1. Although considered a key functional trait, little is known about how zooplankton feeding mode affects top‐down regulation of phytoplankton communities. Indeed, copepods are expected to promote the dominance of toxic phytoplankton by selective removal of their edible competitors; however, empirical evidence comparing the effect among calanoid and cyclopoid copepods is lacking.
2. We compared the top‐down effects of two copepods with contrasting feeding modes—the calanoid Notodiaptomus iheringi (current feeder) and the cyclopoid Thermocyclops decipiens (ambush feeder) — on the relative and absolute biomass of the filamentous cyanobacterium Raphidiopsis raciborskii co‐cultured with the nutritious eukaryotic phytoplankton Cryptomonas obovata in a week‐long laboratory assay.
3. The current feeder had a stronger top‐down effect on the biomass of both prey throughout the experiment, with mass‐specific clearance rates 3–5× higher than ambush feeder. By the end of the experiment, the current feeder significantly reduced cyanobacteria biomass compared to controls while the ambush feeder did not. During the week‐long experiment, the current feeder switched from grazing on edible prey to cyanobacteria as the former became less abundant.
4. Contrary to expectation, neither of the copepod species promoted cyanobacterial dominance by the end of the experiment. This is because both grazers, but especially the current feeder, initially increased but subsequently decreased the relative contribution of cyanobacteria to total phytoplankton biomass. Moreover, both copepods decreased the length of cyanobacteria filaments by c. 70%
5. Current feeders can switch from edible prey to cyanobacteria when the abundance of shortened filaments surpasses the abundance of edible prey. While top‐down regulation of phytoplankton can be stronger for current feeding copepods, ambush feeding copepods can have a significant role during blooms by shortening cyanobacterial filaments. Hence, the broader role of contrasting copepod feeding traits on phytoplankton communities merits further study.

中文翻译：

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在多个猎物世代中，从猛禽到当前的co足类动物，自上而下的丝状蓝细菌调节都不同

1. 尽管被认为是关键的功能性状，但对浮游动物的摄食方式如何影响浮游植物群落自上而下的调节知之甚少。确实，足类动物有望通过有选择地去除其可食竞争者来促进有毒浮游植物的优势。然而，目前尚缺乏经验证据来比较类颅骨和类环足co足类动物之间的作用。
2. 我们比较了两种co足类动物的自上而下的进食方式（对比喂食器类的类人猿类odi蛇（Notodiaptomus iheringi）和摆线虫类Thermocyclops decipiens（am虫喂食器））对与蓝藻Raphidiopsis raciborskii共培养的丝状蓝藻相对和绝对生物量的影响。在长达一周的实验室检测中，营养丰富的真核浮游植物隐孢子虫。
3. 在整个实验过程中，当前的喂食器对两个猎物的生物量都有更强的自顶向下作用，其质量特异性清除率比伏击喂食器高3–5倍。到实验结束时，与对照组相比，当前的喂食器显着减少了蓝细菌的生物量，而埋伏喂食器则没有。在为期一周的实验中，由于前者的数量减少，当前的饲养者从放牧可食的猎物转向了蓝细菌。
4. 与预期相反，到实验结束时，co足类都没有促进蓝细菌的优势。这是因为两个放牧者，特别是当前的饲养者，最初都增加了，但随后减少了蓝细菌对浮游植物总生物量的相对贡献。此外，两个co足类均通过c减少了蓝细菌细丝的长度 。70％
5. 当缩短的细丝的数量超过食用猎物的数量时，当前的饲养者可以从食用猎物转换为蓝细菌。尽管对于当前的co足类动物浮游植物的自上而下的调节可能更强，但埋伏期的co足类动物在开花期间可以通过缩短蓝细菌细丝而发挥重要作用。因此，对co足类摄食性状进行对比在浮游植物群落中的广泛作用值得进一步研究。