Seasonal Succession Of Algae Functional Groups And The Physiological Changes In Different Water Dynamic Conditions

Eutrophication of lakes and reservoirs is one of the important issues in the field of environment, water quality problem caused by eutrophication, especially in water of the algae growth in varying degrees of impact on the production and life of people. Taking Xi’an five main body waters as a case study, the research combined the methods of on-line water quality monitoring and Periodic experiment analysis of algae. Focusing on the following three points:1. The relationship between functional groups and environmental factors of five main water bodies in Xi’an City. 2. Effects of hydrodynamic conditions on the growth of functional groups in deep water reservoir. 3. The physiological changes of Chlorella under the water dynamic conditions.(1) The detection of 10 functional groups: B, P, D, X1, M, MP, F, S1,, J, G, B, P, D, X1 for several common advantages of the lake library group. Feature group B were higher in the spring and summer, functional group P were higher in the spring and summer, functional groups D biomass more in spring and autumn, functional group X1 in the summer and fall season biomass more.(2) In different regions of the water body, the position of the latitude is larger, even if the nutritional status is similar, the functional groups of algae is very different. In different regions of the water body, the latitude position is similar, even if the nutritional status is different, the algae functional groups are similar, but there are differences in biomass, especially the Dominant Algae function group.(3) In the study of deep reservoir, through the correlation redundancy analysis shows that, the main function of group B, P, MP and j and reservoir water dynamic conditions(water level and access flow) is negative correlation, reservoir water level and access to flow to the growth of the algae functional group has significant influence. In the stage of reservoir water level rise and high water level stabilization, the B and P biomass were less in the functional group, and the B and P biomass were more in the functional group during the stage of lower water level and the stable stage.(4) Through the research on the growth inhibition of Chlorella disturbance conditions found that disturbance can effectively inhibit the growth of Chlorella cells. Chlorella in disturbance late chlorophyll a and carotenoid pigment concentration is almost zero, indicating that the inclusions composed of organelles has been irreversible damage, inhibit the normal physiological metabolism of algae cells. Before and after the disturbance, Chlorella cells within the enzyme activity occurred some changes, in Chlorella vulgaris MDA in different disturbance intensity declined. And compared with the SOD enzyme, the fluctuation of MDA is larger, but the gradient change is more consistent.(5) after the disturbance of Chlorella by SEM and TEM analysis found, Chlorella cells occur deformation, by the original circular or oval become irregular in shape. Cell surface structure changes, the internal physiological function of the cell was destroyed, the cell lost the ability to synthesize energy, resulting in cell death.