乌江流域不同营养水平的梯级水库沉积物中磷形态特征  

Distribution of phosphorus forms in the sediments of cascade reservoirs with different trophic states in Wujiang catchment

作　　者：尹然[1] 汪福顺[1] 梅航远[1] 姚臣谌[1] 郭梅云[2] 

机构地区：[1]上海大学环境与化学工程学院,上海200436 [2]海河流域水环境监测中心,天津300177

出　　处：《生态学杂志》2010年第1期91-97,共7页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(90610037和40873066);上海市启明星计划项目(08QA14029);上海市重点学科(第3期)项目(S30109);环境地球化学国家重点实验室基金资助项目

摘　　要：分析了乌江干流及支流不同营养水平的梯级水库(东风-贫营养、红岩-中营养、乌江渡-富营养)沉积物粒度的垂向分布,并以改进的连续提取法(SEDEX)调查了不同磷形态垂向分布特征。结果表明:3水库沉积物粒径均随深度的增加而减小,东风水库粒径最大,红岩水库其次,处于下游的乌江渡水库粒径最小;乌江渡、红岩和东风水库沉积物总磷(TP)的平均含量分别为2.07、1.22和1.11mg.g-1,总无机磷分别占到总磷53.8%、44.5%和81.9%,有机磷占TP的41.9%、55.5%和18.1%;3水库各形态磷所占比例不同,其中,乌江渡水库交换态磷所占比例相对较大,与其富营养化状态一致;乌江渡水库沉积物表层10cm,各形态磷含量随深度的增加呈下降趋势,红岩水库除交换态磷,其他各形态磷变化趋势不明显。东风水库各形态磷变化趋势不明显;河流梯级开发使下游水库颗粒物粒径变小,从而使下游水体中的磷更易吸附和释放,下游水库沉积物与水体交换也更强烈,除总磷外,交换态磷、自生磷和有机磷也可较好地反映水库富营养程度及演变。This paper analyzed the vertical distribution of sediment grain size in the Dongfeng reservoir （oligotrophic state）, Hongyan reservoir （meso-trophic）, and Wujiangdu reservoir （eutrophic） on the Wujiang River, and by using advanced sequential extraction method （SEDEX）, studied the distribution of different phosphorous （P） forms in the sediments. In the three reservoirs, sediment grain size decreased with increasing sediment depth. Dongfeng reservoir had the largest sediment grain size, followed by Hongyan reservoir, and Wujiangdu reservoir. The total P contents in the sediments of Wujiangdu, Hongyan and Dongfeng reservoirs were 2. 07, 1.22 and 1.11 mg·g^-1, in which, inorganic P occupied 53.8% , 44. 5% and 81.9% , and organic P occupied 41.9%, 55.5% and 18. 1% reservoir, which was consistent with , respectively. The exchangeable P was higher in Wujiangdu the trophic state of the reservoir. In the surface layer （0-10 cm） of the sediments, all P forms in Wujiangdu reservoir decreased with depth, those in Dongfeng reservoir had less change, and only exchangeable P in Hongyan reservoir changed obviously. Due to the cascade exploitation of hydropower, the reservoir in the downstream had smaller grain size, and thus, the sediments in the reservoir had stronger adsorption capability to overlaying water P. It was suggested that sediment total P, organic-P, Ca-bound P, and Fe-bound P could be the useful indicators for the evolution of the trophic levels of reservoirs.

关 键 词：沉积物 分形态磷 粒度 梯级水库 

分 类 号：X524[环境科学与工程—环境工程]