中文摘要：

湖水因季节性分层而导致底层滞水带缺氧的亚深水型湖泊,其沉积物内源磷释放对水体磷循环和富营养化有着重要影响。选取典型的高原亚深水型湖泊——贵州红枫湖为研究对象,借助氧化锆薄膜扩散梯度技术获取了5个代表性湖区沉积物有效磷（labile P）的原位、二维、高分辨分布信息,在此基础上估算夏季红枫湖沉积物内源磷释放通量。结果表明,红枫湖后五沉积物有效磷浓度最高,羊昌河、大坝次之,南湖中与北湖中较低。红枫湖沉积物labile P浓度在亚毫米水平上有很大差异,空间分布不均一,时间上夏季磷释放量为6270-7999kg,占全湖水体总磷的22%-28%。沉积物磷释放是红枫湖水体磷的重要来源,在湖泊富营养化防治过程中应予以重视。

英文摘要：

Phosphorus（ P） released from sediments has a great effect on the lake eutrophication,especially in the deep-water lakes. In this study,in situ two-dimensional,high-resolution distribution of labile P in sediments from five typical lake areas in the Hongfeng lake,a typical sub-deep lake,were characterized using the Zr-oxide diffusive gradients in thin films（ DGT） technique,and the P flux in a summer time was accurately estimated. Our results showed that the labile P concentration in Houwu was the highest among five areas of the lake. Concentrations of labile P in sediments of Yangchang and Dam areas were slightly lower than that of Houwu,and the Mid-north and Mid-south areas have the lowest labile P concentrations. The distribution of labile P exhibited large heterogeneity at the sub-millimeter spatial resolution. The calculated P flux based on the diffusion model ranged from 6270 kg to 7999 kg,accounting for 22% to 28% of the total P of the water.Thus,the internal P is an important source for water P in the Hongfeng lake and should be taken seriously in the management of eutrophication.