noise level reached the ambient noise limits of acoustic environmental functional area, focused on the range of 5 - 15 m. The broad-leaved plant communities in a certain width can basically meet the requirement of the noise reduction, so the broad-leaved plant communities can be widely used in the urban main roads.