基于卫星观测及水质动力模型的感潮河流水质监测分析

The advantages of continuous space-time coverage by satellite observations and high time resolution by water quality and hydrodynamic models were complemented and utilized in this study to analyze the water quality change of the tidal river. Based on the in-situ data, the chlorophyll a concentration of the tidal river-Huangpu River was quantitatively retrieved by Lansat8/OLI satellite data. The root mean square error between the inversion data and the measured data was 4.82 mg·m⁻³, and the determination coefficient R² was 0.68. Based on the Delft3D model, the water quality parameters of the Huangpu River Dissolved, i.e. Oxygen (DO), Ammonia Nitrogen (NH₃-N) and Potassium Permanganate Index (COD_Mn), were simulated. Results showed that the root mean square error of the simulated water level by the hydrodynamic module was 0.22 m, and the verified root mean square errors of DO, NH₃-N, and COD_Mn were 0.53 mg·L⁻¹, 0.16 mg·L⁻¹, 0.27 mg·L⁻¹, respectively. The correlation between chlorophyll a concentration and water quality parameters of Huangpu River from August 2013 to July 2014 was further analyzed. It was found that with the increase of chlorophyll a concentration in Huangpu River, DO and NH₃-N increased while COD_Mn decreased. Based on the correlation between chlorophyll-a concentration and water quality parameters, the DO, NH₃-N, and COD_Mn of Huangpu River were retrieved by using Lansat8/OLI satellite data. It was found that the water quality parameter values varied greatly with seasons for tidal river. This study demonstrated the great significance to combine satellite observation with dynamic model for water quality analysis of tidal rivers.