Abstract: In an attempt to explore the effect of Gaofen-1 (GF-1) satellite on remote sensing inversion of river water quality, the remote sensing estimation models of Chlorophyll-a and total suspended matter concentration were constructed to estimate the water quality in Hangzhou segment of Qiantang River by simulating the WFV bands by in situ spectral reflectance based on the GF-1/WFV data with 16 m resolution and the ground measured data. Results prove that the quadratic polynomial model based on the reflectance difference of B1 and B3 band (B1-B3) can be used to estimate the Chlorophyll-a concentration with R²=0.83 and RMSE=0.74 μg/L; the quadratic polynomial model based on the B3 band reflectance can be used to estimate the total suspended matter concentration with R²=0.92 and RMSE=1 mg/L. The models were applied to quasi-synchronous GF-1/WFV data, which well reflected the spatial distribution of Chlorophyll-a and total suspended matter concentration in the low-tidal Qiantang River. This research is a useful exploratory work to monitor the water color parameters of Qiantang River by the GF-1 satellite data, and the research methods and results offer reference for the study of water color remote sensing in other river basins.

Key words: chlorophyll-a concentration, total suspended matter concentration, Qiantang River, GF-1 satellite, remote sensing model