【摘要】 位于长江源头的青海省属于干旱半干旱地区,全面系统分析区域内多年地表蒸散的时空分布变化及其相关主导气象因子的贡献,对于全省地表水量平衡调节、水资源科学配置、生态环境治理以及旱涝灾害监测有着重要的作用。基于MOD16数据集(MODIS地表蒸散发月序列产品),采用年际趋势分析法分析了青海省2000-2014年的地表蒸散量时空变化;同时,结合多年降水量和气温数据,利用奇异值分解(SVD)模型,分析了地表蒸散量和气温、降水量之间的相关性。结果表明:青海省多年平均地表蒸散量在空间上呈现东南多,并向西北逐渐减少的趋势,这种空间分布规律主要受降水量由东南向西北逐渐递减的空间分布规律决定;地表蒸散量与气温、降水的平均相关系数分别为0.071和0.201,同时蒸散与气温、降水的相关性在空间分布上基本一致; SVD分析结果显示地表蒸散量与降水量存在明显的相关性,而与气温的相关性较弱。更多还原

【Abstract】 Qinghai Province, located in the sources of the Yangtze River and Yellow River, belongs to the arid and semi-arid regions. It plays an important role in regulating the balance of surface water, allocating water resources scientifically, harnessing the ecological environment and monitoring drought and flood disasters by systematically analyzing the spatial and temporal variations of surface evapotranspiration and the contributions of related dominant meteorological factors at the provincial level. In this article, the spatial and temporal variations of surface evapotranspiration in Qinghai Province during 2000-2014 are analyzed based on the MOD16 dataset(MODIS surface evapotranspiration monthly series products) by interannual trend analysis method, and explored the correlation between evapotranspiration and air temperature and precipitation by singular value decomposition(SVD) model with the data of precipitation and air temperature. The results show that:(1) The annual average evapotranspiration of Qinghai Province has a high value in southeast and gradually decreases to the northwest which was determined by the spatial distribution of precipitation.(2) The average correlation coefficients between evapotranspiration and air temperature and precipitation are 0.071 and 0.201, respectively. SVD analysis results show a significant correlation between evapotranspiration and precipitation, but the correlation between evapotranspiration and air temperature not so significant.更多还原