BNU-ESM-RCP4.5情景下2018～2060年拒马河河道内生态需水量和麦穗鱼栖息地面积模拟研究

Simulation of Instream Ecological Flow Requirement and Suitable Physical Habitat Area for Pseudorasbora parva in Juma River During 2018 to 2060 under the BNU-ESM-RCPNU-ESM-RCP4.5 Scenario

选取拒马河为研究对象,采用SWAT模型和River2D模型,利用IPCC第五次报告中的BNU-ESM-RCP4.5模式的模拟数据,对2018~2060年紫荆关水文站附近3 km长的拒马河河段河道内径流量和麦穗鱼(Pseudorasbora parva)栖息地面积进行了模拟和分析。研究结果表明,1956~2015年期间,河道内年径流量呈减少趋势,平均每年径流量减少0.1×108m^3,2018~2060年期间,年径流量呈增加趋势,平均每年径流量增加0.05×108m^3;河道内年生态需水量为4.11×108~7.42×108m^3,模拟的2018~2030年期间河道内年径流量难以满足其生态需水量的需求,而2031~2060年期间的年径流量基本能够满足生态需水量的需求;除秋季外,其它季节的径流量难以满足生态需水量的需求;2018~2060年期间,河道内的麦穗鱼最适物理栖息地面积呈增加趋势,且秋季其栖息地面积明显增加。

To understand the impacts of climate change on streamflow and ecological flow requirement is of great significance to the ecological management of rivers. In this study, we applied the SWAT model and River2 D model to analyze the influence of climate change on the streamflow and physical habitat area in a 3 km channel of Juma River around Zijingguan hydrological station by using the RCP4.5（Representative Concentration Pathway 4.5） scenario of the coupled earth system model of Beijing Normal University（BNU-ESM）.The results showed that the annual instream flow in the Juma River presented a decreasing trend during1956-2015 with a slope of-0.1 × 108m^3/yr, while it presented an increasing trend during 2018-2060 with a slope of 0.05×108m^3/yr; and the annual total instream ecological flow requirement in the Juma River ranged from 4.11×108to 7.42×108m^3; and the streamflow could basically meet the ecological flow requirement during 2031-2060, while it could not meet the instream ecological flow requirement during 2018-2030. Especially, except for autumn, inter annual streamflow could not meet the ecological flow requirement; and the suitable physical habitat area for Pseudorasbora parva during 2018-2060 presented increasing trends, especially in autumn. The results should be helpful to understand the impacts of climate change on ecological flow requirement, and to provide suitable measures to maintain the integrity of rivers.