| Planktonic algae in lakes and reservoirs is the most important primary productivity, Planktonic algae is closely related to eutrophication, Changes in phytoplankton directly affect the evolution of water quality, it plays an important role in aquatic ecosystems. Phosphorus is the first limiting nutrient density to the algae populations, and therefore control the eutrophication, may depend on the phosphorus control measures. Based on determination the characteristics of planktonic algae phosphorus and alkaline phosphatase activity (APA) and water chemistry factors in water on xilicheng reservoir in Changchun City, combined with simulation experiments, discussed the relations of the characteristics of planktonic algae phosphoru and APA. The results show that:①The water quality in the 7,8,9 month far exceeded, poor water quality, but in 5,6,10 month general meeting inⅢwater standards, water quality was relatively good. TN and TP content of water eutrophication limits, the new legislation was the city reservoir eutrophication; TN and TP more than the eutrophication limits, the xilicheng reservoir was the eutrophication;②Four sampling stations were identified from the phytoplankton 7, 116 species, dominated by cyanobacteria and green algae, followed by Bacillariophyta; August is peak in the number of algae was 6.108×10~7 ind/L;May is the minimum is1.615×10~7 ind/L. The total average number of phytoplankton was 41.1million/L, algae density has exceeded the lower limit of eutrophic water body, belong to eutrophication of water bodies;③APA was significantly correlated to the water of DIP, TP, chlorophyll a, phytoplankton populations, phytoplankton biomass (p <0.05); when the DIP concentration was low enough to maintain water When algae growth, algae, bacteria were induced to produce excess APA and released into the water, APA increased significantly accelerate the decomposition of organic phosphorus in water, DIP concentration; DIP concentration increased with the water, APA was inhibited, water slow down the decomposition of phosphorus, together with algae, bacteria use, water DIP concentrations decreased gradually and, eventually, makes the APA increased gradually;④Xinlicheng Reservoir Microcystis populations present in winter and spring recovery sinking the law; Microcystis groups in the environmental temperature reaches 15℃until recovery, at 20℃under illumination, the maximum growth rate of algae. Light can limit the recovery of Microcystis groups; recovery from the sediment provenance, sediment is the Microcystis population wintering sites;⑤Simulation, the external source of phosphorus (P) the same concentration, TAPA concentration trends in 10℃<15℃<20℃, shows the higher the temperature, APA activity is stronger, the more sediment release of phosphorus, algae recover faster The more biomass; temperature under the same conditions, 10℃for the time TAPA trend P = 0.08 |
PDF Full Text Request