天津市内水体叶绿素a变化及影响环境因子分析

Changes of Chlorophyll-a Concentration and Its Relationship with Environmental Factors in the Tianjin Water Body

监测了2013年3月到12月天津市内7个点位的水质变化情况,分析了叶绿素a(Chl-a)质量浓度的时空变化特征和主要环境因子的相关关系.结果表明,叶绿素a(Chl-a)质量浓度夏季最高,秋冬季次之,春季最低.空间分布上海河、南运河、津河叶绿素a质量浓度依次升高,湖泊中叶绿素a质量浓度相对河流较低.叶绿素a(Chl-a)质量浓度与水温呈显著正相关关系,与p H、CODMn呈极显著正相关关系,与溶解氧(DO)呈显著负相关关系.lg(Chl-a)与lg(TP)呈极显著正相关关系,与lg(TN),lg(TN/TP)呈极显著负相关关系,叶绿素a(Chl-a)质量浓度与氨氮不存在明显的相关关系.这表明磷是天津河湖水体富营养化的限制性因子.

The authors of this paper monitored water quality change at seven sites in Tianjin from March to December in 2013 to analyze the temporal and spatial variation of the mass concentration of chlorophyll-a in the water and its correlation with environmental factors. The results indicated an obvious temporal and spatial variation of chlorophyll-a concentration.The concentration of chlorophyll-a was highest in summer, medium in autumn and winter, lowest in spring.The chlorophyll-a concentration in the key rivers was higher than in the artificial lakes. The chlorophyll-a concentration increased from Haihe River to South Canal and then to Jinhe. Chlorophyll-a concentration in the lake water is relatively lower than in the river water. The relation between Chlorophyll a（Chl-a）concentration and the water temperature turned to be a significant positive correlation;the relation among Chlorophyll-a and p H,CODMn was a highly significant positive correlation. The relation between Chlorophyll-a and dissolved oxygen（DO）tuned to be significantly negatively correlated. The relation between lg（chl-a）and lg（TP）was a highly significant positive correlation. The relation between lg（TN）and lg（TN/TP）showed a significant negative correlation. Chlorophyll a（Chl-a）concentration and NH3-N had no obvious correlation. This indicates that phosphorus is a limiting factor of eutrophication in the rivers and lakes in Tianjin.