中国水土保持科学2017，Vol.15Issue(6)：27-33,7.DOI:10.16843/j.sswc.2017.06.004
基于Gash模型对华北落叶松和油松人工林冠层截留的模拟
Canopy interception simulation of Larix principis-rupprechtii and Pinus tabulaeformis forests in northern China based on Gash model
摘要
Abstract
[Background] The interception process of forest canopy is a key of forest hydrology,which directly affects the prediction of hydrological cycle and forest soil and water conservation function.There are many influencing factors which are researched by scholars,and then,how to find a quick and accurate method has become a hot topic recently.One of these methods used widely is Gash model,and this paper verifies the applicability of Gash analytical model in Larix principis-rupprechtii and Pinus tabulaeformis forests in northern China.[Methods] Rainfall outside of stands,throughfall and stemflow of 3 L.principis-rupprechtii forest plots and 3 P.tabulaeformis forests plots in Mulan Forestry Management Bureau in Weichang County of Hebei Province during trees growing season of 2015 were measured and canopy interception was simulated combined with environmental and meteorological data.The core of the research methodology was to determine the accuracy of the Gash model parameters,including air temperature,temperature of soil depth,relative humidity,saturation vapor pressure,vapor pressure,open wind speed,air pressure,forest area net radiation flux,soil heat flux,psychometric constant and slope of the saturated vapor pressure curve at the temperature of air.In the process of simulation,regression method was used to determine canopy parameters and difference between intercepts of curves,which showed the relationship between stemflow and rainfall outside of stands and water storage capacity of leaves and branches was used as water storage capacity of tree trunks.[Results] Canopy water storage capacity of planted L.principis-rupprechtii forests was (1.72 ± 0.48) mm for leaves and branches and (1.16 ± 0.89) mm for tree trunks.Canopy water storage capacity of planted P.tabulaeformis forest was (2.60 ± 0.23)mm for leaves and branches and (1.46 ± 0.65) mm for tree trunks.The amounts of rainfall needed to saturate the canopy of L.principis-rupprechtii forests and P.tabulaeformis forest were (2.50 ± 0.53)mm and (2.98 ± 0.63)mm respectively.The scope of evaporation rate of plots was from (1.14 × 10-1 to 1.42 × 10-1) mm/h in rainfall periods.The total values of canopy were 26.9,38.34 and 38.29 mm,respectively,and the simulated values were 27.95,41.22,and 38.32 mm,the relative error range was 0.07％-7.51 ％.The simulated values of canopy total were 54.37,55.62,and 33.03 mm,the simulated values were 51.37,52.69,and 35.23 mm,and the relative error ranged in 5.26％-6.66％.[Conclusions] There were no significant difference of variances and means between simulated value and measured value (P ＞ 0.1) while the correlation of them was high (R =0.99,P ＜ 0.01),indicating the fine simulating effect of Gash analytic model.This study would improve the measurement accuracy of forest canopy interception,rainfall and stemflow of two main tree species,and provide more accurate numerical simulation and theoretical basis for hydrological cycle and soil and water conservation in this area.关键词
Gash解析模型/降雨/林冠截留/落叶松人工林/油松人工林Key words
Gash analytic model/rainfall/canopy interception/Larix principis-rupprechtii/Pinus tabulaeformis分类
农业科技引用本文复制引用
魏曦,毕华兴,梁文俊..基于Gash模型对华北落叶松和油松人工林冠层截留的模拟[J].中国水土保持科学,2017,15(6):27-33,7.基金项目
国家重点研发计划资助“黄土残塬沟壑区水土保持型景观优化与特色林产业技术及示范”(2016YFC0501704) （2016YFC0501704）
国家自然科学基金“基于森林空间结构的华北落叶松人工林种子萌发及幼苗成活机制研究”(31500523) （31500523）
