Guo Mingchun, Yu Pengtao, Wang Yanhui, Shen Zhenxi, Shi Zhongiie, Du Apeng, He Changqing
Chinese Academy of Forestry, Beijing 100091, China.
Ying Yong Sheng Tai Xue Bao. 2005 Sep;16(9):1633-7.
Canopy interception is an important hydrological process in forest ecosystem, and its modelling is of significance to understand and estimate the rainfall interception by the canopy. In this paper, a canopy rainfall interception model was established by dividing a rain incident into a set of short period, calculating the rainfall distribution intercepted by the canopy, and educing the process of the rain incident. This model considered the effects of the dryness of canopy and trunk on the evaporation from wet canopy and trunk during one rain incident, and introduced two factors, leaf area index (LAI) and surface area of trunk per unit area of ground (SAI), when computing the evaporation. The application of the model to simulate the rainfall interception process in a Larix principis-rupprechtii plantation in Guyuan, south Ningxia Hui autonomous region of China showed that the simulated and measured throughfall were identical, and the absolute deviation between simulated and measured results was within +/- 1 mm. But, when the precipitation was smaller than 6 mm, the simulated throughfall was lower than the measured one. The values of simulated stemflow were lower than the measured values, and the relative deviation between simulated and measured values was smaller when the precipitation was larger. The process of throughfall in the forest was also simulated, with the results fitted well to the measured one.
林冠截留是森林生态系统中一个重要的水文过程，对其进行建模对于理解和估算林冠对降雨的截留具有重要意义。本文通过将降雨事件划分为一系列短时段，计算林冠截留的降雨分布，并推导降雨事件过程，建立了林冠降雨截留模型。该模型考虑了一次降雨事件中林冠和树干干燥程度对湿润林冠和树干蒸发的影响，在计算蒸发量时引入了叶面积指数（LAI）和单位地面面积树干表面积（SAI）两个因子。将该模型应用于中国宁夏回族自治区固原市华北落叶松人工林降雨截留过程的模拟，结果表明，模拟穿透雨与实测穿透雨一致，模拟结果与实测结果的绝对偏差在±1mm以内。但是，当降水量小于6mm时，模拟穿透雨低于实测值。模拟树干茎流值低于实测值，降水量越大，模拟值与实测值的相对偏差越小。同时对森林穿透雨过程进行了模拟，结果与实测结果拟合良好。
