竹类植物夏季微气候特征及其对人体舒适度的影响

Microclimatic Characteristics and Human Comfort Conditions of Bamboo Plant Communities in Summer

增加植被绿化是调节城市微气候和改善城市热岛效应的主要策略之一。然而,对竹类植物群落的微气候特征和热舒适度调节却鲜有研究。以杭州11种常见竹类植物为研究对象,分析了不同竹类植物群落的微气候变化特征,并采用不舒适指数来评价不同竹类植物群落对人体热舒适度的影响。结果显示,不同竹类植物群落与对照点相比,其空气温度、相对湿度以及光照强度存在显著差异。与对照点相比,乔木状竹类植物群落能够降低空气温度1.5~2.6℃,增加相对湿度3.0%~7.9%,遮光率达95.4%~99.9%。不同竹类植物群落与对照点相比,其平均不舒适指数的差异表现为极显著。与对照点相比,乔木状竹类植物不舒适指数降低2.1%~3.5%。通过对微气候因子与竹类植物群落冠层结构特征之间的相关性分析表明,冠层结构特征对植物群落微气候和不舒适指数起着重要的调节作用。本次研究可以提供更多关于竹类植物缓解热岛效应的基础知识,有助于在风景园林规划设计中合理选择竹类植物种类,从而改善城市热环境。

Increasing vegetation is one of the main strategies to regulate urban microclimate and mitigate the urban heat island effect. However, there are few studies on the microclimate and thermal comfort conditions of bamboo plant community. In this paper, 11 species of common bamboo plants in Hangzhou were studied. The variation of microclimate characteristics of different bamboo plant communities was analyzed, and the discomfort index(DI) was introduced to evaluate the effects of different bamboo plant communities on the human body’s comfortable degree. The results showed significant differences in the air temperature, relative humidity and light intensity between the bamboo communities and control site(CK). Compared with the CK, the tree-like bamboo communities decreased air temperatures by 1.5-2.6℃,increased humidity by 3.0%-7.9%, and decreased light intensity by 95.4%-99.9%. The difference in the daily average discomfort index between the bamboo plant communities and CK was very significant. Compared with the CK, the tree-like bamboo plants reduced the discomfort index by 2.1%-3.5%. Correlation analysis between the microclimate factors and indices of the bamboo plant communities’ canopy structural characteristics showed that the canopy characteristics play important regulatory roles in plant community microclimate and DI. The intention of this work is to provide more basic information aid in understanding the role of bamboo plants in the mitigation of the UHI effect, and specifically,to aid in efforts to improve the urban environment through better planning and making the appropriate choice of bamboo plant species used for landscape design.