某城市湖泊中磷的循环特征及富营养化发生潜势

通过对浙江省临海市东湖水体磷元素的输入与输出途径与通量、磷元素在湖泊环境中的循环特征以及磷循环对水温上升的响应分析,并基于对该水体从2000年开始隔年进行各参数的观测,表明2000年以来磷输入年平均增量为0.007～0.009mg/L,水中叶绿素a平均年增0.14～0.56μg/L,透明度年平均下降0.38～0.49m,溶解氧年平均下降0.21～0.71mg/L.并依此建立了反映湖泊富营养化发生潜势的这些主要代表性参数与湖水中总磷含量之间的相关关系,揭示了可以通过从磷物质单因子的变化预测所引起的其它因子变化之间的关系来综合判断湖泊的营养状态,从而为减少湖泊富营养化的发生、提高湖泊水质提供科学依据.

Cycling Characteristics of Phosphorus in a Urban Lake and Its Eutrophication Potentiality

Input and output pathway, fluxes, characteristics and temperature-increasing responses of phosphorus cycling in the East Lake located at the centre of Linhai City, Zhejiang Province, China were analyzed. On the basis of the annual field observation on the lake, it was indicated that chlorophyll a in water was being increased at the average rate of 0.14-0.56 microg/L, the transparence in water was being decreased at the average rate of 0.38-0.49 m, and dissolved oxygen in water was being reduced at the average rate of 0.21-0.71 mg/L. Relationships between the representative measurable parameters which can reflect the eutrophication potentiality of a lake and total phosphorus (TP) in water were set up, thus revealing that a change of phosphorus in lake water can be used to comprehensively judge the nutrition situation of a lake through forecasting changes in other factors and their relationships. This work can thus provide a scientific basis for decreasing eutrophication and improving water quality of lakes.