关键词: 铜绿微囊藻, 磷酸盐, 水生态系统, 温度, 迁移, 同位素示踪

Abstract: Effect of temperature on the translocation of exogenous phosphorus in the simulative ecosystem composing of water,Microcystis aeruginosa and sediments was studied with the method of phosphorus isotope tracer. Exogenous ³²P was initially distributed rapidly in the ecosystems in a mode of physical chemistry, irrespective of the influence of different temperature. Then, the translocation of ³²P was significantly affected by the growth of M.aeruginosa in the ecosystem. Relatively high temperature was favorable to the growth of M.aeruginosa and accelerated the adsorption of exogenous phosphorus. The maximum concentration of exogenous endocellular phosphorus in M.aeruginosa was only related with the initial phosphorus concentration of water environment. The growth curve of M.aeruginosa contained short lag phase, 7-day log phase and decline phase but no obvious stationary phase at 25℃. After certain amounts of exogenous phosphorus were accumulated in M.aeruginosa,its growth was independent of the amounts of endocellular phosphorus at 25℃. The exogenous ³²P moved from water and M.aeruginosa to sediment continuously and almost all of them transferred into sediment through the sedimentation of M.aeruginosa at the end of the experiment. The concentration of dissoluble exogenous ³²P declined rapidly when water temperature was high and was less than 0.00716 mg·L^-1 after 7 days.

Key words: Microcystis aeruginosa, Phosphate, Aqueous ecosystem, Temperature, Translocation, Isotope tracer