Abstract:In light of the in-situ spectral measurement data and the synchronous hydrological sediment parameters from the survey in 2017 winter, the difference of spectral data obtained by two kinds of optical instruments: an ASD spectrometer and a Hypersas sea surface spectrometer in the high turbidity water of the Yangtze Estuary is discussed. The results show that the spectral values measured by the Hypersas spectrometer are higher than those measured by the ASD spectrometer on the whole. For the integration time of 34 ms, the difference between the two instruments is lowest. The average relative difference values in the typical bands of 412 nm, 443 nm, 490 nm, 510 nm, 531 nm, 555 nm, 670 nm and 750 nm are 22.70%, 18.73%, 15.01%, 14.07%, 13.05%, 11.93%, 9.58% and 9.85% respectively. By analyzing the correlation and fitting accuracy of the two sets of data and the suspended sediment concentration data measured, it is found that in the local mode, the accuracy of suspended sediment concentration modeled by the ASD spectrometer is (R2=0.78), which is higher than that modeled by the Hypersas spectrometer (R2=0.67).