Abstract We examined seasonal succession in a phytoplankton and mesozooplankton community in open coastal waters with frequently occurring harmful algal blooms. Chlorophyll a (Chl a) concentration was positively related to the N/P/Si ratio, suggesting that nitrate is a major limiting nutrient for phytoplankton biomass increase. Heterotrophic red Noctiluca, but not toxic dinoflagellate, abundance showed a negative trend with both Chl a and mesozooplankton abundance. The phytoplankton community showed a clear seasonal succession, with an increased abundance of dinoflagellates in the summer community (June–September), which was distinctive from the autumn–winter–spring community (October–May) that was dominated by diatoms. A mesozooplankton community shift followed, with a lag of a couple of months, in the late August to December community that was associated with subtropical copepods. The other community from February to August is associated with marine cladocerans. Although the most dominant mesozooplankton of year was copepod at a rate of over 70%, coexisting gelatinous plankton such as appendicularians and Noctiluca, which may compete with copepods for prey could affect to copepod production in the region.

中文翻译：

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藻华频繁发生的沿海地区浮游植物和中型浮游动物群落的演替

摘要 我们研究了经常发生有害藻华的开阔沿海水域中浮游植物和中型浮游动物群落的季节性演替。叶绿素 a (Chl a) 浓度与 N/P/Si 比呈正相关，表明硝酸盐是浮游植物生物量增加的主要限制性营养素。异养红色夜光藻，但不是有毒的甲藻，丰度显示出与叶绿素 a 和中型浮游动物丰度的负趋势。浮游植物群落表现出明显的季节性演替，夏季群落（6-9月）甲藻丰度增加，这与以硅藻为主的秋-冬-春季群落（10-5月）不同。中型浮游生物群落随之发生转变，滞后了几个月，在与亚热带桡足类相关的 8 月下旬至 12 月群落中。2 月至 8 月的另一个群落与海洋枝角类动物有关。虽然一年中最主要的中型浮游动物是桡足类，比例超过70%，但共存的胶状浮游生物如附肢和夜光藻可能与桡足类竞争猎物，可能会影响该地区桡足类的生产。