The Effects Of Velocity Of Glow To The Growth Of Algae In Low Current Area Of The Three Gorges

After Three Gorges Reservoir storing up to 175m, the water level of the front and backwater of tributaries will be raised, and the velocity of flow will be lower. This will make for bed load sediment, reduced the nephelometer and increased the transparence, which will be propitious to the growth of algae and lead to water boom. These regions become sensitive for investigative entrophication. According to the related research, from the first step analysis to main variety water environment trend in Three Gorges Reservoir, the higher total density of TP and TN is one but may not the main reason of entrophication. The conditional hydrodynamic changes may be the primarily factor to enrich entrophication in this regions. But under current nourishment salt is been difficult to control, enrich the water motive term especially critical current velocity is the measurement conduct and actions occurrence the entrophication turns to induct primarily the factor takes into the research and then become increasingly important.This thesis proceeded the indoors and outdoors to experiment with aglae growth in respectively in assumption foundation that put forward the critical current velocity, and making sure the relation of current velocity and algae growth, and find out the critical current velocity of some algae. In a specific way as follows:From the indoors experiment, we can discover that water boom may be take place in flow of water, and the critical current velocity uncertain for zero; Find out the growth of Chlorella ellipsoidea's best hydrodynamic environment; Put forward Jailing river has the possibility of the occurrence water boom at current nourishment appearance, of so have not taken place, because in addition to temperature lowery, water current velocity than may repress the algae growth quickly.Passing the outdoors experiment discovers, the current velocity influence that grow has four functions primarily to algae, distinguishing for the defer, accelerates, repress and promote;When current velocity is 0.001 m/s, 0.1 m/s, 0.5 m/s, the water flow repressed the algae growth, current velocity is 0.005 m/s, 0.01 m/s, 0.05 m/s, water flow promoted the algae growth; According to current velocity to influence coefficient that algae grow, get an aggrandizement for different current velocity descending total growth in Chla trend, with current velocity, the growth of algae increases immediately, arriving a max value, then reducing gradually, getting critical current velocity that a algae grow is maybe about 0.05 m/s;The critical current velocity that Chlorella rulgauis grow is about 0.05 m/s; The critical current velocity of the Ankistiodesoum is about 0.01 m/s;The influence of Current velocity to the growth of Scenedesmus and Anabaenopsis is less, which need the further experiment; It was to verified esse and the characteristics of the critical current velocity. In addition to current velocity, because algae growth still be influenced by water temperature, light shining on, nourishment salt etc. factor. For this reason, on the foundation of analyze every kind of interference factor in this thesis, then put forward the experience improvement direction, for further investigate the current velocity to the growth of algae.