苏州河浮游植物群落恢复的生境条件研究

Research on the habitat condition of phytoplankton community’s restoration in Suzhou Creek

于2005年4月至2006年5月期问对苏州河浮游植物群落及理化因子进行研究，分析了苏州河浮游植物现状及水质现状，并分析两者之间的关系，得出水温、总磷、总氮、CODcr等理化因子对浮游植物群落有显著影响，且其影响均存在临界值，分别为水温15℃、总磷0．6mg·L-1、总氮10mg·L-1、CODcr20mg·L-1。即在苏州河的浮游植物群落恢复中，当理化因子小于其相对浮游植物群落的临界值时，小球藻的出现频率低、密度百分比低，梅尼小环藻出现频率高、密度百分比高：而当理化因子大于其相对浮游植物群落的临界值时，小球藻的出现频率高，密度百分比高，梅尼小环藻出现频率低，密度百分比低。因此在对苏州河进行生态恢复时，应考虑到各理化因子对浮游植物影响的临界值，综合权衡各方面因素，确定水质恢复应达到的目标。

A research on phytoplankton community and physical and chemical factors were conducted from Apr. 2005 to May 2006 in Suzhou Creek, the phytoplankton community status and the water quality status were analyzed, and the relationship between phytoplankton and water quality was also analyzed, the results showed that the water temperature, TP, TN, CODer had significant impact on phytoplankton community and the impact had thresholds which were as follows： water temperature： 15 ℃,TP：0.6 mgoL.-1, TN：10 mgoL~, CODer：20 mg.-1. In the ecological restoration of Suzhou Creek, when the physical and chemical factors were lower than the thresholds, the appearance frequency and density percentage of Chlorella were low, while the appearance frequency and density percentage of Cyclotella meneghiniana were high; when the physical and chemical factors were higher than the thresholds, the appearance frequency and density percentage of Chlorella were high, while the appearance frequency and density percentage of Cyclotella meneghiniana were low. So the thresholds of physical and chemical factors impacting on phytoplankton should be considered to restore the water quality in Suzhou Creek.