The Regulatory Effects of Local Microclimate in Urban Wetland——A Case Study of West Lake in Hangzhou,China
ZHANG Wei;ZHU Yu-bi;CHEN Feng;School of Geographical Sciences,Southwest University;School of Economics and Management,Southwest University;Zhejiang Institute of Meteorological Sciences;
Urban wetland has an important function in local microclimate regulation,and plays an important role in many aspects like the mitigation of urban heat islands and the improvement of urban living environment.In a study reported in this paper,we chose the West Lake in Hangzhou as the study area,and discussed the local microclimate regulatory functions of urban wetlands through field observation of several meteorological elements between the West Lake and its adjacent districts in Hangzhou,China.The results showed that compared with the surrounding built-up districts,the West Lake had a remarkable cold island effect,humid island effect and wind island effect,while the rain island effect was not obvious.The changes of wind field in urban wetland areas tended to affect the local temperature and humidity fields,thus enhancing the cold island effect and humid island effect of the urban wetland.The West Lake had an obvious seasonal difference in its microclimate regulatory functions.The order of cold island effect in the four seasons was summer winter autumn spring;the order of humid island effect was winter autumn summer spring;and the order of wind island effect was wintersummerautumnspring.The microclimate regulatory effect of urban wetlands was intense in winter.The West Lake showed an obvious circadian rhythm for its microclimate regulatory function.The cold island effect and humid island effect were weaker during the day than at night;while the wind island effect during the day was stronger than at night.The differences among urban heat island modes caused by different seasons and climate backgrounds may have a great impact on the circadian rhythms of urban wetland's microclimate regulatory function.The precipitation phenomenon significantly affected the intensity and diurnal variations of urban wetland's microclimate regulatory effects.The urban wetland's local microclimate regulatory effects were almost absent in rainy days for all seasons,which indicated the existence of a "rain lag" effect in urban wetland's microclimate regulatory function.
【Fund】： 中央高校基本科研业务费专项资金资助(SWU115003);; 国家自然科学基金项目(41101039)
【CateGory Index】： P463.2
【CateGory Index】： P463.2