气候与下垫面变化对黄土高原蒸散发变化的影响评估  

Assessment on the Impact of Climate and the Changes of Underlying Surface on the Evapotranspiration in the Loess Plateau

作　　者：王凯利 王志慧[2] 肖培青[2] 王铁生 WANG Kaili;WANG Zhihui;XIAO Peiqing;WANG Tiesheng(College of Surveying and Geo-Informatics,North China University of Water Resources and Electric Power,Zhengzhou 450045;Key Laboratory of Soil and Water Conservation on the Loess Plateau of Ministry of Water Resources,Yellow River Institute of Hydraulic Research,Zhengzhou 450003)

机构地区：[1]华北水利水电大学测绘与地理信息学院,郑州450045 [2]黄河水利科学研究院,水利部黄土高原水土保持重点实验室,郑州450003

出　　处：《水土保持学报》2022年第3期166-172,180,共8页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(U2243210,41701509);中央级公益性科研院所基本科研业务费专项(HKY-JBYW-2020-09)。

摘　　要：为了揭示近20年黄土高原蒸散发(evapotranspiration,ET)时空变化规律,明晰气候和下垫面变化对蒸散发的影响作用。基于黄土高原295个气象站数据、PML_V2 ET产品及MOD13A1 EVI产品,采用趋势分析和多元回归分析等统计方法,分析了2000—2018年黄土高原蒸散发时空变化特征,并评估了降雨、温度、日照时间、饱和水汽压差、植被和非植被下垫面等影响要素的相对贡献率。结果表明:(1)2000—2018年黄土高原蒸散发年际变化率为4.47 mm/a,62.8%的区域蒸散发呈显著增加趋势,主要分布在山西、青海、陕西省北部地区;不同土地覆盖ET为森林>农田>草地>灌木。(2)植被显著增加是黄土高原ET变化的主导因子,其相对贡献率最大(32.1%);不同气象要素对黄土高原ET相对贡献率大小为降雨(14.6%)>饱和水汽压差(13.2%)>温度(12.4%)>日照时数(10.0%);非植被下垫面变化(水土保持工程措施等)对ET变化的影响作用不容忽视。(3)气象要素和增强型植被指数(enhanced vegetation index,EVI)对林草覆被ET影响作用>农田覆被ET,而非植被下垫面要素对农田覆被ET的影响作用较大。研究结果为黄土高原生态建设、水资源消耗恢复和水资源可持续性评价提供科学支撑。This study aimed to reveal the spatial-temporal variation of evapotranspiration(ET)in the loess Plateau during the past two decades and clarify the effects of climate and underlying surface changes on ET.Based on the data of 295 meteorological stations on the Loess Plateau,PML_V2 ET products and MOD13A1 EVI products,this study used trend analysis and multiple regression statistical methods to study the spatial-temporal variation characteristics of ET from 2000 to 2018,and the relative contributions of rainfall,temperature,sunshine duration,vapor pressure difference,vegetation and non-vegetation underlying surface were also quantitatively evaluated.The results showed that:(1)From 2000 to 2018,the annual change rate of ET on the Loess Plateau was 4.47 mm/a.The ET increased significantly in Shanxi,Qinghai and northern Shaanxi Provinces,accounting for 62.8% of the total area.The contribution of different land covers to ET was forest,farmland,grassland and shrub in descending order.(2)The significant increase of vegetation was the leading factor of ET changes in the Loess Plateau,and its relative contribution rate was the largest(32.1%).The relative contribution rates of different meteorological factors to ET from high to low were rainfall(14.6%),saturated vapor pressure difference(13.2%),temperature(12.4%)and sunshine duration(10.0%).The influence of non-vegetation underlying surface change(such as soil and water conservation engineering measures)on ET change could not be ignored.(3)The effects of meteorological factors and enhanced vegetation index on ET of forest and grass cover were greater than that of farmland cover,while non vegetation underlying surface elements had a greater impact on ET of farmland cover.The research results are expected to provide scientific support for water resources consumption,restoration and sustainability evaluation of ecological construction in the Loess Plateau.

关 键 词：蒸散发 气候变化 下垫面变化 黄土高原 

分 类 号：S161.4[农业科学—农业气象学]