摘要
根据1998年和1999年秋季在长江干流从重庆至长江口进行的纵向采样和分析,对长江干流的各态氮、磷含量的沿江变化进行研究.从整体上了解长江干流的水质变化特性,特别是营养盐含量的分布状况.研究结果表明,长江干流的ss浓度很高,介于50～400mg/l.TN、TP浓度分别在70～110 μmol/L、2～25 μmol/L之间,前者以NO3-N为主,后者以PTP为主,PO4-P含量仅占TP的10%～20%.DIN/PO4-P的比值在70～160之间,远高于浮游植物生长P限制值,表明长江口及临近海域中P可能是生物生命活动的主要限制因素.葛洲坝水库对ss、TP、TN、NH4-N、BOD、COD等水质有一定的净化作用.长江水体在通过各大城市以及两大湖泊时,BOD、NH4-N负荷的增加迅速,特别是通过重庆、武汉、南京、上海及洞庭湖和鄱阳湖之后尤为明显.N、P含量的上升与人口增长、生活污水排放量及流域内化肥施用量增加有关.洞庭湖和鄱阳湖水系以及周围的面源负荷,对长江流域的营养盐变动有很大的影响.
In order to better understand the biogeochemical process of the Changjiang (Yangtze) River and pollutant load flowed into the East China Sea from the river and provide scientific basis for eco-environmental and water resources protection, field surveys along the Changjiang River from Chongqing to Shanghai (about 2300 km long) were carried out in autumns of 1998 and 1999 through the international cooperative study between the National Institute for Environmental Studies (NIES), Japan and the Changjiang Water Resources Commission, China. In this paper, the preliminary results of water quality conducted in the joint survey were presented. From the concentration variations of SS, DOC, T-P, NH 4 -N, NO 3 -N and DT-N along the main course of the Changjiang River during both surveys of 1998 and 1999, it is evident that the concentrations of SS and nutrients in the autumn of 1999 were higher than that in the summer of 1998, because the influence of non-point pollutant source and the discharge and water level during the survey period in 1999 was much higher than that in 1998. On the other hand, the general tendency of the nutrient distribution increased from upstream to downstream along the main course of the Changjiang; the concentrations of nutrients were evidently higher in the downstream of big cities than that in the upstream of these big cities. Water quality was improved after passing through the Gezhouba Dam. It was also found that the BOD and NH 4 -N concentrations increased sharply after passing Dongting and Poyang lakes.
出处
《地理学报》
EI
CSCD
北大核心
2004年第1期118-124,共7页
Acta Geographica Sinica
基金
日本国环境省"流域环境管理国际共同研究(重点共同研究)"项目~~
关键词
长江
营养盐
氮
磷
污染负荷
Changjiang River
nitrogen
phosphorus
pollutant load
Dongting Lake
Poyang Lake
Gezhouba Dam
