论文部分内容阅读
Gash解析模型及其修正的模型是估算和预测林冠截留的有效工具,探讨其在南亚热带森林植被冠层截留模拟中的适用性,是认识该区域结构相对复杂的自然林分冠层的降雨截留能力及其相关科学问题的重要基础。基于2009年鼎湖山国家级保护区内季风常绿阔叶林样地降雨及其他气象因子的观测数据,采用修正的Gash模型对南亚热带地带性顶极群落季风常绿阔叶林的冠层截留量及其组分进行了模拟量化。结果表明:2009年,季风常绿阔叶林林内穿透雨量、树干径流量和林冠截留量分别为1310.9、85.5和498.9 mm,分别占林外总降雨量的69.2%、4.5%和26.3%。基于修正的Gash模型对林冠降雨截留量的同期模拟值为473.0 mm,模拟截留量比实测值低25.9 mm,相对误差为5.2%。对干季降雨截留模拟的相对误差较小(1.8%),湿季稍大(6.8%)。从林冠截留量的构成来看,降雨停止后的林冠蒸发(231.4 mm)是林冠截留的主要组成部分,占总截留量的48.9%。整体上,国内基于Gash及其修正模型对森林冠层截留的模拟相对误差在0.2%~35.0%。林冠持水能力被视为模型准确估算林冠截留量的先决条件,国内运用不同方法估算的不同林分林冠持水能力大致处于0.23~2.86 mm。修正的Gash模型适用于南亚热带季风常绿阔叶林林冠截留的模拟应用。
The Gash analytical model and its modified model are effective tools for estimating and predicting canopy interception, and discussing its applicability in the simulation of canopy interception in the subtropical forest vegetation in China. It is to recognize the rainfall interception of natural forest canopy whose structure is relatively complex in this region Ability and its related scientific issues important foundation. Based on the observed data of precipitation and other meteorological factors in the monsoon evergreen broad-leaved forest in Dinghushan National Reserve in 2009, a modified Gash model was used to estimate the canopy interception of the monsoon evergreen broad-leaved forest in the subtropical zonal community Quantities and their components were quantified by simulation. The results showed that in 2009, the amount of throughfall, trunk runoff and canopy interception in the monsoon evergreen broad-leaved forest were 1310.9, 85.5 and 498.9 mm, accounting for 69.2%, 4.5% and 26.3% of the total rainfall outside the forest respectively. Based on the revised Gash model, the simulated rainfall interception of the canopy was 473.0 mm, the simulated interception was 25.9 mm lower than the measured value, and the relative error was 5.2%. The relative error of simulated rainfall interception in dry season is small (1.8%) and slightly larger in wet season (6.8%). From the perspective of the composition of canopy interception, the canopy evaporation (231.4 mm) after rainfall stopped was the main component of canopy interception, accounting for 48.9% of the total interception. On the whole, the relative error of simulation of forest canopy interception in China based on Gash and its modified model is between 0.2% and 35.0%. Canopy water holding capacity is regarded as a prerequisite for accurate estimation of canopy interception. The water holding capacity of different canopy forests estimated by different methods in China is about 0.23-2.86 mm. The modified Gash model is suitable for simulating the canopy interception of the monsoon evergreen broad-leaved forest in the South China Sea.