STUDY ON REMOTE SENSING MODE OF CHEMICAL OXYGEN DEMAND IN THE PEARL RIVER ESTUARY

摘要

Chemical oxygen demand (COD) is a comprehensive assessment index of water pollution. It is the basis to protect water source and prevent pollution by obtaining the data of COD and control the change of COD concentration in time. In this paper, the study area is the Pearl River Estuary. The water quality of the Pearl River Estuary is becoming worse and worse due to the marine environment is constantly destroyed. To gain a better understanding of water quality in the Pearl River Estuary, we obtained the experimental data in-situ including the absorption coefficient of CDOM ( Colored Dissolved Organic Matter ) and COD concentration at 28 stations in the region of the Pearl River Estuary in November 2013 and February 2014. Analyzing the quantitative relationship between COD concentration and the absorption coefficient of CDOM through exploring the mechanism of the influence of COD in water on the spectral absorption features of CDOM. To establish an empirical model for the inversion of the concentration of COD based on Landsat8/OLI images data. The model was applied in the region of the Pearl River Estuary. The correlation coefficient value of the inversion of the constituent is over 0.8. The establishment of the mode based on remote sensing lays a solid foundation for the inversion of the water quality parameters and the assessment of organic pollution in water body.