| When we simulated backscattering coefficients(bbp) using quasi-analytical algorithm and optical closure theory, it was found that the position of reference wavelength (λ0) had great impact on final results. In order to identify influence factors of the optimum λ0, datasets of Lake Taihu, Lake Chaohu and Lake Dianchi were used. After simulating of bbp, the relationship between optimum λ0 and associated water quality parameters were analyzed. Meanwhile, power functions were utilized to model bbp spectra, and spectral slope parameters of Lake Taihu, Lake Chaohu and Lake Dianchi were 2.643±0.317, 2.719±0.242, 1.638±0.534,respectively. The results indicate that: ①When the whole lakes are taken as objects of study, the λ0should be changed to longer wavelength with the increasing of total suspended particle matter concentration (cSPM), suspended organic particle matter concentration (cSPOM) and chlorophyll a concentration (cCHL),the optimum location of λ0 of Lake Taihu is 695 nm, Lake Chaohu is 720 nm and Lake Dianchi is 730 nm;②When the samples in lakes are taken as objects of study, the influence factors are different due to the complexity of optical properties of inland waters. But it is to be noted that, cSPM is a key factor in common. Besides, the regularity mentioned above should be weakened with high cCHL. ③ The relationship between bbp and cSPM is much stronger in the waters with suspended particles dominated by inorganic particles, in Lake Taihu, for example, relationship between these two variables is strong with R2=0.852. |
