气候与植被覆盖变化对中国西南亚高山区流域碳水循环的影响模拟  

Simulations of the Impact of Climate and Vegetation Cover Changes on Carbon and Water Cycles of a Subalpine Basin in the Mountain Region of Southwestern China

作　　者：邓慧平[1] 丹利[2] 王倩[1] 杨秀静 杨富强 DENG Huiping;Dan Li;WANG Qian;YANG Xiujing;YANG Fuqiang(School of Environment and Planning,Liaocheng University,Liaocheng,Shandong Province 252059;Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029)

机构地区：[1]聊城大学环境与规划学院,山东聊城252059 [2]中国科学院大气物理研究所东亚区域气候—环境重点实验室,北京100029

出　　处：《气候与环境研究》2020年第1期19-31,共13页Climatic and Environmental Research

基　　金：国家重点研发计划项目2016YFA0602501;国家自然科学基金重点项目41630532~~

摘　　要：正确认识气候变化对流域森林植被和水文的影响对于林业经营管理与流域生态修复具有重要意义。为了揭示气候与植被覆盖变化对西南亚高山区流域碳水循环过程的影响,用生物物理/动态植被模型SSiB4/TRIFFID(Simplified Simple Biosphere model version 4,coupled with the Top-down Representation of Interactive Foliage and Flora Including Dynamics model)与流域地形指数水文模型TOPMODEL(Topographic Index Model)的耦合模型(以下记为SSiB4T/TRIFFID)模拟了不同气候情景下西南亚高山区的梭磨河流域植被演替和碳水循环过程。结果表明,所有试验流域植被经历了从C3到苔原灌木最后到森林的变化;控制试验流域蒸散在流域植被主要为苔原灌木时达到最大而径流深最小;增温5℃并且增雨40%试验[记为T+5,(1+40%)P试验]流域蒸散在流域为森林覆盖时达到最大而径流深最小。随着温度增加,森林蒸腾、冠层截留蒸发和蒸散的增加幅度明显大于草和苔原灌木,导致森林从控制试验的增加径流量变为减小径流量。从控制试验到T+5,(1+40%)P试验,温度增加使森林净初级生产力有所增加,但对草和苔原灌木的净初级生产力影响很小;植被水分利用效率随温度增加明显减小。西南山区随着海拔高度降低(温度升高),森林从增加径流量转变为减少径流量,植被水分利用效率也相应明显减小。西南山区气候的垂直地带性对森林—径流关系和水分利用效率的空间变化有着重要的影响。Correctly understanding the hydrological impacts of forest vegetation and climate change is of considerable significance for forestry management and watershed ecological restoration.To investigate the effects of climate and vegetation cover changes on carbon-water cycles,the biophysical/dynamic vegetation model SSiB4/TRIFFID(Simplified Simple Biosphere model version 4,coupled with the Top-down Representation of Interactive Foliage and Flora Including Dynamics model)was coupled with the TOPMODEL(Topographic Index Model)based on the catchment scheme partitions between saturated and unsaturated zones.The coupled model(hereinafter SSiB4T/TRIFFID)was employed to perform long-term dynamic simulations of vegetation succession and carbon-water circulations under different climate scenarios for a subalpine basin(the Soumou River basin that is a tributary of the Yangtze River located in the mountain region of southwestern China).The results of all tests indicate that vegetation fractions initially undergo changes from C3 grass dominance to tundra shrub dominance and then gradually approach equilibrium forest dominance.The results of the control test show that evapotranspiration of the basin increases and reaches its maximum value and runoff reaches its minimum value during the succession period of C3 grasses into tundra shrubs.Additionally,evapotranspiration decreases and runoff increases during the succession period of tundra shrubs into forests.An increase in temperature by 2℃enhances the rate of transpiration and canopy interception evaporation of forests more than those of grasses and tundra shrubs.As a result,the role of forests in increasing runoff is reduced.An increase in temperature by 5℃accompanied by an increase in precipitation by 40%[T+5,(1+40%)P test]will cause forests to reduce runoff because of the considerable increase in water loss through canopy interception evaporation and transpiration of forests.The results indicate that sensitivity to temperature changes of canopy interception evaporation and tra

关 键 词：陆面模式 碳水循环模拟 气候与植被变化影响 森林—径流关系 水分利用效率 

分 类 号：P426.2[天文地球—大气科学及气象学]