灌区蒸散发遥感反演及其时空变化特征分析——以漳河灌区为例

准确反演区域尺度的蒸散发对于水资源循环、气候变化、科学灌溉及干旱与洪涝监测等方面的研究具有重要的科学意义，本文以漳河灌区为典型案例，构建了遥感蒸散发的SEBS模型，验证了其精度，分析了其时空规律。结果表明：①2009—2018年钟祥、荆门、团林站点的（蒸散发） ET观测值与模拟值的平均相关系数分别为0.86、0.84和0.83，RMSE平均值分别为0.61、0.67和0.62 mm/d。年际间的ET观测值与模拟值变化幅度均小于10%，相关系数范围为0.7～0.9，RMSE范围为0.4～0.8 mm/d，标准差比率范围为0.8～1.5。②研究区2009—2018年ET的平均值为427.34 mm，整体呈上升趋势。③年尺度、季尺度和月尺度ET与气温和降水在时间序列上均有较好的一致性。多时间尺度ET均呈东北和西南部高、西部低的空间分布特征。研究结果能够较好地呈现ET的高时空异质特征和年际间空间差异，本文将为漳河灌区水资源开发管理和科学灌溉提供科学依据。

Analysis of evapotranspiration estimation and its spatial-temporal characteristics: taking Zhanghe irrigation district as an example

Regional scale accurate inversion of evaporation for water cycle, climate change, scientific irriga-tion and drought and flood monitoring research has important scientific significance, this article taka Zhanghe irrigation district as typical irrigation area, builds the SEBS model of remote sensing evaporation, verifies the accuracy of re-mote sensing evaporation, the temporal and spatial law of evaporation is analyzed. The results show that:① the average correlation coefficients between ET observation values and simulated values at zhongxiang, jingmen and tuanlin stations from 2009 to 2018 are 0.86, 0.84 and 0.83 respectively, and RMSE valu-es are 0.61, 0.67 and 0.62 mm/d respectively. The interannual variation of ET observed and simulated values is less than 10%, the correlation coefficient ranges from 0.7 to 0.9, RMSE ranges from 0.4 to 0.8 mm/d, and standard deviation ratio ranges from 0.8 to 1.5. ② The average value of ET in the study area from 2009 to 2018 is 427.34 mm, and ET shows an overall upward trend.③ The time series of ET and precipitation at annual, seasonal and monthly scales are consistent. ET is higher in northeast and southwest and lower in west at multiple time scales. The research results can better present the high spatio-temporal heterogeneity of ET and the spatial differences of ET between years. This study will provide scientific basis for the development and management of water resources and scientific irrigation in Zhanghe irrigation district.