衡水湖湿地营养化状况健康评估及原因分析

Health Assessment and Cause Analysis of Nutritional Status of Hengshui Lake Wetland

衡水湖是典型的平原浅水型湖泊,一直受营养化问题困扰,特选取衡水湖近岸区、开阔区、芦苇区、蒲草区等不同区域水质资料分析其营养化状态,运用河湖健康评估分级标准赋予其健康状况描述,找出主要影响因素,有针对性地提出治理建议。衡水湖营养状态健康评估显示:东湖大湖为亚健康,主要影响因素为透明度、总氮;小湖为不健康,主要影响因素为透明度、总氮及高锰酸盐指数。自2016年起,在总体营养状态趋于好转的情形下,透明度的影响逐年增加,甚至在2021年超过了总氮,成为了主要影响因素。除受湖体自身影响之外,外来引水水质同样影响较大。

Hengshui Lake is a typical plain shallow water lake,which has been plagued by nutrient problems.The water quality data of Hengshui Lake in different areas,such as the coastal area,open area,reed-work area and cattail area,are selected to analyze its nutrient status.The river and lake health assessment grading standard is used to describe its health status in order to find the main influencing factors and propose targeted management suggestions.The health assessment of the nutrient status of Hengshui Lake indicates that the nutrient status of the large lake of the east lake in Hengshui Lake is sub-healthy,and its main influencing factors are diaphaneity and total nitrogen;the nutrient status of the small lake is unhealthy,and its main influencing factors are diaphaneity,total nitrogen and the index of potassium permanganate.Since 2016,when the overall nutrient status tends to improve,the impact of diaphaneity has increased year by year,and even exceeded total nitrogen in 2021,becoming the main influencing factor.Besides the impact of the lake itself,the quality of the external diversion water also has a greater impact.