秦岭山区潜在蒸散发时空变化及典型流域径流归因分析  

Spatiotemporal variation of potential evapotranspiration in the Qinling Mountain Areas and attribution analysis of typical watershed runoff

作　　者：贾路 于坤霞[1] 李占斌[1] 李鹏[1,3] 徐国策[1,3] 赵宾华[1,3] 高蓓 杨志 JIA Lu;YU Kunxia;LI Zhanbin;LI Peng;XU Guoce;ZHAO Binhua;GAO Bei;YANG Zhi(State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China,Xi′an University of Technology,Xi′an 710048,China;Key Laboratory of Hydrologic-cycle and Hydrodynamic System of Ministry of Water Resources,Hohai University,Nan′ing 210098,China;Key Laboratory of National Forestry and Grassland Administration on Ecological Hydrology and Disaster Prevention in Arid Regions,Xi′an University of Technology,Xi’an 710048,China;Xi’an Water Conservancy Planning Survey and Design Institute,Xi’an 710054,China;Hydraulic Research Institute of Ningxia Hui Autonomous Regine,Xi’an 750002,China)

机构地区：[1]西安理工大学西北旱区生态水利国家重点实验室,西安710048 [2]河海大学水利部水循环与水动力系统重点实验室,南京210098 [3]西安理工大学旱区生态水文与灾害防治国家林业和草原局重点实验室,西安710048 [4]西安市水利规划勘测设计院,西安710054 [5]宁夏回族自治区水利科学研究院,银川750002

出　　处：《农业工程学报》2024年第24期59-71,共13页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(U2040208);陕西省重点研发计划项目(2023-ZDLSF-60);陕西省青年科技新星项目(2024ZC-KJXX-058);宁夏水利科学研究院项目(SKYZY-2024005)。

摘　　要：山区流域作为水源涵养地,由于地形、植被和气候因子间的复杂相互作用,与平原流域相比,其对气候变化更为敏感,在水资源稳定性和生态环境保护等方面面临着更严峻的挑战。为掌握山区流域水文变化规律,该研究以秦岭山区及其内部6个典型流域为研究对象,基于1965—2019年79个气象站日气象数据和6个典型流域控制水文站逐年径流数据以及年太阳黑子数、大气环流指数、Nino3.4指数,采用Penman-Monteith公式、改进的Mann-Kendall趋势检验法、微分法、交叉小波变换和时变Budyko框架分析了秦岭山区年潜在蒸散发(potential evapotranspiration,PET)的时空变化特征,计算了年PET对不同气候因子的敏感性,探讨了年PET变化的可能原因,最后量化了PET等不同因素对径流在不同时期变化的贡献率。结果表明:1)在1965—2019年间,秦岭山区的多年平均PET和气候因子表现出明显的空间分布差异和变化趋势。多年平均PET和日照时数呈现东北高、西南低的空间分布格局,最大和最小相对湿度则在空间上表现出相反的趋势变化特征。此外,在年尺度上,气温普遍上升,而日照时数和风速在大面积范围内有所下降。2)年PET在草原植被区对多个气候因子的敏感性最高。地形因子、太阳黑子活动、大气环流和海温变化等因素对年PET的影响时段和范围存在差异。98.73%气象站点的年PET与北极涛动指数呈现负相关,呈现显著负相关的比例高达20.25%(P<0.05)。这证明了北极涛动通过影响区域性的气候模式,间接影响了该地区的蒸散发过程。特别是在北极涛动的负位相时,常常伴随冷空气南下,导致该区域温度下降,蒸散发减少。随着海拔和坡度的增加,PET表现出极显著的减少趋势(P<0.001)。3)在6个典型流域中,流域径流变化主要受降水和下垫面条件的驱动,尤其是植被变化对径流的影响逐渐增强。研究成果将支撑山区�Mountain watersheds,as the critical regional water sources,are highly sensitive to climate change.It is a high demand to investigate the hydrological variations in mountain watersheds for the protection of regional ecological environments and sustainable water resources.This study aims to explore the spatiotemporal variation in the potential evapotranspiration and attribution analysis of typical watershed runoff in the Qinling Mountain Areas.Six typical watersheds were selected as the research objects.Meteorological data was daily collected from 79 meteorological stations from 1965 to 2019.Annual runoff data was from the hydrological control stations in the watersheds,together with the annual sunspot numbers,atmospheric circulation indices,and the Nino3.4 index,such as the Penman-Monteith equation.The modified Mann-Kendall trend test was employed to analyze the spatiotemporal variations in the potential evapotranspiration(PET)across the study area using cross-wavelet transforms and the time-varying Budyko framework.PET sensitivity was assessed on various climatic factors to explore the potential drivers of PET changes.Finally,the contributions of PET were quantified for the runoff variations across different periods.The results indicated:1)There were some significant differences in spatial distribution and trends in the multi-year average PET and climate factors from 1965 to 2019.Multi-year average PET and sunlight hours(SH)exhibited a spatial pattern of higher in the northeast and lower in the southwest.While the maximum and minimum relative humidity(RHmax and RHmin)showed the opposite trends.Additionally,the temperature generally increased on an annual scale,while the SH and wind speed(WS)decreased across a broad area.The average annual WS of all vegetation types was below 1.8 m/s.The significant reduction in the annual WS was concentrated mainly in the vegetation types,such as the broad-leaved forest,cultivated vegetation,shrub,coniferous forest,and grass(P<0.05).It was also found that the differential modes w

关 键 词：蒸散发 时空变化 径流 Budyko 秦岭山区 

分 类 号：P426.2[天文地球—大气科学及气象学]