Environmental effects of <i>Potamogeton crispus</i> population in Lake Xuanwu, Nanjing

Abstract

为了解玄武湖菹草种群的环境效应, 对玄武湖2006年春季水质变化、菹草区内外水质差异进行了监测, 并分析了2003-2006年春季水质监测资料, 结果表明:菹草区DO高于菹草-水交界区及开阔水域;从菹草区到菹草—水交界区、开阔水域TP、TN逐渐升高, TP均值分别为0.062、0.098、0.105mg/L, TN均值分别为1.674、2.202、2.412mg/L;与2003-2005年同期均值相比, 2006年3-5月份TP分别下降了15.4%、45%、43.3%, TN分别下降58.2%、43.9%、51.3%, SD保持在65cm以上;说明菹草在改善湖泊环境和净化水质方面有重要作用。最后提出了改善、维持玄武湖健康稳定水生生态系统的措施和建议。;To investigate the environmental effects of Potamogeton crispus population in Lake Xuanwu, water quality in and out Potamogeton crispus population area were monitored from January to June of 2006, and were compared from 2003 to 2006 in Lake Xuanwu. The results showed :1) From P. crispus population area to open water area, concentration of DO gradually decreased; 2)From u P. crispus population area”, “transition area” to “open water area”, concentration of TP and TN increased gradually. Average concentration of TP in those area were 0.062, 0.098 and 0.105 mg/L respectively, and average concentration of TN in those area were 1.674, 2.202 and 2.412mg/L respectively; 3) TP concentration from March to May in 2006 decreased by 15.4%, 45% and 43.3%, compared with the same months from 2003 to 2005; these told us that Potamogeton crispus population had vital roles in improving lake environment and purifying water quality. Finally, some suggestions about improving and maintaining stable aquatic ecosystems of Lake Xuanwu were put forward in the article.