淮河流域焦岗湖水质参数时空变化及影响因素

Spatio-temporal variations and impact parameters of water quality in Lake Jiaogang,Huaihe Basin

焦岗湖是淮河左岸一个天然湖泊,集防洪、灌溉、养殖、旅游等多种功能于一体.利用焦岗湖4个季节水质监测数据,运用Kriging方法,分析焦岗湖水质参数的时空变化及影响因素.结果表明:由于受水文季节变化过程及人类活动等综合影响,焦岗湖水质参数在时间及空间上均存在一定差异.从时间变化来看,夏季透明度较低、秋季较高;溶解氧浓度在春、冬季显著高于夏、秋季;总氮、总磷浓度与高锰酸盐指数均表现为夏季最高、秋季最低.从空间变化来看,4个季节的透明度空间差异较为显著;溶解氧浓度在春、冬季空间分布较为均匀,夏季呈现中心高周围低的变化趋势,秋季则表现为西高东低;总磷浓度春季分布较为均匀,夏、秋及冬季则呈西高东低之势;高锰酸盐指数在春、秋季节呈现东高西低之势,夏季高浓度主要集中在湖区北部,冬季浓度变化不大.

Lake Jiaogang is a natural lake on the left bank of the Huaihe River, which plays an important role in flood control, irri- gation, aquaculture and tourism. In this study, spatio-temporal variation and impact parameters of the water quality were analyzed using the monitoring data of the four seasons of Lake Jiaogang, by using Kriging method. The result indicated that the water quality parameters of Lake Jiaogang showed changes at temporal and spatial scale due to the effects of hydrology and human activities. In views of seasonal changes, the water transparency was lower in summer and was higher in autumn. Dissolved oxygen concentration in spring was significantly higher than that in summer, autumn and winter. The concentrations of total nitrogen, total phosphorus and permanganate index were the highest in summer and the lowest in autumn. The spatial difference of transparency of the four seasons was significant. The spatial distribution of dissolved oxygen was more uniform in spring and winter. The summer dissolved oxygen showed a tendency that the concentration in the central lake was higher than the surroundings. The dissolved oxygen concen- tration in autumn was high in the west and low in the east of the lake. The distribution of total phosphorus was much uniform in spring, and the total phosphorus concentration was high in the west and low in the east in summer, autumn and winter. Index of permanganate concentration showed a tendency that it was high in the east and low in the west in spring and autumn, which a high index was mainly concentrated in the north lake in summer but the index changed little in winter.