摘要
根据在１９９７和１９９８年内对长江干流大通站河水的３次采样分析，结合该站１９６２～１９９０年的水质资料，对长江下游Ｎ、Ｐ含量变化及其输送量进行研究．总氮、总磷的平均含量分别为１．６～２．２ｍ ｇ·Ｌ－ １和０．１１～０．１５ｍ ｇ·Ｌ－ １，Ｎ 以ＮＯ－３ －Ｎ 为主，约占７６％ ，其余主要为溶解有机氮和颗粒氮；Ｐ以颗粒态为主，占９５％ 以上．从５、６月到８月，ＮＯ－３ －Ｎ含量是逐渐降低的，ＤＯＮ含量有较大幅度的上升，ＰＮ、ＰＰ及ＴＰ含量也有所增高．与历史资料相比，长江大通站溶解无机氮（ＤＩＮ）和ＰＯ３－４ －Ｐ含量还在不断上升，Ｎ、Ｐ含量的上升与流域化肥施用量变化趋势一致．１９９８年夏季洪水期间，约有７９．９５万ｔＮ和８．３６万ｔＰ从大通站向下游输送。
Based on the results of sample measurement of nutrient concentrations in the Yangtze River at Datong station in the year 1997 and 1998, combined with historical data of water quality, variations of nitrogen and phosphorus contents and the nutrient loads in the flood of 1998 were discussed. The mean concentration of total nitrogen (TN) were 1 6～2 2mg/L, and NO - 3 N accounted for 76 percent and the other forms mainly were dissolved orgunic nitrogen (DON) and particle nitrogen (PN); mean content of total phosphorus (TP) was about 0 11～0 15mg/L, more than 95 percent of which was in the form of partical phosphorus (PP). The concentration of NO - 3 N decreased from May to August, while those of DON, PN, PP and TP increased in the corresponding time. Compared with the historical data, the levels of dissolved inorganic nitrogen (DIN) and PO 3- 4 P increased partly due to application of chemical fertilizer in the basin. About 799 5 kiloton nitrogen and 83 6 kiloton phosphorus were transported to the low reach during the flood in the 1998. The ratio of DIN and biological active phosphorus far exceeded what the phytoplankton prefers.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2000年第1期53-56,共4页
Environmental Science
基金
中国科学院重大基金
关键词
长江
氮
磷
输送量
水质监测
Yangtze River, nitrogen, phosphorus, concentration, transport.
