利用^137Cs定年技术对骆马湖沉积物柱状样进行了定年,同时测定了沉积物中重金属和营养盐含量的垂直剖面与水平分布。结果显示:骆马湖沉积物的平均沉积速率为3.5 mm/a;在垂向上,随着沉积物深度变浅,营养盐含量逐渐升高,而大部分金属元素含量保持稳定或减少,只有Cd和Pb含量明显升高;在平面上,大部分金属元素的含量峰值出现在湖心区域,而营养盐的含量峰值出现在西部和南部湖区。可见骆马湖受人为污染影响严重的主要是重金属中的Cd与Pb和营养盐,且湖心区域污染较重。
The ^137Cs isotope dating method was used to determine the dating of sediment cores in the Luoma Lake, and the vertical profile and horizontal distribution of heavy metals and nutrients were investigated. The results showed that (1) the average sedimentation rate of Luoma Lake is 3.5 mm/a; (2) the nutrient contents increase gradually and the contents of most heavy metals decrease or stay stable with the decreasing in depth, while the contents of Cd and Pb increase; and (3) the peak values of most heavy metals occurin the center of the lake, whereas the peak values of nutrients occur in the west and south of the lake. Therefore, the main pollution in the Luoma Lake was caused by Cd, Pb, and nutrients, and it occurred mainly in the center of the lake.