藻源性颗粒有机物对磷饥饿微囊藻磷富集与生长的影响

以藻源性颗粒有机物为切入点，分别以正磷酸盐（K₂HPO₄）、多聚磷酸盐（Na₅P₃O₁₀）、磷酸单酯（G-6-P）、磷酸二酯（卵磷脂）为参考，对比研究了不同形态的磷对磷饥饿微囊藻生长及对磷富集的影响.研究发现密度为（1.9±0.1）×10⁶cells/mL磷饥饿处理的微囊藻对不能直接利用的Na₅P₃O₁₀、卵磷脂的短期富集作用分别为2.034mg/L、1.030mg/L要明显高于K₂HPO₄的0.491mg/L、G-6-P的0.034mg/L和藻源性颗粒物的0.573mg/L，可能与这些磷素不能迅速进入细胞内，因而被大量的积聚在细胞膜与细胞壁之间有关.微囊藻通过释放碱性磷酸酶等酶系可以大量快速的利用藻源性颗粒物，藻源性颗粒物组中微囊藻生长率0.148d^-1稍低于K₂HPO₄组的0.156d^-1，但均高于其他实验组.实验结束时微囊藻对藻源性颗粒物的利用率57.8%高于K₂HPO₄组的32.5%和卵磷脂组的24.4%.通过液相核磁分析，藻源性颗粒物中磷的组分主要为正磷酸盐、磷酸单酯，并通过计算验证了其对磷饥饿铜绿微囊藻的磷富集与生长的影响.综上，藻源性颗粒物有着极强的生物可利用性，对蓝藻的爆发和持续性有着重要影响.

Effects of the phytoplankton-derived particulate organic matter on the growth and phosphorus enrichment of phosphorus-deficiency Microcystis aeruginosa

The phytoplankton-derived particulate organic matter (POM) in Lake Taihu was taken as the breakthrough point in this study which referenced phosphorus in the orthophosphate (K₂HPO₄), polyphosphate (Na₅P₃O₁₀), orthophosphate monoester (G-6-P) and the orthophosphate diester (lecithin). The effects of phosphorus in different forms on the growth and phosphorus enrichment of phosphorus-deficiency M. aeruginosa was studied. Results showed that the phosphorus-deficiency M. aeruginosa with density of (1.9±0.1)×10⁶cells/mL cannot directly use Na₅P₃O₁₀ and lecithin whose short-term enrichment were 2.034mg/L, 1.030mg/L. It was significantly higher than the 0.491mg/L of K₂HPO₄, the 0.034mg/L of G-6-P and the 0.573mg/L of phytoplankton-derived particulate organic matter (POM). Maybe these forms of P cannot enter the cells and were accumulated between the cell membrane and cell wall. M. aeruginosa can use the phytoplankton-derived POM rapidly by releasing alkaline phosphatase enzymes. The growth rate of M. aeruginosa with phytoplankton-derived POM was 0.148d^-1 and was slightly lower than the 0.156d^-1of K₂HPO₄, but it was much higher than the rate of other groups. The utilization rate of phytoplankton-derived POM in the end of the experiment was 57.8% which was higher than the 32.5% of K₂HPO₄ and the 24.4% of lecithin. The composition of phosphorus in phytoplankton-derived POM were mainly orthophosphate and monoester by using liquid-phase NMR analysis. And we verified the effects of it on the growth and phosphorus enrichment of phosphorus-deficiency M. aeruginosa by calculation. In conclusion, the phytoplankton-derived POM had a strong bioavailability, and was very important to the outbreak and persistence on algae bloom.