内蒙古半干旱区蒸散特征及归因分析  

Evapotranspiration changes and its attribution in semi-arid regions of Inner Mongolia

作　　者：赵晓涵 张方敏[1,2] 韩典辰 翁升恒 ZHAO Xiaohan;ZHANG Fangmin;HAN Dianchen;WENG Shengheng(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;Jiangsu Key Laboratory of Agricultural Meteorology,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China)

机构地区：[1]南京信息工程大学,气象灾害预报预警与评估协同创新中心,江苏南京210044 [2]南京信息工程大学,江苏省农业气象重点实验室,江苏南京210044

出　　处：《干旱区研究》2021年第6期1614-1623,共10页Arid Zone Research

基　　金：科技部重大研发计划(2018YFC1506606);江苏省优秀青年基金项目(BK20170102)。

摘　　要：探讨蒸散(ET)变化特征及其影响因素对区域水资源有效利用至关重要。本文基于BEPS(Boreal Ecosystem Productivity Simulator)模型,结合遥感数据和气象数据模拟了内蒙古半干旱区1981—2018年ET变化特征并量化了其影响因子的贡献。研究发现,1981—2018年内蒙古半干旱地区ET以1.75 mm·a^(-1)的速度呈波动上升趋势(P<0.05);同时,ET变化存在年代际差异,在1997年发生明显突变,1998—2018年ET以1.70 mm·a^(-1)的速度增加(P<0.05)。大气水分亏缺(VPD)和LAI在1997年后每年分别以0.002 hPa和0.01的速度显著增加(P<0.05),弥补了其他因子的不利影响,导致了ET显著增加。通径分析和回归分析结果表明,ET变化主要受到VPD的直接作用驱动,通径分析的决定系数达0.95,由VPD主导ET变化的区域占内蒙古半干旱区面积的93.56%,能够解释ET变化的24.83%~90.46%。同时,VPD也是耕地、林地、草地、城市和裸地5种土地利用类型上ET变化的主要影响因素,平均能够解释45%以上的ET变化。Understanding the variation characteristics of evapotranspiration(ET)and its influencing factors are essential for regional water resources.Based on the boreal ecosystem productivity simulator model,remote sensing data,and meteorological data,the characteristics of ET change in semiarid regions of Inner Mongolia from 1981 to 2018 were simulated and its driving factors were quantified.ET of semiarid regions in Inner Mongolia showed a fluctuating upward trend with a rate at 1.75 mm·a^(-1)(P<0.05)from 1981 to 2018.Further,there were concurrent differences in ET with a significant mutation happened in 1997.ET increased at a rate of 1.70 mm·a^(-1) in 1998-2018(P<0.05).Vapor pressure deficit(VPD)and LAI were the main driving factors of ET changes after 1997,which significantly increased at a rate of 0.002 hPa and 0.01 per year(P<0.05).The adverse effects of other factors were suppressed in positive influence of VPD and LAI,which led to a significant increase in ET.VPD was the main driving factor of ET change,which dominated regional ET change in 93.56%of the area and explained 24.83%-90.46%of ET change,where the coefficient of determination for path analysis was 0.95.VPD was the primary factor driving the five land use types of cultivated land,forestland,grassland,urban land,and bare land with average contribution rates of more than 45%.

关 键 词：蒸散 大气水分亏缺 BEPS模型 叶面积指数 内蒙古 

分 类 号：P426.2[天文地球—大气科学及气象学]