红松阔叶混交林不同大小林隙小气候特征

利用HOBO自动气象站对小兴安岭红松阔叶混交林不同大小林隙、郁闭林分和空旷地的小气候因子进行了为期一个生长季的测定.结果表明：红松阔叶混交林林隙与对照样地的光照、地面温度和气温的日变化及其在生长季的变化趋势均呈单峰型曲线.林隙和对照样地空气相对湿度的日变化均为早晨和傍晚较高,正午较低,呈高-低-高的变化趋势；生长季内呈单峰型曲线,其中郁闭林分相对湿度最大,其次为小、中、大3个林隙,空旷地最小.林隙和对照样地降水量及降雨次数随林冠层郁闭程度的增加呈递减趋势，大林隙降雨量约为小林隙的1.4倍.在生长季内,空旷地、大、中和小林隙以及郁闭林分最大风速分别为3.34、2.97、2.87、2.41和1.84 m·s^-1.

Microclimatic characteristics of different size gaps in Pinus koraiensis-dominated broadleaved mixed forests.

By the help of HOBO automatic weather stations, the microclimatic characteristics of different size forest gaps in Pinus koraiensis-dominated broadleaved mixed forests in Xiaoxing’an Mountains were studied during growth season, with closed forest and bare ground as the control. The results showed that the diurnal variation of illumination, ground temperature, and air temperature of the gaps and the controls, as well as the change trend of the microclimatic factors during growth season, all presented a single peak curve. The diurnal variation pattern of relative humidity of the gaps and the control was high-low-high, being higher in early morning and evening and lower at noon. The relative humidity during growth season also presented a single peak curve, and was the highest for closed forest, followed by small, medium, and large forest gaps, and bare ground. The amount and the times of precipitation tended to decrease with increasing forest canopy, and the precipitation amount in large gaps was about 1.4 times as much as that in small gaps. During growth season, the maximum wind speed above bare ground, large, medium, and small gaps, and closed forest was 3.34, 2.97, 2.87, 2.41 and 1.84 m·s^-1, respectively.