营养盐浓度和初始细胞密度对东海原甲藻与塔玛亚历山大藻种间竞争的影响

以我国东海2种重要赤潮原因种--东海原甲藻(Prorocentrum donghaiense)和塔玛亚历山大藻(Alexandrium tamarense)为研究对象,研究了高、低磷酸盐浓度以及初始细胞密度对这2物种种群增长与种间竞争的影响.结果表明,不同实验条件下2物种有不同的竞争结果,营养盐限制环境中主要表现为资源利用性竞争,东海原甲藻为竞争优势种;丰富营养盐环境中,种间竞争具有明显的密度依赖性,根据初始细胞密度的不同,2竞争物种既可以相互排斥,也可能共存.该结果与东海赤潮特征即2物种既可以分别形成单相型赤潮,又可以共同形成双相型赤潮相一致.

Effects of Nutrient Concentration and Initial Cell Density on Interspecific Competition Between Prorocentrum donghaiense and Alexandrium tamarense

In tihs paper, the effects of phosphate concentration and initial cell density on population growth and interspecific competition between Prorocentrum donghaiense and Alexandrium tamarense are studied. It is shown from the study results that the interspecific competition between the two species under low phosphate concentration conditions was characterized by resource-exploiting competition, and P. donghaiense was always the winner~ however, the interspecific competition between the two species under high phosphate concentration conditions was dependent on the initial cell density, and the two species might competitively exclude each other or coexist according to different initial cell densities. The experimental results are consisitent with the observed red tide characteristics in the East China Sea that the two species can generate one dominant species red tide or two dominant species red tide in the East China Sea.