Responses of Plankton to Filamentous and Toxic Blue-Green Algae

本研究探讨了三个具体的假设， 浮游轮虫和枝角类对 潜在干扰无毒细丝、毒性细胞，以及 蓝绿藻的毒素 这些假设得到了一些人的支持， 现场观察和实验室实验，预测：1） 轮虫，特别是那些有特殊饮食的轮虫， 比枝角类对无毒细丝和有毒细丝敏感， 蓝绿藻的细胞; 2）这种细丝的存在， 有毒细胞会降低枝角类动物 竞争性抑制轮虫; 3）轮虫和枝角类 对外毒素和提取的内毒素同样敏感 蓝绿色藻类。 将通过以下方式检验假设：1） 确定无毒细丝、毒性细胞和 蓝绿藻可溶性毒素对内禀速率 自然增长、摄食率、摄食行为和游泳 各种轮虫和枝角类的行为; 2） 确定轮虫与枝角类竞争的能力 在长期的混合物种培养中， 蓝绿藻的丝状或有毒细胞。 的结果 这些实验将有助于理解和预测 这些藻类对浮游动物种群动态的影响， 自然群落中的物种结构。 干扰蓝绿 藻类，如食动物性鱼类， 枝角类，有利于轮虫的发展。

This study examines three specific hypotheses regarding the responses of planktonic rotifers and cladocerans to potentially interfering non-toxic filaments, toxic cells, and toxins of blue-green algae. The hypotheses, supported by some field observations and laboratory experiments, predict that: 1) rotifers, especially those with specialized diets, will beless susceptible than cladocerqans to non-toxic filaments and toxic cells of blue-green algae; 2) the presence of such filaments and toxic cells will reduce the ability of cladocerans to competitively suppress rotifers; and 3) rotifers and cladocerans will be equally susceptible to exotoxins and extracted endotoxins of blue-green algae. The hypotheses will be tested by: 1) determining the effects of non-toxic filaments, toxic cells, and soluble toxins of blue-green algae on the intrinsic rates of natural increase, feeding rates, feeding behaviors, and swimming behaviors of a variety of rotifers and cladocerans; and 2) determining the abilities of rotifers to compete with cladocerans in long-term, mixed-species cultures with and without non-toxic filaments or toxic cells of blue-green algae. The results of these experiments will be useful in understanding and predicting the effects of these algae on zooplankton population dynamics and species structure in natural communities. Interfering blue-green algae, like zooplanktivorous fish, may slelectively inhibit cladocerans and there by favor the development of rotifers.