摘要
天山区域地形多变,景观异质性强,水文过程极其复杂,全球变化对该地区水安全带来新的挑战和更大不确定性。亟需通过流域水文模型系统定量模拟和预估天山典型流域水文过程,以更好地支撑区域发展。本研究基于改进的FLEXG-Δh模型,定量模拟了天山4个典型流域的历史径流过程,并预估了流域内2282条冰川物质平衡和面积的未来变化,进一步通过情景模拟分析了各海拔高程带径流等水文多要素的响应机制。研究发现:(1)FLEXG-Δh模型对历史径流过程具有较高模拟精度,率定期平均Kling-Gupta效率系数(IKGE)为0.75,检验期平均IKGE为0.60。(2)随海拔上升,径流量和蒸发量呈现先增后减趋势,最大值分别出现在海拔4000 m和2000 m,并分别受冰川覆盖和植被分布影响。(3)未来到2100年,低于4500 m海拔的冰川消融明显。在SSP1-RCP2.6和SSP5-RCP8.5情景下,研究区内分别有145和222条冰川完全消融,冰川总体积分别减少1.81×10^(4)km^(3)(占现有冰川体积的54%)和2.44×10^(4)km^(3)(占现有冰川体积的73%)。在SSP5-RCP8.5情景下,升温导致蒸发量增加,与冰川变化叠加,导致径流深在海拔4000 m以下地区减少0.16~1.40 mm·a^(-1),在4000 m以上地区则增加0.20~0.67 mm·a^(-1)。本研究揭示了天山地区景观垂直地带性(森林、冰川等)与气候(水分和热量)间很强的时空规律性,并预估了全球变化对天山地区水资源垂直地带性的影响,以期为区域水资源合理利用和可持续发展提供支撑。
Because of varied topography and landscape heterogeneity,Tianshan Mountain has extremely com⁃plex hydrological processes.Considering that the climate change poses a great threat to the water security,it’s necessary to simulate the change of water elements quantitatively and systematically along with elevation.In this study,we applied the modified FLEXG-Δh model to four classic river basins in Tianshan Mountain in consider⁃ation of glacier area changes.The results suggested that:(1)FLEXG-Δh model has high simulation accuracy for the historical runoff process because the average Kling-Gupta coefficient(IKGE)in calibration is 0.75 and IKGE in validation is 0.60.(2)Precipitation increases along with elevation while runoff and evaporation increase first but then decreased,with the maximum values at 4000 m and 2000 m respectively.The height zone with the greatest runoff is mainly affected by the glacier cover,while it is the distribution of forest for the greatest evapo⁃ration.(3)By 2100,the glaciers at low altitudes will melt significantly,while there will be a little melting above 4500 m.Under SSP1-RCP2.6 and SSP5-RCP8.5 scenarios,145 and 222 glaciers will completely melt and the volume of glaciers will decrease 1.81×10^(4)km^(3)(54%of the existing glaciers)and 2.44×10^(4)km^(3)(73%of the existing glaciers),respectively.In the SSP5-RCP8.5 scenario,the rise of temperature will increase the evap⁃oration but lead to the fact that the runoff depth will decrease 0.16~1.40 mm·a^(-1)below 4000 m and increase 0.20~0.67 mm·a^(-1)above 4000 m,causing the height of peak value will go up by about 500 m.Under SSP1-RCP2.6 scenario,there will be few obvious changes.This study presented the vertical zonal law of hydrology and vegetation,and predicted the impact of global changes on the Tianshan Mountains,which provided theoreti⁃cal support for water utilization and sustainable development.
作者
倪静雯
高红凯
秦延华
张文鑫
何天豪
雍磊磊
冯紫荆
NI Jingwen;GAO Hongkai;QIN Yanhua;ZHANG Wenxin;HE Tianhao;YONG Leilei;FENG Zijing(School of Geographic Sciences,East China Normal University,Shanghai 200241,China;School of Geography and Tourism,Qufu Normal University,Rizhao 276826,Shandong,China;Department of Physical Geography and Ecological Science,Lund University,Lund SE22362,Sweden)
出处
《冰川冻土》
CSCD
北大核心
2023年第6期1875-1886,共12页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(42122002,42071081)
瑞典国家自然科学基金项目(VR 2020-05338)
瑞典国家空间局基金项目(SNSA 209/19)资助。
