Spectral variability of particulate backscattering ratio in the Daya Bay
大亚湾水体后向散射比率的光谱变化

Variability of particulate backscattering ratio and its interpretation were examined using in-situ measurements performed during May 2007 in the Daya Bay. The results indicated that the particulate backscattering ratio values range between 0.004 and 0.0245, with a mean value of 0.0082±0.0032. There was some spectral dependence of the particulate backscattering ratio, and less than 15% variability between wavelengths was estimated. A global decreasing of particulate backscattering ratio with increasing chlorophyll concentration was visible, and the low backscattering ratios were observed in water with high chlorophyll concentration. Particle-size distribution slope was the main factor controlling the variability of particles backscattering ratio: The particle backscattering ratio increased with particle-size distribution slope. Average particle refractive index was another influencing factor. With similar particle-size distribution, the amount of non-pigment material relative to phytoplankton that was characterized by the variability of refractive index had a strong effect on particulate backscattering ratio.