不同氮磷比对米氏凯伦藻和中肋骨条藻种群竞争的影响

Inter-specific competition of Kareniamikimotoi and Skeletonemacostatum Under Different Nitrogen and Phosphorus Ratio

采用单养和混养方法研究不同氮磷比培养条件下（1∶1、10∶1、25∶1、50∶1、75∶1、100∶1、150∶1）对米氏凯伦藻（Karenia mikimotoi）和中肋骨条藻（Skeletonema costatum）生长和种间竞争参数的影响。结果表明：单养时,米氏凯伦藻和中肋骨条藻的最适氮磷比都为50∶1（N：150μmol/L、P：3μmol/L）,米氏凯伦藻和中肋骨条藻分别在氮磷比值为25～75、25～150之间能保持较好的生长。混合培养条件下,两种微藻的环境负载能力（K）、生长率（r）都低于单独培养。中肋骨条藻在各个氮磷比条件下的竞争中完全处于优势,中肋骨条藻对米氏凯伦藻的抑制参数β均高于米氏凯伦藻对中肋骨条藻的抑制参数α,并且β：α随着氮磷比的升高而升高。

The experiment were carried out in mono-culture and co-culture,the growth character and competitive inhibition parameters of Kareniami kimotoi and Skeletonema costatum were studied in culture of different ambient ratios of N and P（1：1、10：1、25：1、50：1、75：1、100：1、150：1）.The results showed that the twoalgaes most suitable ambient ratios of N and P were both50：1（N：150μmol/L、P：3μmol/L）,when under mono-culture,and Karenia mikimotoi could growth better when ambient ratios of N and P is 25-75 while Skeletonema costatum is 25-150.The environmental capacity（K）and intrinsic rate of increase（r）of co-culture is much lower than mono-culture.Skeletonema costatum is dominant under all ambient ratios of N and P.The competitive inhibition parameters of Kareniami kimotoi to Skeletonema costatum（β）was higher than that of Skeletonema costatumto Kareniami kimotoi（α）,and value ofβ∶αbecame higher with the ambient ratios of N and P.