Pisman T I, Somova L A
Institute of Biophysics SB RAS, Krasnoyarsk, Russia.
Adv Space Res. 2003;31(7):1757-61. doi: 10.1016/s0273-1177(03)00117-0.
This study addresses competition between the Paramecium bursaria and zoochlorella-endosymbiosis and the infusoria Paramecium caudatum in a closed aquatic system. The system is a natural model of a simple biotic cycle. P. bursaria consumes glucose and oxygen released by its zoochlorella and releases nitrogenous compounds and carbon dioxide necessary for algal photosynthesis. P. caudatum was fed on bacteria. It was shown that the infusoria P. bursaria united in one cycle with Chlorella had a higher competitive ability than P. caudatum. With any initial percentage of the infusoria in the mixed culture, the end portion of P. bursaria reached 90-99%, which was significantly higher than the end potion of the P. caudatum population. It is assumed that the sustenance expenditures of P. caudatum were greater than those of the endosymbiotic paramecium, i.e. the closing of the components into a biotic cycle leads to a decrease in sustenance expenditures.
本研究探讨了在封闭水生系统中，绿草履虫与其内共生绿藻以及尾草履虫之间的竞争关系。该系统是一个简单生物循环的自然模型。绿草履虫消耗其绿藻释放的葡萄糖和氧气，并释放藻类光合作用所需的含氮化合物和二氧化碳。尾草履虫以细菌为食。结果表明，与小球藻共生在一个循环中的绿草履虫比尾草履虫具有更高的竞争能力。在混合培养中，无论初始草履虫的百分比如何，绿草履虫的最终比例达到90% - 99%，显著高于尾草履虫种群的最终比例。据推测，尾草履虫的维持消耗大于内共生草履虫，即各组成部分形成生物循环会导致维持消耗减少。
