Spectral absorption characteristics of algae and discrimination of the absorption spectrum of mixed algae
藻类的光谱吸收特征及其混合藻吸收系数的分离

The absorption spectra of Microcystis aeruginosa, Scenedesmus obliquus, Chlorella pyrenoidosa, Selenostrum capricornutum and Melosira granulate var angustissima were taken and compared to the counts obtained by the quantitative filter technique. The normalized absorption spectra were then compared. The normalized absorption spectra were seldom variational in different growth period. The species differences of pigment and the ratio among different pigment species account for the variance of absorption spectra and are also the primary reason for species succession of phytoplankton in waters. Cyanobacteria have a peak at 620 nm, which is propitious to compete for light. The short-wave advantage of Melosira granulate var angustissima was waken by the colored dissolved organic matter (CDOM) and non-algae particles and the absorption peak at 630 nm is not strong, which is why Melosira granulate var angustissim is less able to compete for light. For green algae, the absorption shoulder at 655 nm helps them compete for light. The spectral absorption of mixed algae was successfully partitioned from the normalized absorption spectrum. This research is relevant to research on the mechanisms of cyanobacteria blooms, species succession of phytoplankton in natural waters, and remote sensing for case 2 waters.