Estimating the relationship between dam water level and surface water area for the Danjiangkou Reservoir using Landsat remote sensing images

摘要

The Danjiangkou Reservoir (DJKR) is the freshwater source for the Middle Route of the South-to-North Water Diversion Project (MRSNWDP) in China. It is important to characterize the dam water level (DWL) and surface water area (SWA) of the DJKR for the MRSNWDP. In this study, 81 phases of time-series Landsat images are used to estimate the SWA of the DJKR from 1993 to 2015. SWA and in situ-observed DWL data are employed to investigate the relationship between DWL and SWA for the DJKR. The results show that polynomial functions can describe this relationship, and quantitative assessment and qualitative analysis indicate that a cubic polynomial function is the optimal relationship between the DWL and SWA of the DJKR. The coefficient of determination (R-2) and root mean square error of the cubic polynomial function are 0.9879 and 0.6987, respectively. This relationship has implications for water resources management, flood control and environmental monitoring for the MRSNWDP.