塔里木河下游胡杨林耗水数值模型  

Numerical model of water consumption of Populus euphratica in the lower reaches of Tarim River

作　　者：苏里坦[1] 关东海 王兴勇[3] 赵天宇[1] 

机构地区：[1]中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室,新疆乌鲁木齐830011 [2]新疆水利水电科学研究院,新疆乌鲁木齐830049 [3]中国水利水电科学研究院水力学研究所,北京100038

出　　处：《水科学进展》2014年第4期511-517,共7页Advances in Water Science

基　　金：国家自然科学基金资助项目(41071026)~~

摘　　要：基于SHAW(Simultaneous Heat and Water)模型,以基本观测要素、植被参数和土壤剖面水热观测数据为模型的输入,对河岸胡杨林的耗水过程、土壤剖面水分变化和能通量进行了较小时间尺度上的模拟研究。结果表明,采用SHAW模型模拟的胡杨耗水量与观测值间存在较大偏差。因此,为了进一步提升水热耦合SHAW模型在干旱区的实用性,引入了地下水位因子GSI(Groundwater-Soil water Interaction),建立了改进的SHAW(GSI-SHAW)模型,解决干旱区荒漠河岸林耗水过程模拟的方法问题。采用SHAW模型和GSI-SHAW模型对胡杨耗水量的模拟进行了对比研究。结果显示,SHAW模型和GSI-SHAW模型模拟的胡杨耗水量与观测值的相关性系数分别为0.853 3、0.907 5,其平均相对误差分别为21.4%、16.9%,可见,改进的SHAW模型的模拟值更加接近试验观测值。地下水位的考虑一定程度上提升了传统SHAW模型的模拟精度,为干旱区自然植被耗水量的计算提供了新的方法和科学依据。Water consumption of vegetation is the core of SPAC （Soil-Plant-Atmosphere Continuum） research; it＇s also the precondition on the research of water requirements by natural vegetation. This paper simulated the water con sumption of riparian Populus euphratica forests, the representative natural vegetation in the lower reaches of Tarim River, in a relatively small time scale based on the SHAW（Simultaneous Heat and Water） model. Conventional weather elements, vegetation parameter and hydrothermal data of soil profile were adopted as initial inputs of the model. The results show that there is a deviation between the simulated value and observed value of water consumption by Populus euphratica forests. To further improve the appropriateness of the SHAW model application in arid regions, we estab- lished a modified SHAW model by introducing the groundwater level factor GSI （Groundwater_Soil water Interaction）. We comparatively analyzed the water consumption of Populus euphratica by the two models of SHAW and GSI-SHAW. The results show that the correlation coefficients between simulated and observed water consumption are 0. 853 3 and 0. 907 5 by SHAW model and GSI-SHAW model, respectively. The relative errors of simulated values by SHAW model and GSI-SHAW model are respectively 21.4% and 16.9% against observed water consumption rates. It can be seen that the simulated values of the modified GSI-SHAW model are more approximate to the measured values. We conclude that the integration of GSI model further improves the simulation accuracy of SHAW model, providing a new method and scientific proof for the calculation of water consumption by natural vegetations in arid areas.

关 键 词：胡杨林 耗水 改进SHAW模型 塔里木河下游 中国西北干旱区 

分 类 号：P343.1[天文地球—水文科学]