Abstract:

In order to explore the effect of hydrological regimes on algae bloom and succession,3 species from different phylum,Microcystis aeruginosa (Cyanophyta),Chlorella vulga (Chlorophyta) and Stephanodiscus hantzschii (Bacillariophyta),were used in present study to compare the effects of turbulent conditions (0 and 38 m/s) on the phosphorus (P) uptake kinetics in different bloomforming algae.The growth rates of three algae were predicted under standing and turbulent conditions according to their P uptake kinetic parameters.Our result showed that hydrodynamic can significantly affect the growth of algae by changing the P uptake rates and hydrodynamic impacted different algae differently.Compared to standing condition,the P uptake rates and P affinity of M.aeruginosa and S.hantzschii under turbulence declined markedly（p<005）,however,the P uptake rates and P affinity of C.vulga increased significantly（p<005).Based on Monod model,the turbulence could inhibit the growth of M.aeruginosa and S.hantzschii in different degrees but boost the growth of C.vulga.Our results reveal that the difference characteristic of phosphorus uptake kinetics in three bloomforming algae under turbulent and standing conditions might result in distribution and succession of algae in rivers.With the increase of P concentration and decrease of flowing rate in rivers,the risk of blooms from diatoms to cyanobacteria will be increased.〖HJ1〗〖HJ〗