Loading Of Nutrient Salts And Plankton Research In The Three Gorges Reservoir In Chongqing City

The Three Gorges Project (TGP) on the Changjiang River is the word-famous largest hydrodynamic project. It will possess comprehensive utilization benefits for flood control, power generation and navigation improvement. But the construction of TGP will produce widespread and profound impact on ecology and environment.Aquatic eutrophication is a prevalent ecological problem. The nutrient salts level of the major portion of the lakes and reservoirs in china reachs the concentration of eutrophication fundamentally. Eutrophication of water body is very serious in many lakes and reservoirs. In recent years, Plankton bloom has happen successively in many branches of Changjiang river such as Wujiang river, Hanjiang river and Da-ning river. The trend of eutrophication of water body gets more and more noticeably. More and more person paid attention to Whether the Three Gorges will meet the same problems.With the Three Gorges Reservoir starting water storing, the hydraulic condition of Changjiang river change a lot and became a typical channel reservoir. Flow velocity of water in this area sharply decreased much than before, and water flow velocity would decrease from 2 m/s to 0.25～0.5 m/s. It would seriously impair its transport and diffusion for contaminants. Deposition of suspended solid make the water body clearly and diaphaneity highly. All these changes will make for photosynthesis of aquatic plant, especially algae. It increases the possibility of eutrophication in the Three Gorges Reservoir.The main research contents and result of this thesis are as follows:1,Explain the theory of eutrophication of waterOn the base of referring to broad data of domestic and overseas, the paper expatiate the theory of eutrophication of water. It also introduced the harm, character of eutrophication of water.2,Analysis the sources and loads of nutrient saltsIt is review and analysis the water quality monitoring historical data of Three Gorges reservoir.Through the deeply study on the income sources and loads of nutrient N and P, it is found that the load of N and P in water body of Changjiang river is in a high assay level. The nutrient salts are mainly come from upstream and non-point source.