基于Gash修正模型模拟侧柏及其混交林的林冠截留过程

生态学杂志

基于Gash修正模型模拟侧柏及其混交林的林冠截留过程

李亦然¹,马睿²,张永涛¹,程甜甜³,李泽东¹,牛勇^1*

（¹山东农业大学林学院,山东省土壤侵蚀与生态修复重点实验室,泰山森林生态系统定位研究站, 山东泰安 271018；²山东省泰安市水土保持科学研究所, 山东泰安 271018；³山东省莱芜市水土保持办公室, 山东莱芜 271100）

出版日期:2019-05-10 发布日期:2019-05-10

Simulation of canopy rainfall interception of Platycladus orientalis forest and its mixed forest using the modified Gash model.

LI Yi-ran¹, MA Rui², ZHANG Yong-tao¹, CHENG Tian-tian³, LI Ze-dong¹, NIU Yong^1*

(¹Forestry College of Shandong Agricultural University, Shandong Provincial Key Laboratory of Soil Erosion and Ecological Restoration, Taishan Forest Ecosystem Station of State Forestry Administration, Taian 271018, Shandong, China; ²Institute of Soil and Water Conservation Sciences, Taian 271018, Shandong, China; ³Office of Laiwu Water Conservancy, Laiwu 271100, Shandong, China).

Online:2019-05-10 Published:2019-05-10

摘要/Abstract

摘要：

为探究Gash修正模型对纯林及混交林林冠截留模拟的适用性和差异性，以北京市八达岭森林公园侧柏纯林和侧柏黄栌混交林为研究对象，以研究区2013年5—10月的实测资料为基础数据，运用Gash修正模型对其林冠截留过程进行模拟，并分析模型参数敏感性。结果表明：（1）侧柏(Platycladus orientalis)纯林的穿透降雨量、树干茎流量和林冠截留量的实测值分别为395.2、22.3和129.5 mm，相对应的Gash修正模型模拟值分别为415.80、18.04和113.09 mm，相对误差分别为5.2%、19.0%和12.7%；侧柏黄栌(Cotinus coggygria)混交林的穿透降雨量、树干茎流量和林冠截留量的实测值分别为414.6、12.2和120.1 mm，相对应的Gash修正模型模拟值分别为454.26、10.27和82.40 mm，相对误差分别为9.6%、15.6%和31.4%；（2）选择Gash修正模型中的饱和林冠持水能力（S）、平均降雨强度（R）、饱和林冠平均蒸发速率（E）、郁闭度（c）、树干持水能力（S_t）和树干茎流系数（P_t）共6项参数，进行敏感性分析。对于侧柏纯林，当各参数在-50%～-20%范围内变化时，模拟林冠截留量对各项参数的变化敏感性排序为S>c>E>R>c>S_t>P_t，而当参数在-20%～50%范围内变化时，其排序为S>E>R>c>S_t>P_t；对于侧柏黄栌混交林，模拟林冠截留量对各项参数的变化敏感性排序为S>E>R>c>S_t>P_t。综上，Gash修正模型对于侧柏黄栌混交林的模拟精度较侧柏纯林小，但可满足应用需要；参数S是影响侧柏黄栌混交林和侧柏纯林中的Gash修正模型模拟精度的重要因素。

关键词: 渭北旱塬, 水分调控, 双元覆盖, 水分变异

Abstract: The modified Gash model is commonly used to simulate the canopy interception process. We explored its applicability in a Platycladus orientalis pure forest and a mixed forest of P. orientalis andCotinus coggygria located in Badaling Forest Park of Beijing. Data from May to October in 2013 were collected and used to fit the modified Gash model. The sensitivity of the model parameters was analyzed. The results showed that the measured values of throughfall, stem flow and canopy interception in the P. orientalis pure forest were 395.2, 22.3 and 129.5 mmrespectively, and those measured values of the mixed forest were 414.6, 12.2 and 120.1 mm respectively. Based on the modified Gash model, the simulated values of throughfall, stem flow and canopy interception in the pure forest were 415.80, 18.04 and 113.09 mm respectively, with the relative errors being 5.2%, 19.0%, and 12.7% compared with the measured values. The simulated values of the mixed forest were 454.26, 10.27 and 82.40 mm, with the relative errors of 9.6%, 15.6% and 31.4%. The following indices, saturated canopy waterholding capacity (S), average rainfall intensity (R), average saturated canopy evaporation rate (E), canopy density (c), saturated trunk storage capacity (S_t) and stem flow coefficient (P_t) were used in the sensitivity analysis. The results of sensitivity analyses showed that, in the pure forest, when the parameters varied between -50% to -20%, the simulated canopy interception was the most sensitive to the parameter S, followed by c, R,E, S_t and P_t. When the parameters varied between -20% to 50%, the parameter S also was the most sensitive factor for the simulated canopy interception, followed by E,R,c, S_t and P_t. In the mixed forest, when the parameters varied between -50% to +50%, the simulated canopy interception was the most sensitive to the parameter S, followed by E, R, c, S_t and P_t. According to results of accuracy analysis, we suggest that the modified Gash Model was more suitable for the P. orientalis pure forest than for the mixed forest of P. orientalis and C. coggygria. The parameter S was a primary factor affecting the accuracy of the model output.

Key words: Weibei rainfed highland, soil moisture control, dual mulching, soil moisture variation.

李亦然,马睿,张永涛,程甜甜,李泽东,牛勇. 基于Gash修正模型模拟侧柏及其混交林的林冠截留过程[J]. 生态学杂志.

LI Yi-ran, MA Rui, ZHANG Yong-tao, CHENG Tian-tian, LI Ze-dong, NIU Yong. Simulation of canopy rainfall interception of Platycladus orientalis forest and its mixed forest using the modified Gash model.[J]. cje.