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The research papers in the Three Gorges Reservoir in Xiangxi Bay blooms as a starting point, combining the basic theory of the environment, ecology, fluid mechanics, and the use of field monitoring, control experiments, numerical simulation and other technical means, systematic analysis of the Three Gorges Reservoir Xiangxi the law of the river water bloom algae bays vertical migration characteristics, optical characteristics, water temperature characteristics, nutrient characteristics, water power and district characteristics, the the the algae vertical migration model and the bloom algae vertical distribution model, Xiangxi Bay the algae bloom Mechanism and the Three Gorges Reservoir Emergency control measures. The specific results are as follows: 1. Analysis Peridiniopsis (Peridiniopsis sp.) Diurnal vertical migration characteristics, compare the proposed dinoflagellate bloom and the diatom bloom chlorophyll a concentration difference between day and night. The results showed that the water column above the water depth of 12 m Peridiniopsis exist cyclical diurnal vertical migration characteristics, diatoms diurnal vertical migration characteristics are not significant; the algal blooms existing, scattered in the waters of algae groups under suitable conditions floating gathered together; the affect intended to dinoflagellate diurnal vertical migration factor is underwater lighting and water temperature vertical distribution, its cycle of rhythmic movement intended dinoflagellate vertical migration also have some impact. Analysis Xiangxi Bay surface illumination variation, Xiangxi Bay underwater light attenuation characteristics and its influencing factors, and a trial of Xiangxi Bay euphotic Temporal and spatial characteristics of water China's impact. The results show that the light of the Xiangxi River water changes with the seasons, spring and autumn light moderate, suitable for the growth of algae; winter light minimum light summer, more than 100000 lux;; the Xiangxi Bay Underwater extinction coefficient with turbidity, chlorophyll a concentration showed a significant positive correlation between most of the time, the phytoplankton biomass is the main factor to affect the extinction coefficient of the Xiangxi Bay underwater, underwater extinction coefficient of transparency was a significant positive correlation between the reciprocal; Xiangxi Bay the thickness of the euphotic winter, spring and smaller the summer changes significantly, the upstream water euphotic mainly affected by the impact of the phytoplankton biomass, the downstream water euphotic mainly affected by the effects of the Yangtze River with sand water intrusion. 3. Analysis of the the Xiangxi Bay special water temperature stratification status quo, and combined with the hydrodynamic characteristics of the special water temperature stratification of the causes of its relations with the bloom in Xiangxi Bay. The results show that the Three Gorges reservoir dry water body as a whole in a mixed state, only weak stratification in March, the annual maximum water temperature difference between the bottom of the table does not exceed 2 ° C; the Xiangxi Bay water temperature vertical distribution of space-time the difference is significant, downstream near the mouth of the Bay The waters of the Yangtze River water intrusion, water vertical stratification is not obvious; Bay of upstream water by upstream cryogenic bottom density current impact, water vertical stratification higher degree; end of the Bay, the Three Gorges reservoir season scheduling, water vertical The stratification was seasonal changes. Established Xiangxi Bay Water, underwater lighting model, put forward the concept and nature of biological force (biotic force) and this basis algae migration momentum equation, the the algae vertical migration model and to verify, thereby establishing water bloom algae vertical distribution of one-dimensional model and discussed. The results showed that the biological force individual organisms to adapt to the surrounding environment and adjust their own physiological conditions exist certain to change their state of motion adjustment force, limiting its appropriate qualitative and uncertainty to meet GuassAmp curve; affect algae The major factor in the water distribution is algae migration characteristics, the the algae growth characteristics and water mixed layer thickness, the more obvious the algae own migration characteristics, the greater the thickness of the euphotic water mixed layer thickness is smaller, more easy to form water bloom, and vice versa is not easy to form water blooms, the water of the Bay of drier water body prone to this natural phenomenon in the bloom theoretically reasonable explanation; different algae species in the vertical distribution characteristics of the water bodies of the same main reason is the different algae species in water movement in different condition. With the the Xiangxi Bay hydrodynamic characteristics of the Three Gorges Reservoir, analysis of the Xiangxi Bay-based density current dynamic context nutrient characteristics proposed the Xiangxi Bay hydrodynamic, water environment partition law. The results show that the Three Gorges Reservoir in Xiangxi Bay layered significantly different flow characteristics, the Yangtze River water perennial water exchange in the form of the intrusion temperature differences heavy flow and Xiangxi Bay, the Xiangxi Bay upstream low temperature to flow to the bottom slope different a heavy flow sneak into the Bay, and flows into the Yangtze River; Xiangxi River Basin water exchange area (exchange zone) can be divided into the transition zone (transition zone), the retention area (stagnant zone), changes in area (fluctuation zone), rivers (stream zone), five different ecological area of ??the environment, water temperature stratification of stagnant zone significantly less water body up and down blending nitrogen nutrition comes mainly from the main stream of supplies, phosphorus, silicon, and other nutritional comes mainly from upstream to stream and urban sewage, water bloom The sensitive index greater than 0.5, the most vulnerable to an outbreak of high-intensity water bloom. Analysis the emergency regulation mechanism of the the algae bloom mechanism, Xiangxi Bay of Three Gorges Reservoir and its Three Gorges Reservoir, and proposed the corresponding emergency regulation program. The study shows that the intrusion density flow occurs in the table, the middle period, the water level of the Three Gorges Reservoir day uplift 1.0-1.5 m, that make Tributaries Bay in the formation of the upper body of water flowing into the Bay of lower body of water out of the Bay, the water cycle process; water exchange process Tributaries Bay water vertical stratification status change, reducing the reservoir dry tributaries between differences of temperature, pH, turbidity, nutrients and other factors; broke the original Bay of hydrodynamic, nutrient and water bloom partition characteristics, by increasing the exchange of water between the dry tributaries, destruction of the Bay, water column stratification state increased the tributary sediment content mechanisms temporary suppression \up to 2.38 m, the date of dispatch larger space; proposed using spring \fall ahead of emergency control program to control water programs.
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