中文摘要：

为研究崇明岛“闸控型”河网水体富营养化特征及其与环境因子的相互作用，以2010年各季节崇明岛河网水质数据为基础，探讨了环境因子与藻类的变化规律及其相互作用机制．结果表明：崇明岛河网水环境中营养盐水平较高，氮污染尤为严重．长江引水进人岛内河网水环境后，营养盐（除SiO3-Si）、Chl．a含量和营养状态都出现了明显的升高．与长江引水相比，河网内藻类群落Chl．a贡献比例的变化主要表现为硅藻比例的下降以及蓝藻和绿藻比例的上升．尽管水温、pH、浊度以及营养盐中的TN、TP、NO3^--N、DOC的变化均与Chl．a含量显著相关，但藻类群落对环境因子的响应关系存在较大差异．蓝藻的增加主要与水温和TP含量的升高有关；绿藻与TN、NO3^--N的关系最为密切；硅藻的变化只与浊度存在明显正相关，营养盐并不是硅藻生长的促进因子．

英文摘要：

In order to understand eutrophication and its relationships with environmental factors in gate-controlled river network system of Chongming Island, variations of environmental factors and algae as well as their interaction mechanisms were studied based on seasonal water quality data of the river network. Results indicated that the concentrations of nutrients in the river network were high and nitrogen pollution was particularly serious. The contents of nutrients, Chl. a and trophic state increased significantly after the Yangtze River water entered into the river network. The proportion of diatom decreased with increasing proportions of cyanobacteria and chlorophyta in the river network comparing with the water of the Yangtze River. Although water temperature, pH, turbidity, TN, TP, NO3- -N and DOC had significant correlations with algal biomass, the relationships between algal community and environmental factors were different. Water temperature and TP were the main factors of promoting growth of cyanobacteria ; chlorophyta was closely related to TN and NO3- -N ; and diatom was only related to the turbidity while nutrients were not promoting factors of diatom.