Reservoir water bodies extraction optimization approach based on DEM and inundation frequency
LIU Shiyan1， CAI Xiaobin1
(1.University of Chinese Academy of Science， Beijing 100049，China； 2.Key Laboratory for Environment and Disaster Monitory and Evaluation in Hubei，Innovation Academy for Precision Measurement Science and Technology， Wuhan 430071， China)
Abstract：Due to the invalid surface image elements caused by clouds and mountain shadows， it's difficult to obtain high-precision dynamic monitoring result of reservoir water bodies using remote sensing images. The Otsu method， combined with DEM and inundation frequency as constraints， is introduced as DF optimization approach to solve the problem. The modified normalized difference water index (MNDWI) is calculated from USGS Landsat 5/7/8 Level 2， Collection 2， Tier 1 satellite image datasets. Then the Otsu method is used to extract the preliminary inundation results of the reservoir water bodies. The mountain shadows or other independent patches far away from the reservoirs are removed through DEM threshold and inundation frequency constraints. The globally distributed nine reservoirs are used to verify the optimization approach. The results show that the optimization approach is able to effectively eliminate the reservoir water body misclassification. The overall extraction accuracy， is significantly improved from 82.67% of the results directly derived from the JRC MWH datasets to 95.67% of our DF approach. The average of water area root mean square errors (RMSE) of nine reservoirs is reduced by 30.55% compared with the automatic correction results by using the simulated area from the linear level-area regression model. The DF optimization approach would easily be used in the GEE platform to generate the long-term time reservoir water body dynamics， providing continuous reservoir surface area data as the fundaments to the reservoir-related study on national or global scales.
刘诗燕,蔡晓斌,. 结合DEM与淹没频率的水库水体动态遥感提取优化方法[J]. 华中师范大学学报(自然科学版), 2022, 56(3): 523-531.
LIU Shiyan,CAI Xiaobin. Reservoir water bodies extraction optimization approach based on DEM and inundation frequency. journal1, 2022, 56(3): 523-531.
2022, Vol. 56 
