内陆湖泊主要藻种散射特性

通过室内培养4种主要淡水藻种--铜绿微囊藻(Microcystis aeruginosa)、普通小球藻(Chlorella vulgaris)、梅尼小环藻(Cyclotella meneghiniana)以及卵形隐藻(Cryptomonas ovata), 测定其散射和后向散射特征参数、用单位叶绿素a浓度的散射值和后向散射值来表征4种藻的散射和后向散射能力。结果表明, 铜绿微囊藻散射和后向散射能力最强, 其次为梅尼小环藻, 普通小球藻的能力最弱。通过计算后向散射概率, 显示铜绿微囊藻和梅尼小环藻的后向散射概率值较高, 普通小球藻和卵形隐藻的后向散射概率值较低。后向散射特性影响因子分析显示, 影响后向散射值的主要因素有叶绿素a浓度及藻蓝蛋白色素比例。当叶绿素a浓度不断增加时, 其后向散射值不断增大; 当藻类所含叶绿素a比重不断上升时, 其后向散射值也不断增大。而细胞粒径与后向散射值之间未表现出很好的相关性。因此, 通过单位叶绿素a散射和后向散射概率特征可以辨别出藻细胞形态较为接近的铜绿微囊藻和普通小球藻。

Scattering and Backscattering Properties of Main Fresh Water Alga Species

Scattering and backscattering properties were measured for 4 main fresh water alga species cultured in the laboratory: Microcystis aeruginosa, Chlorella vulgaris, Cyclotella meneghiniana and Cryptomonas ovata. Chlorophyll a-specific scattering and backscattering were used to represent scattering ability. M. aeruginosa had the strongest scattering and backscattering ability, followed by C. meneghiniana, and C. vulgaris had the weakest. M. aeruginosa and C. meneghiniana showed greater backscattering ability than C. vulgaris and C. ovata. The main factor affecting backscattering was the ratio of chlorophyll a to phycocyanin content. Backscattering coefficient varied with chlorophyll a content and chlorophyll a proportion to total pigment. We found a good correlation between cell size and backscattering coefficient.