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根据在鼎湖山季风常绿阔叶林集水区3年的观测结果，对这一南亚热带地带性植被的水文功能进行了较深入的探讨。由于林分结构复杂，季风常绿阔叶林对大气降水具有较高的林冠截留率，截留率的季节变化动态与降水量的季节分配有关。该森林土壤结构良好，其渗水速度快，加上有较厚的枯落物层，对于减缓地面径流，减少水土流失，功效甚大。但由于土层较薄，其蓄水功能有限。该森林的径流量占总降水量的比例特别是地表径流所占比例较小，分别为50．22％和14．19％。其季节分配有利于保持水土和植物生长。由于土壤蓄水量变化出现负值，用水量平衡法计算得出鼎湖山季风常绿阔叶林年蒸发散量为1323．98mm，占大气降水量的51．81％。该森林的降水中主要营养元素浓度较高，降水带来大量的养分，特别是氮素的年输入量高达35．29kg·hm-2。淋溶也给该森林带来较高的养分归还量，其中钾的淋溶量高达35．65kg·hm-2；镁的淋溶量高达8．9kg·hm-2，为林外雨输入的2．37倍。径流中的氮输出为28．35kg·hm－2，降水中的氮素净输入量为6．94kg·hm-2；但镁的净输入呈负值。
Based on the observation results of the monsoon evergreen broad-leaved forest catchment in Dinghu Mountain for three years, the hydrological function of this subtropical zonal vegetation has been discussed in depth. Due to the complex stand structure, the monsoon evergreen broad-leaved forest has a higher canopy interception rate for atmospheric precipitation. The seasonal variation of the interception rate is related to the seasonal distribution of precipitation. The forest soil structure is good, its seepage speed, coupled with a thick layer of litter, to slow down the runoff and reduce soil erosion, great effect. However, due to the thin soil, its water storage function is limited. The ratio of runoff to total precipitation, especially surface runoff, is relatively small, accounting for 50.22% and 14.19% respectively. Its seasonal distribution helps maintain soil and water and plant growth. Due to the negative value of soil water storage, the annual evapotranspiration of the monsoon evergreen broad-leaved forest at Dinghushan was 1323.98 mm, accounting for 51.81% of the total precipitation. The main nutrients in the forest precipitation are high, and precipitation brings a lot of nutrients, especially the annual input of nitrogen reaches 35.29kg · hm-2. Leaching also brought a higher nutrient return to the forest, in which potassium leached up to 35.65kg · hm-2; magnesium leached up to 8.9kg · hm-2 2.37 times. The nitrogen output of runoff was 28.35kg · hm-2, and the net input of nitrogen in precipitation was 6.94kg · hm-2. However, the net input of magnesium was negative.