长三角地区麻栎林生长季小气候调节效应研究

为了揭示长三角地区不同下垫面水热时空变化和小气候特征动态变化的规律，以南京铜山林场麻栎林为对象，采用气候定位对比观测法，研究2012年5-9月林内外土壤温湿度、气温和大气相对湿度等小气候因子的变化特征。结果表明，麻栎林生长季对小气候要素有显著的调节作用。土壤温度随深度增加而降低，深层土日变化波动幅度较小，但表层土温度随时间呈余弦曲线变化。当土层深度>20 cm时，林内土壤温度日较差逐渐接近于0，裸地大约在30 cm处。6、7月林内土壤湿度随土层变化趋势基本一致，先上升后下降。7月林内与裸地气温均值相差最大为1.05℃。林内和裸地的月均大气相对湿度在6-9月差异性较大，最大差异值出现在7月为4.16%，6月和9月次之，8月差异性最小。林内气温月均值和月较差均<裸地。林内外太阳辐射强度日变化均呈现先增加后减弱的趋势，且林内波动幅度<裸地。

Microclimate Regulating Effect of Quercus acutissima Forest in the Yangtze River Delta during Growing Season

In order to reveal the temporal and spatial hydrothermal variations of different underlying surfaces and the dynamic changes of microclimate characteristics in the Yangtze River Delta region,the micrometeorological observation was conducted from May 2012 to September 2012 on the daily and monthly changes of microclimate factors such as temperature and relative humidity in Quercus acutissima stand and its adjacent open sites in Tongshan Forest Farm of Nanjing.The results showed that Q.acutissima had a significant regulating effect on microclimate elements during the growing season.The temperature of soil decreased with depth,which did not display significant fluctuation in the deep soil layer,but changed with time as a cosine curve at surface layer.When the soil depth was greater than 20 cm,the daily range of soil temperature in the forest gradually tended to be 0,and the bare land was about 30 cm.The soil moisture in the forest was basically the same as that in the soil layer,rising firstly and then decreasing with the soil depth in June and July.The difference of average temperature between the forest and bare land was 1.05℃ in July.The monthly average atmospheric relative humidity in the forest and bare land varied greatly from June to September.The maximum difference value was 4.16% in July,followed by June and September,and the smallest difference was in August.The monthly mean temperature and monthly difference in forest were less than bare land.The daily changes of solar radiation intensity in the forest and bare land showed a trend of increasing first and then weakening.The fluctuation value of solar radiation intensity in the forest over time was less than that of bare land.