城市绿地降温增湿效应与其结构特征相关性研究

在太原市区选择2类10个不同结构特征的绿地为研究样本,利用HOBO Pro温、湿度数据采集器对绿地水平和垂直方向上温湿度变化进行测定,研究绿地绿量、叶面积指数、绿地面积、周长面积比4个绿地特征要素与绿地降温增湿效应之间的相关性。结果表明,在水平方向上,绿地降温增湿效应与绿地面积、绿量显著正相关,与绿地周长面积比值显著负相关;在垂直方向上,绿地降温增湿效应与绿量显著正相关,降温效应与叶面积指数显著正相关,增湿效应与叶面积指数正相关性不显著。绿地绿量是衡量绿地生态效益的关键因子,应将其作为绿地系统评价体系的一项重要指标。从城市绿地规划与建设的角度看,在增加绿地面积和提高绿量的同时,一方面要重视大面积斑块的绿地,提高其在绿地系统中的比重,另一方面根据绿地用途相应地选择不同的形状,使城市绿化改善城市生态环境的效应得到充分发挥。

Correlation between ecological effect and structure characteristics of urban green areas

This paper focuses on temperature-lowering and humidity-raising effects of open and green areas with regard correlation between ecological effects and structural characteristics of green areas in Taiyuan City.Ten green areas from two different categories were selected as samples.Meteorological data along horizontal and vertical belts of the green areas were synchronously examined by HOBO Pro Temperature/Humidity External Logger.The results show that temperature-lowering and humidity-raising effects are significantly positively correlated with area and green quantity index,but negatively correlated with P/A(perimeter / area) index of open and green areas along horizontal belts.The results also imply that temperature-lowering and humidity-raising effects are significantly positively correlated with green quantity;LAI has a significant impact on temperature-lowering effect,but less impact on humidity-raising effect.Ecological effects of urban green areas are largely dependent on green quantity.This highlights the importance of evaluating green quantity in urban green areas.It emphasizes the importance of increased proportion of large area green patches and green quantity as a means of enlarging green zones.Moreover,it is feasible to adopt green area shapes with different P/A values according to their functions,which effectively improves the benefits of urban green areas.