城郊不同下垫面对环境温、湿度的影响

城市热场空间分布和动态演变受城市下垫面特征影响较大,基于试验观测数据,对南京大学浦口校区不同景观类型下垫面（林地、草地和裸地）的温、湿度变化规律、特征进行了分析。结果表明：不同下垫面的温度变化趋势相似,温度白天在13：00左右达到最高点,夜间4：00达到最低点;而林地、草地、裸地的湿度变化与温度变化相反,一般在白天13：00左右为最低,而夜间2：00～4：00为最高。白天裸地、草地的温、湿度变化幅度明显大于林地,而在夜间3者非常接近。冬季裸地的地温变化幅度大于草地的地温变化幅度;各深度的地温均为草地高于裸地,并且差异显著。因此草地比裸地具有更强的保温效果。

Dynamics of temperature and humidity at different surface cover land of urban area

In order to identify the spatial distribution of heat and humidity at different urban landscapes and to evaluate their influences on the urban environment quality,the dynamics of temperature and humidity at underlying surface in Pukou campus of Nanjing University were studied based on the field observation.The result showed that air temperature variation patterns in forest,grass land and bared land were similar.Highest and lowest air temperature occurred at 13;00 pm and 4;00 am,respectively.On the contrary,highest and lowest air humidity in the three land covers occurred at 13：00 am and 2 to 4：00 am,respectively.Changes of air temperature and humidity in both bared and grass lands were significantly higher than that in forest at daytime,while changes in the three ones at night were similar.In winter,changes of soil temperature in bared land was higher than that in grass land,and soil temperatures in each depths in grass land were all higher than those in bared land.