基于Landsat8与GEOEYE-1数据融合的天山北坡县域蒸散量计算——以呼图壁县为例

基于Landsat 8与GEOEYE-1遥感数据,使用多尺度遥感方法,以新疆呼图壁县为例,利用SEBS模型计算天山北坡县域蒸散量,服务小流域和县域为管理单元的最严格水资源管理。针对军塘湖河流域耕地、呼图壁河流域耕地和北部荒漠-绿洲过渡带,应用2 m分辨率GEOEYE-1影像计算得NDVI和基于NDVI-T_R法模拟的地表温度。将获得的地表温度和NDVI作为SEBS模型的重要参数计算地表蒸散量,采用自制小型蒸渗仪观测数据对估算结果进行评估。结果表明:在使用中分辨率影像Landsat 8估算地表蒸散量过程中加入GEOEYE-1反演的个别参数,大部分估算结果更加接近自制微型蒸渗仪测定值,估算绝对误差最大值出现在裸地,为28.5%,远低于使用Landsat 8影像的54.8%,说明高分影像的参与有助于提高模型估算效率。

Evapotranspiration Estimation at Hutubi County in Northern Slope of the TianShan Mountains Using Data Fusion of Geoeye-1 and Landsat 8

Using the Landsat 8 data (30 m) and high resolution Geoeye-1 data (2 m), combined with multi scale remote sensing method to estimate evapotranspiration at Hutubi County in Northern Slope of the TianShan Mountains. In some areas such as arable land on Hutubi river basin, arable land on Juntanghu river basin and oasis-desert ecotone, we take Geoeye-1 remote sensing image to compute NDVI and land surface temperature then input them to the SEBS model. The significance of the study is the influence of data fusion on evapotranspiration calculation results with two kinds of sensor data. The results show that adding some parameters which come from Geoeye-1 make the estimated value closer to measured values which come from small lysimeter. The maximum absolute error appears in the bare ground in 28.5%, still below the 54.8% only using Landsat 8 data, indicating that participation of high resolution images helps to improve the efficiency of the model.