中文摘要：

为研究北京山区典型森林植被对降雨再分配过程的影响，通过生态站定位观测林下穿透雨、树干茎流及林外降雨特征和气候因子，分析影响林冠截留量的主要因子间的相关关系，并通过引入郁闭度因子改进林冠截留模型模拟以反映动态条件下林冠截留特征．结果表明，（1）各林分林下穿透降雨、林冠截留量均与林外降雨量存在良好的线性相关关系；（2）林冠截留量与降雨量、30min最大雨强及降雨历时显著相关，而与平均降雨强度、两次降雨间隔、前24h降雨量的相关性不高；（3）阔叶林、针叶林林冠截留率逐渐趋于平稳的降雨量级分别为2．1-5mm和5．1—10mm；（4）引入郁闭度参数的林冠截留半经验模型，较原模型精度有所提高，对北京地区的林冠截留具有较好的模拟效果．

英文摘要：

In order to understand the effects of rainfall redistribution characteristics within typical forest vegetation in Beijing mountain area, gross rainfall, throughfall, stemflow and micrometeorology were recorded through positioning observation at Jiufeng Ecology Station. The relationship between main factors that affects the canopy interception were analyzed and the dynamic canopy interception were simulated by improved canopy intercept with crown density factor. The results showed that ： （ 1 ） Throughfall and canopy interception were both in a good linear correlation with gross rainfall inside;（2 ）Canopy interception and rainfall ,30min maximum rainfall intensity and rainfall duration were highly relevant, while average rainfall intensity, rainfall interval time, 24 hours rainfall were not ; （ 3 ） As canopy interception rate gradually trend steady, the rainfall grade of broad-leaved forest and coniferous was 2. 1-5ram and 5. 1-10ram; （4）The accuracy of canopy interception semi-empirical model introducted with canopy density parameter was higher than the original model ,which proved the model could get better simulation results applying in Beijing area.