Effect of Arsenic Species on the Growth and Chlorophyll Fluorescence Characteristics of Scenedesmus obliquus

The effects of different concentrations of As(III) and As(Ⅴ) on the growth and chlorophyll fluorescence characteristics of Scenedesmus obliquus were investigated.Under the condition of high concentration(≥500 μM/L),the inhibition of As(III) on growth rate of S.obliquus is greater than As(V).The influence of arsenic on the content of chlorophyll a showed that,chlorophyll a content of S.obliquus showed a decreasing tendency with the increase of arsenic concentration.the effect between two arsenic species showed that the chlorophyll a is more sensitive to As(Ⅲ) than As(V).The correlation analysis showed that the main chlorophyll fluorescence parameters(F v / F m,Yield,ETR max) were negatively correlated with the concentrations of two species arsenic.The study showed that the inhibitory effect of arsenic on S.obliquus is consistent with the inhibition on photosynthetic system,and As(III) inhibitory effect on chlorophyll fluorescence than As(Ⅴ).