基于幼树模拟降雨实验的树冠动态截留模型  

A dynamic crown interception model based on simulated rainfall experiments of small trees

作　　者：李想 王亚明 孟晨 李娇[4] 牛健植 Li Xiang;Wang Yaming;Meng Chen;Li Jiao;Niu Jianzhi(China National Forestry Economic Development Research Center of State Forestry and Grassland Administration, Beijing 100714, China;Key Laboratory of Soil and Water Conservation ＆ Desertification Combating of State Forestry Administration, Beijing 100083, China;School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China;Xinjiang Academy of Forestry Planning, Urumqi 830000, Xinjiang, China)

机构地区：[1]国家林业和草原局经济发展研究中心,北京100714 [2]水土保持与荒漠化防治国家林业局重点实验室,北京100083 [3]北京林业大学水土保持学院,北京100083 [4]新疆维吾尔自治区林业规划院,新疆乌鲁木齐830000

出　　处：《北京林业大学学报》2018年第4期43-50,共8页Journal of Beijing Forestry University

基　　金："十二五"国家科技支撑计划项目(2011BAD38B05);国家林业局经济发展研究中心青年课题计划(JYQN2016-09)

摘　　要：【目的】为准确刻划林冠截留的动态过程,建立动态截留模型,充分阐释树冠特征和降雨特征对截留过程的影响。【方法】利用北京山区常见4种树木(侧柏、油松、栓皮栎、元宝枫)的幼树,在5种模拟雨强(10、20、50、100、150mm/h)下,通过直接称质量法,测定了树冠动态截留量,剖析了降雨因素和树冠结构特征对截留过程的影响,选择相关参数建立了基于降雨过程的树冠动态截留模型。【结果】(1)树冠截留动态过程可分为快速增加、饱和稳定和滞后冠滴雨3个阶段,降雨结束后近40%的截留量会滴落至地表;(2)截留量是有限的,当场降雨累计降水量达12~13 mm时,累计截留量不再增加;(3)叶片特征(如叶面积、叶面积指数LAI、叶片生物量等)及枝干特征(如枝干面积、枝干生物量、枝干数、枝干长度等)均显著影响截留量,LAI作为易测结构参数与最大和最小截留量均呈幂函数关系;(4)基于累计降雨量(Pc)和LAI可构建动态截留模型验证情况良好,可准确刻画和预测降雨过程中的截留量变化。【结论】树冠截留是一个动态的三相过程,通过累计降雨量和叶面积指数可以实现对动态、截留过程模拟,对量化森林水文循环过程和动态水量平衡具有重要意义。[Objective] The research aims to fully depict the dynamic processes of rainfall interception by tree crown and the effects of crown and rainfall traits on rainfall interception process,and to develop the dynamic interception process simulation model on such basis. [Method]A process-based experiment was conducted under five simulated rainfall intensities（ 10,20,50,100,150 mm/hour） to directly quantify tree crown interception and analyze the effects of rainfall traits and crown structure characteristics on interception. [Result]（ 1） The interception process was composed of three phases,a rapid increase phase,a relatively-stable phase,and a post-rainfall drainage phase,in which 40%（ ± 16%） ofmaximum interception storage（ Cmax） drained off to reach the minimum interception storage（ Cmin）.（ 2）Interception is a threshold process,cumulative interception remained relatively stable when cumulative precipitation（ Pc） surpassed 12-13 mm on a rainfall-event basis.（ 3） Both leaf traits（ i. e.,leaf area,leaf area index,leaf biomass） and branch traits（ i. e.,branch surface area,branch count,branch length,and woody biomass） significantly affected Cmaxand Cmin. The LAI,as an easily-measurable parameter,affects the Cmaxand Cminfollowing a power function.（ 4） A cumulative interception during rainfall（ CIDR） model had been developed based on Pcand LAI： the model worked well and can simulate and predict the cumulative interception amount during rainfall. [Conclusion] Crown interception is a dynamic process with three stages,which can be simulated by a model incorporated cumulative precipitation and LAI as major variables. The model is of great importance to quantify hydrologic processes and water balance in forest ecosystems.

关 键 词：截留过程 叶面积指数 累计降雨量 累计截留量 动态截留模型 

分 类 号：S718.43[农业科学—林学]