城市植物群落的减噪效果分析

在上海市区选取23个有代表性的城市植物群落进行减噪效益的测定。结果表明，植物群落对噪声的减弱效果和群落的结构组成有关。针叶树林和常绿阔叶树林的减噪效果最好，噪声衰减值均大于10dB；植物群落对噪声的减弱效果明显优于空旷地；建群种相同、林下层次多、植物种类丰富的群落对噪声的衰减效果优于林下无植被的群落；以落叶植物为优势种的群落在生长期对噪声的衰减值比落叶期高4～5dB。

Analysis on noise reduction effect of urban plant community

The noise reduction effects of selected twenty-three representative plant communities were measured and analyzed. The results showed that noise reduction effects of plant community were related to its structure. Coniferous forest and evergreen broad-leaved forest had the best reduction effects and their noise attenuation values were also more 10dB. The effect of noise reduction of plant community was more distinct than that of open space. The plant communities possessing same edificatos, more stories under forest and richer species had better reduction effects than that without any vegetation under forest. The value of noise attenuation of plant community was 4 -5 dB bigger in growing period than in defoliating period.