地表水热通量的准确估算对全球环境变化、流域水资源管理以及农业灌溉规划等具有十分重要的科学意义与应用价值。水热通量主要受气象条件和下垫面因素的影响，而水体的扩张与退缩同时影响其周边的微气象特征和下垫面特性，进而影响周边区域的水热通量。本文利用遥感数据、怀来试验站大孔径闪烁仪、涡动相关仪和自动气象站的观测资料，结合气候学足迹模型，分析了2013-2017年官厅水库的面积变化及其周边区域水热通量、微气象特征变化，对比了与水库不同距离测点的水热通量与微气象特征的变化，并探讨了相关原因，得到以下结论： （1）2013-2017年官厅水库的面积逐年增加，观测点与水库距离随之减小。其中官厅水库的面积呈现春季扩张，夏季缩小和冬季再次扩张的季节变化特征。 （2）官厅水库的逐年扩张对其周边地区微气象的影响主要体现在风速和深层土壤水分的升高，对水热通量的影响主要体现在蒸散发的逐年增加，且其影响在非生长季和生长季是不同的。在非生长季，官厅水库的扩张引起的大孔径闪烁仪观测源区内水体比例的变化，使非生长季蒸散发逐年增加；而在生长季，官厅水库的进退通过改变深层土壤水分从而间接影响区域蒸散发量。此外，随着水库扩张，区域可利用能量再分配逐渐趋向潜热通量。 （3）距离水库较近的地区受到水库扩张的影响更大，其蒸散发的年际变化和季节变化更加明显。非生长季时水面比例的增加会直接导致距离水库较近地区的蒸散发量有明显的升高，而距离水库较远的地区变化不大；在生长季时，与水库较近的地区，其深层土壤水分有更高的增长率。

Accurate estimation of terrestrial water/energy flux is crucial to water resources sustainability with climate change, watershed management and irrigation planning. Water/energy flux is mainly controlled by meteorological conditions and the underlying land cover. On the other hand, the expansion and shrinkage of water body alter meteorological characteristics and the underlying land cover, which in turn affect water/energy flux in the surrounding area. In this study, the area changes of Guanting Reservoir during 2013-2017 was analyzed using satellite remote sensing data. Based on the measurements of large aperture scintillometer (LAS), eddy covariance system (EC) and automatic weather station (AWS), combined with the footprint model of LAS and EC, the variations of water/energy flux and the characteristics of micrometeorology in the surrounding area were analyzed, and the changes within different distances from the reservoir were compared. Major conclusions were summarized as follows: 1. The area of Guanting Reservoir increased year by year in 2013-2017; while the distance between observation points and the reservoir decreased. The area of Guanting Reservoir also exhibited a seasonal variation pattern of expanding in spring, shrinking in summer and expanding again in winter. 2. The effect of the expansion of Guanting Reservoir on the meteorological characteristics of the surrounding area mainly reflected as an increasing of wind speed and soil moisture. The expansion also caused an increase in evapotranspiration (ET) year by year, which, however, showed different characteristics in the non-growing season and the growing season. In the non-growing season, the expansion of the Guanting Reservoir caused an increase in the proportion of the water body in the source, which led to the increase of ET. During the growing season, the reservoir was indirectly affected ET due to the change of the soil moisture. In addition, with the expansion of the reservoir, the regional energy distribution gradually transformed to latent heat flux. 3. In areas closer to the reservoir, the water/energy flux and micrometeorology characteristics were more influenced by reservoir expansion. During the non-growing season, in areas nearer to the reservoir, the increase in the proportion of the water body would directly lead to an increase in ET. In the growing season, the soil moisture had a higher increase rate in the area closer to the reservoir.