闽江下游水质变化趋势分析

根据闽江水口水库运行以来1993—2011年闽江下游省控监测断面的主要水质数据,应用季节性肯达尔检验法对省控断面的水质指标变化趋势进行分析,并应用偏相关分析法对竹岐、魁岐断面的夏秋季(6—11月)DO降低的原因进行分析。结果表明:近十几年来,闽江下游水质总体较好,上段水口水库和下段的入海口河道水质变化不大,但邻近人口聚集地的河道水质状况呈下降趋势,其中竹岐、魁岐断面的夏秋季DO降低最为明显;竹岐和魁岐断面的夏秋季DO分别与竹岐断面径流量成极显著性正相关,偏相关系数分别为0.749和0.866,分别与福州市GDP成极显著性负相关,偏相关系数分别为-0.739和-0.875。

Analysis of change trend of water quality in Minjiang River downstream

According to the water quality data of the provincial monitoring sections of the Minjiang River downstream from 1993 to 2011, the seasonal Kendall method was used to analyze the trend of the water quality indices. The cause of the decrease of DO in summer and autumn(from June to November)of Zhuqi and Kuiqi sections was analyzed by the partial correlation analysis method. Results show that in recent decades, the water quality of the Minjiang River downstream is generally good and the water quality in the upper reach near the Shuikou reservoir and the lower reach near the estuary changes little. But the water quality of fluvial sections closed to population accumulation area shows a declining trend. Especially in summer and autumn, the DO concentrations in the Zhuqi and Kuiqi sections show an obvious reduction. The DO concentrations in Zhuqi and Kuiqi sections have significantly positive correlations with the runoff of Zhuqi Station, and the partial correlation coefficients are 0. 749 and 0. 866, respectively. The DO concentrations in Zhuqi and Kuiqi sections have significantly negative correlations with the GDP of Fuzhou, and the partial correlation coefficients are -0. 739 and -0. 875, respectively.