围隔生态系内浮游植物对富磷的响应

摘要

在长江口外应用围隔生态系实验方法，研究了富磷与浮游植物生物量的相关性以及浮游植物对磷吸收的种间竞争。结果表明，可溶性磷(主要是PO-34)在实验的第5天以前呈指数函数减少，浮游植物生物量则反之。当浮游植物细胞数量和叶绿素a达到最高峰时，种类多样性指数和均匀性指数处于最小值，分别为0.008和0.003。这次实验引发了中肋骨条藻(Skeletonema costatum)赤潮。文中还探讨了中肋骨条藻的分裂速度以及对磷的吸收速度。%The correlation between the excess phosphate and biomass of phytoplankton and species composition was studied by mesocosm experiments in the water of Changjiang River Estuary.After adding the phosphate,the biomass of phytoplankton increased exponentially and the concentration of dissolved inorganic phosphate decreased exponentially until the fifth day.When the density of phytoplankton and the concentration of chlorophyll a reached the peak,the species diversity and evenness declined to the lowest.These two indexes were 0.008 and 0.003 respectively.The red tide of Skeletonema costatum was induced by adding phosphate.The growth rate of Skeletonema costatum and uptake rate on phosphate were estimated.