半连续培养下东海原甲藻和中肋骨条藻种群生长过程与种间竞争研究

Study on Population Growth Processes and Interspecific Competition of Prorocentrum donghaiense and Skeletonema costatum in Semi-continuous Dilution Experiments

采用半连续培养方法研究了温度和营养盐（N和P）限制对中国东海2种重要赤潮生物东海原甲藻和中肋骨条藻生长及种问竞争的影响。结果表明，东海原甲藻在20℃和25℃时生长状态良好，具有明显的指数增长期，15℃时细胞生长明显受到影响；中肋骨条藻具有较广的温度适应性，15～25℃时均具有明显的指数增长期。东海原甲藻可以忍受低营养盐环境并种群增长，而中肋骨条藻细胞增长需要较丰富的营养盐。在营养盐充足的环境里中肋骨条藻具有竞争优势，相反，在营养盐限制的环境中，东海原甲藻是竞争的优胜者。实验结果与东海原甲藻赤潮爆发现场的环境调查结果基本一致，可以作为解释东海原甲藻赤潮形成原因的依据。

The semi-continuous dilution experiments were used to study the effects of temperature and nutrient limitation on growth and interspecific compitation of Prorocentrum donghaiense and Skeletonema costatum. It is shown from the experimental results that the adaptive temperature range for P. donghaiense is 20 ℃ to 25 ℃ with an obvious exponential growth phase, and the population growth is significantly affected at 15 ℃ ; the adaptive temperature range for S. costatum is 15 ℃ to 25 ℃ with an obvious exponential growth phase. P. donghaiense can live in low nutrient environment with population growth, but S. costatum population growth needs high nutrient environment. S. costatum is more competitive in a rich nutrient environment during an interspecific competition, in contrast, P. donghaiense is the winner in a nutrient-poor environment during an interspecific competition. The experimental results are consistent with the field environmental survey results during the S. costatum red tide events and can be used as basis for explaining the formation cause of S. costatum red tide in the East China Sea.