1960—2020年千岛湖流域蒸散发演变特征及驱动因素解析  

Evolution characteristics and influencing factors of evapotranspiration in Lake Qiandao Basin from 1960 to 2020

作　　者：董颢 杜军凯[1,2] 俞发康 仇亚琴 吕向林[1,2] Dong Hao;Du Junkai;Yu Fakang;Qiu Yaqin;Lv Xianglin(China Institute of Water Resources and Hydropower Research,Beijing 100044,P.R.China;State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,Beijing 100038,P.R.China;Chun an County Ecological Comprehensive Protection Bureau,Hangzhou 311716,P.R.China)

机构地区：[1]中国水利水电科学研究院,北京100044 [2]流域水循环模拟与调控国家重点实验室,北京100038 [3]淳安县千岛湖生态综合保护局,杭州311716

出　　处：《湖泊科学》2024年第3期901-912,共12页Journal of Lake Sciences

基　　金：国家自然科学基金项目(52279030);国家重点研发计划项目(2021YFC3201101,2021YFC3201105)联合资助。

摘　　要：为探究淡水湖库及其所属流域蒸散发演变特征,以及气象因子对蒸散发的影响规律。以长三角地区最大的淡水人工湖和重要的水源地--千岛湖为研究对象,采用Penman-Monteith等方法与WEP-L分布式水文模型,分别计算千岛湖流域1960-2020年潜在蒸散发(ET_(0))与实际蒸散发(ET_(a)),分析二者年际变化趋势及突变年份;采用偏微分方法分析气象因子对ET_(0)的敏感性和贡献度;采用归因分析法分析突变前后气象因子对ET_(a)变化的贡献度,并利用蒸发表面水分指数(EM_(1))解析流域蒸发互补关系。结果表明:ET_(0)与ET_(a)多年平均值分别为1021.7和857.5 mm,整体皆呈减少趋势,倾向率分别为-0.77和-1.03 mm/a,二者均在1980和2000年左右发生突变;ET_(0)对相对湿度变化最为敏感,ET_(0)增加的月份主要是由于相对湿度、平均气温的正贡献,风速呈负贡献但相对较小,ET_(0)减少的月份主要是由于日照时数和风速的负贡献,平均气温呈正贡献但相对较小;ET_(a)空间分布呈现东高西低格局,驱动因素按贡献率大小为相对湿度>风速>日照时数>气温;流域整体存在“蒸发悖论”现象,日照时数和风速的减小是引起ET_(0)近年来下降的主要原因;EM1愈趋近于1时,反映流域ET_(0)和ET_(a)取值愈加接近,蒸散发互补理论在千岛湖流域适用。The largest freshwater artificial lake and important water source in the Yangtze River Delta region,Lake Qiandao,was chosen as the research region to explore the evolvement characteristics of evapotranspiration in freshwater lakes and their watersheds,as well as the influence of meteorological elements on evapotranspiration.The Penman-Monteith method and WEP-L distributed hydrological model were employed to calculate the potential evapotranspiration(ET_(0))and actual evapotranspiration(ET_(a))in the Lake Qiandao basin from 1960 to 2020.The annual variations and mutation years of both ET_(0)and ET_(a)were analyzed.The sensitivity and contribution of meteorological elements to ET_(0)were analyzed using the partial derivative method.The contribution of meteorological elements to the change in ET_(a)before and after the mutation was analyzed using the attribution analysis method.Additionally,the evaporative surface water index(E_(MI))was used to analyze the complementarity of basin evapotranspiration.The results showed that the multi-year average values of ET_(0)and ET_(a)were 1021.7 and 857.5 mm,respectively,both exhibiting decreasing trends with inclination rates of-0.77 and-1.03 mm/a.Both ET_(0)and ET_(a)experienced mutations around 1980 and 2000.Relative humidity had the highest sensitivity to ET_(0)changes,and ET_(0)increased mainly due to positive contributions from relative humidity and average temperature,with wind speed making a relatively small negative contribution.ET_(0)decreased mainly due to negative contributions from sunshine duration and wind speed,with average temperature making a relatively small positive contribution.The spatial distribution of ET_(a)showed an east-high and west-low pattern,with the driving factors in order of contribution rate being relative humidity,wind speed,sunshine duration,and temperature.The basin exhibited an“evaporation paradox”and the reduction in sunshine duration and wind speed were the main reasons for the recent decline in ET_(0).As E MI approaches 1,it indicate

关 键 词：流域蒸散发 气候变化 互补关系 千岛湖 新安江水库 

分 类 号：P333.1[天文地球—水文科学]