近60 a石羊河流域蒸发量变化及其原因分析  

Analysis of change and causes of evaporation for the Shiyang River Basin during the past 60 years

作　　者：李小琴 冉宸 张晓霞 冉新民[4] LI Xiaoqin;RAN Chen;ZHANG Xiaoxia;RAN Xinmin(Lanzhou Resources&Environment Voc-Tech University,Lanzhou 730050,Gansu,China;Zhejiang Institute of Hydraulics&Estuary,Zhejiang Institute of Marine Planning and Design,Hangzhou 310000,Zhejiang,China;Nine-Year School of Chengguan Zhouqu,Zhouqu 746300,Gansu,China;School of Resources and Environment,Lanzhou University,Lanzhou 730000,Gansu,China)

机构地区：[1]兰州资源环境职业技术大学,甘肃兰州730050 [2]浙江省水利河口研究院(浙江省海洋规划设计研究院),浙江杭州310000 [3]舟曲县城关九年制学校,甘肃舟曲746300 [4]兰州大学资源环境学院,甘肃兰州730000

出　　处：《干旱区研究》2022年第3期745-753,共9页Arid Zone Research

基　　金：国家重点研发计划课题(2018YPC1802905)资助。

摘　　要：蒸发是水循环的关键环节,理解蒸发变化及其原因对于水资源可持续利用具有重要意义。以石羊河流域为例,选取自南向北沿海拔梯度递减的乌鞘岭、永昌、武威和民勤4个气象站近60 a(1958—2017年)数据资料,基于改进的PenPan模型分析了石羊河流域蒸发量时空变化特征及其原因。结果表明:(1)空间上,石羊河流域蒸发量变化存在海拔效应,随着海拔的增加蒸发量显著减少,递减率约为38 mm·(100m)^(-1);时间上,蒸发量变化存在明显的分段特征,1958—1970年蒸发量减少,20世纪70年代以来蒸发量增加,尤其是平原区最为明显。(2)改进的PenPan模型能较好地模拟各站点日尺度和月尺度蒸发量的变化(R2>0.85),为进一步提高模拟精度,模型中的风速函数有待修正。(3)改进的PenPan模型计算的辐射组分年际变化不大,但空气动力学组分波动上升,这与温度和饱和水气压差变化趋势一致,说明温度升高是引起石羊河流域70年代以来蒸发量增加的主要原因。说明在气候变暖背景下石羊河流域蒸发量将持续增加,也给未来强化水资源管理,保障可持续发展施加更大的压力。Evaporation is an essential component in hydrological processes,and understanding the change and causes of evaporation is of importance for sustainable management of water resources.Based on the four selected meteorological stations,Wushaoling,Yongchang,Wuwei and Minqin,of which ranged along the altitudinal gradient from 1958 to 2017,the study analysed the change of evaporation and its causes based on the modified PenPan model for the Shiyang River Basin.The results shown that(1)the spatially variation of evaporation can attribute to the altitude effects,namely the evaporation decreased with a rate of 38 mm for every 100 m elevation increase,and temporally change has the significant stage differentiation features,i.e.decreased in 1958-1970,whereas increased after 1970,that particularly obvious in the plain areas of low elevation but not in mountainous area;(2)there was a good agreement with the R2 greater than 0.85 between the observed evaporation and calculated by the modified PenPan model whether in daily or monthly time-scale,however,the wind speed function need amend further in order to obtain the robust performance;and(3)the yearly change of radiative component was relatively stable,but the aerodynamic component of evaporation increase fluctuated,of which was in consistent with the change of temperature and vapor pressure deficit,suggest that the rised temperature is the major reason for the increase of evaporation in Shiyang River Basin after 1970.The result means that the evaporation will increased under climate warming,it will impose more stress on the water resource sustainable management in the future.

关 键 词：蒸发皿蒸发 PenPan模型 组分分割 石羊河流域 

分 类 号：P339[天文地球—水文科学]