校园绿地植被结构与温湿效应的关系

Relationship between campus green space vegetation structure and temperature-humidity effect

为了探究小尺度空间下植被结构与小气候之间的关系,选取西安建筑科技大学雁塔校区内5处典型的校园绿地为研究样本,在夏季利用便携式自动气象站对离地1.5m高度的空气温度、相对湿度、太阳辐射强度的日变化进行测定,为优化校园绿地的植物空间配置提供依据.结果表明,不同植被结构的降温增湿作用差别较大,平均降温0.2~2.3℃,平均增湿1.8%~6.5%,总体趋势表现为:人工乔木―自然演替地被>人工乔木―人工灌木―人工地被>人工灌木―人工地被>自然演替地被>人工地被,即绿量越大、乔木层郁闭度越高的复层结构绿地的降温增湿效应越显著.建议采用近自然式种植设计方式进行校园绿地建设,在提升绿量的同时,更侧重植被结构的优化,提升校园绿地的生态效应.

To investigate the relationship between vegetation structure and microclimate in the small-scale space,on the Yanta campus of Xi′an University of Architecture & Technology,the five typical campus green spaces were selected as research samples.The microclimate data were measured with portable automatic weather station.The research measured the solar radiation,relative humidity and air temperature in five sites with 1.5 mheight from the ground,to provide the theoretical basis for the planting design of campus green space.The results showed that the cooling and humidifying effects of different vegetation structure sites varied greatly,the average temperature reduction was 0.2~2.3℃,the average humidifying increase was 1.8% ~6.5%.The humidifying and cooling effect of the different plant communities from high to low were:artificial arbor-natural succession ground cover>artificial arbor-artificial shrub-artificial ground cover> artificial shrub-artificial ground cover> natural succession ground cover> artificial ground cover.That is,the greater amount and higher tree canopy layer of green space,the effect of vegetation structure of campus green space could be more efficient.It is recommended to use the near natural formula planting design approach in constructing the campus green space.We should focus on optimizing the structure of green vegetation rather than increasing the amount of green area,so as to promote the ecological effect of the campus green space.