黄海两种典型硅藻的磷胁迫生理研究

Physiological responses of two typical species of diatoms to phosphorus stress in Yellow Sea

在实验室批次培养条件下,研究黄海两种浮游植物优势种玛氏骨条藻(Skeletonema marinoi)和旋链角毛藻(Chaetoceros curvisetus)在低磷条件下的生长特性、环境中不同形态磷浓度的变化以及磷饥饿状态下浮游植物的营养吸收动力学和碱性磷酸酶动力学。结果表明,玛氏骨条藻在磷胁迫情况下可利用自身较高的吸收速率和较小的细胞体积有效摄取环境中的无机磷快速生长并取得优势,而旋链角毛藻在无机磷的利用上并无优势,其比玛氏骨条藻需要更多的细胞颗粒磷去维持细胞活性,而且更容易诱导碱性磷酸酶分解利用有机磷,推测在有机磷丰富的环境下旋链角毛藻会在二者竞争中取得优势。这些生理特性有可能是二者在黄海季节性水华发生过程中大量存在的原因。

Using batch culture experiments, this study was focused on the physiological responses of Chaetoceros curvisetus and Skeletonema marinoi, two typical diatoms in the Yellow Sea, to phosphorus stress. The results showed that both of the test species could utilize the different phosphorus pools from ambient and cells to dissimilar extent under phosphorus stress. S. marinoi preferred utilizing soluble reactive phosphorus（SRP） from ambient while C. curvisetus liked to utilize particulate phosphorus in cells. Due to different abilities and strategies of utilizing SRP and soluble nonreactive phosphorus（SNP）, S. marinoi might be a more advantaged competitor in SRP condition while C. curvisetus might be results might be helpful to explaining the reason why the bloom in the Yellow Sea. a more advantaged competitor in SNP condition. These two species can out-compete others in frequent diatom bloom in the Yellow Sea.