杭州城区河道水体及底泥污染指标的相关性研究

Study on Correlation between Pollutants from Water Body and Sediment of Rivers in Urban Areas of Hangzhou

以杭州城区六条代表性河道水体及底泥污染物实际监测数据为基础,分析研究了pH、营养盐、耗氧类指标、有机物和重金属等污染指标之间的相关关系,为杭州城市水环境的综合治理提供参考。结果表明:(1)河道水体中TN、TP和NH3-N呈显著的正相关,COD Mn和BOD5相关性极显著,说明污染具有同源性;(2)河道底泥中的有机质、全磷与全氮有较好的相关性,有机质与四种重金属的相关性由大到小的顺序依次为Cd>Pb>Zn>Cu,四种重金属之间Pb与Cd和Zn相关性显著;(3)河道中底泥相对比较稳定,大部分时期底泥中的营养盐和上覆水体中的营养盐没有相关性,底泥对上覆水体的影响较小。

Based on the data of pollutants collected from both the water body and the sediment of the six representative rivers in urban areas of Hangzhou, a number of physical and chemical parameters, including pH, eutrophication index, oxygen demand index, organic substances and heavy metals, were monitored. The correlation analysis of them will provide useful information for the comprehensive management of the municipal aquatic environment. The results indicated that： 1 ） positive correlation was proved for total nitrogen （TN）, total phosphorus （TP） and ammonia - nitrogen （ NH3 - N）, and similar correlation was determined for chemical oxygen demand for manganese（ CODM. ） and biochemical oxygen demand over a 5 -day period（ BOI）~ ）. It showed that Pollution had a homology; 2） organic matters in the sediment and total nitrogen（TN） were highly correlated; however, total phosphorus（TP） and organic matters were fairly correlated. The level of correlation between organic matters and each heavy met al, from high to low, would be Cd, Pb, Zn, and Cu, and, among these heavy metals, Pb, Cd, and Zn were relatively more cor related ;3） the sediment remains relatively stable at the bottom of the river, most of time the nutrient load from the deposit at the bottom did not interact with that in the upper water body, which means the nutrient load in the sediment had little effect on the nu trient dissolved in the upper water.