Study On Phosphorus Uptake And Storage Mechanism Of Four Kinds Of Cyanobacteria

Microcystis aeruginosa, aphanizomenon flos-aquae, anabaenaflos aguae and group millirod algal are several typical advantages in Dianchi lake algae blooms. The excess nutrient input caused outbreaks of algal blooms frequently. Phosphorus has been considered to be the first limiting nutrient for phytoplankton growth. Therefore, the further studies on the physiological and biochemical response of different phosphorus sources towards different cyanobacterial blooms, is helpful to further understand the mechanism of cyanobacteria phosphorus metabolism and the competition relationship. This paper focus on four kinds of cyanobacteria of phosphate, organic phosphate, absorption and utilization of phosphorus compound and four species of cyanobacteria in three different forms of phosphorus absorption and storage dynamics. It aims to reveal different cyanobacteria utilization ability of organic and inorganic phosporus. The main research results are as follows:(1).By measuring orthphosphate concentration and total phosphorus concentration of Microcystis aeruginosa in different training period. We founded orthophosphate concentration are accounted for a large share of total phosphorus concentration, which showing that Microcystis aeruginosa can absorption a mass of orthophosphate within a certain range of phosphorus concentration, and the existence of a main form of phosphorus in orthophosphate in the body. By comparisoning of the orthophosphate concentration in two kinds of different forms of Microcystis algae, indicating that orthophosphate absorption of Microcystis is stored in algae layer outside the cell membrane.(2).By the analysis of the four kinds of cyanobacteria of polyphosphate absorption and utilization, the results show that sodium pyrophosphate can quickly be degraded for orthophosphate in four kinds of extracellular algae. At the same time, the degradation rate is far greater than the natural degradation rate. After a period of incubation, the concentration of extracellular phosphate concentration is basically equal to the total phosphorus. That is the first extracellular phosphate decomposed into orthophosphate again by four kinds of absorption and utilization of cyanobacteria.(3).Comparison four kinds of cyanobacteria extracellular phosphate concentration under the developing of sodium glycerophosphate, it found out that the Microcystis aeruginosa and a.flos-aquae extracellular phosphate concentration increased rapidly, and reached the maximum value in 8 days, which is equal to the total phosphorus concentration. When you compare the algal extracellular orthophosphate orthophosphate concentration changes and degradation under natural light, you will find 8 days before the training, the existence of algal cells have greatly contributed to the degradation of beta glycerophosphate because Macrocytic aeruginosa and Aphanizomenon Flops aquae to degrade in the extracellular algae cells at first. And then it is absorbed by the phosphate. Anabaena Flos aquae and Microcystis group extracellular orthophosphate concentrations increase little in the amount, and in the early stage of culture, its value is less than the concentration of phosphorus measured under natural light degradation. But the total phosphorus concentration has decreased with the increase of culture time, ultimately remained unchanged. Therefore, Anabaena Flos-aquae and Microcystis populations of glycerophosphate uptake in two ways:One part is directly absorbed and utilized, the other part is first degraded and absorbed, but mainly is direct absorption and utilization.(4).Composite P treatments in different proportions, Macrocytic aeruginosa and a.flos-aquae extracellular TP concentration are in the fall. At the same time it has a certain degree of increase in phosphate concentration, and total phosphorus concentration are equal. It shows that Microcystis aeruginosa and a.flos-aquae in absorption and utilization of organic phosphorus degrading phosphate and extracellular algal cells can directly absorb phosphorus utilization. Anabaena Flos aquae and Microcystis cell groups outside the concentration of total phosphorus and phosphate concentrations are decreased synchronously, and the total phosphorus concentration decrease much more than decrease orthophosphate concentration. It also tells us Anabaena Flos aquae and Microcystis populations are in the absorption and utilization of phosphate and in the direct absorption of extracellular organic phosphorus. The growth curve of four kinds of composite phosphorus source of cyanobacteria in different proportions under pure organic phosphorus in experimental group showed that the algal biomass minimum, pure inorganic phosphorus in experimental group, will promote the composite phosphorus source with different proportions for the four kinds of algae growth. It showed that under the compound phosphorus source and the proper ratio, the algae growth can promote and reproduce more than a single phosphorus source, which is conducive to the formation of bioom. (5)Four kinds of cyanobacteria respectively storage absoipiion kinetic parameters Km and Vmax indicates that the maximum absorption rate in three different forms of phosphorus source. Microcystis aeruginosa, a.flos-aquae and Anabaena. Microcystis are the strongest affinity for orthophosphate and the group of glycerophosphate sodium phosphate AF minimum Km value, the highest value of Km. but the maximum absorption rate of orthophosphate Vmax. The maximum absorption rate of sodium phosphate is the minimum focus. It showed that group affinity of Microcystis on phosphate and organic phosphorus was higher than phosphorus phosphate, and in a certain range of concentration of phosphorus, phosphorus concentration increased with the extracellular. The absorption and storage capacity of four kinds of cyanobacteria in three different forms of phosphorus are increasing. Several cyanobacteria in three different forms of phosphorus source lower than the growth rate of experimental show that four kinds of cyanobacteria in orthophosphate is lower than the growth rate. The best growth status of organic phosphorus was in the experimental group.The specific minimum growth rate of Microcystis aeruginosa under low phosphorus concentration was the best. The other three kinds of algae growth rate with extracellular phosphate concentration increased slightly. But there is no significant difference in phosphorus, abundant, algae is preferentially absorbed by phosphate, phosphorus in four kinds of defects period, cyanobacteria cyanobacteria could be absorbed by other forms of phosphorus (phosphate and organic phosphorus), for the normal growth and reproduction of algae, and extracellular phosphorus concentration of different the algal growth was not affected.