银湖夏季叶绿素a与水质因子的相关分析及富营养化评价

Correlation Analysis between Chlorophylla and Water Quality in Yin Lake in Summer and Its Eutrophication Evaluation

依据2009年5~7月对银湖水质的连续调查和监测数据,分析叶绿素a含量的时间变化特征,探讨叶绿素a与水质因子的相关关系,并应用修正的卡尔森营养状态指数对银湖水质进行分析评价。研究表明,叶绿素a具有明显的时间变化特征,5月叶绿素a的含量明显大于7月,Ⅲ区靠近垂钓区叶绿素a含量最高;基于叶绿素a、透明度和总磷等参数,依据修正的卡尔森营养状态指数公式,计算得出银湖水质在夏季处于富营养化状态;相关分析表明,叶绿素a与高锰酸盐指数、总氮量呈极显著正相关,而与透明度显著负相关,与水温、溶解氧、pH值、总有机碳量呈正相关,而与总磷量呈负相关关系。

The correlation between chlorophyll-a and other environmental factors was analyzed,based on the continuous monitoring data in Yin Lake from May to July in 2009,and modified Carlson trophic state index was also used to assess the water quality of Yin Lake.The results showed that the chlorophyll-a had obvious temporal change characteristics.The content of chlorophyll-a in May was higher than that in July obviously,and that in the fishing region in area Ⅲ was the highest.Based on chlorophyll-a,transparence and total P and other parameters,according to modified Carlson trophic state index（TSIM53）,an conclusion was drawn that the whole lake in summer was in eutrophic state.Significantly positive correlations were found between chlorophyll-a concentration and permanganate indexes,total nitrogen,but significantly negative correlation with transparency.At the same time positive correlation was found between chlorophyll-a and water temperature,pH,dissolved oxygen,total organic carbon.However,negative logarithmic correlation was found between chlorophyll-a and total phosphorus.