| 摘要: |
| 于1990年6月在长江口赤潮多发区定点观测到一次中肋骨条藻赤潮发生的全过程，对中肋骨条藻赤潮发生过程中浮游植物群落结构的变动及细胞形态的变化进行研究。结果表明，（1）中肋骨条藻赤潮发生前，水体中甲藻数量多于硅藻；赤潮发生后，中肋骨条藻增殖，逐渐成为主要优势种，硅藻在数量上超过了甲藻；浮游植物种类丰度指数的大小能较好地反映赤潮发生的各个阶段。（2）赤潮发生过程中，中肋骨条藻细胞增殖率次序为：发展阶段＞维持阶段＞起始阶段。（3）在赤潮发生的维持阶段后期和消亡阶段，有5％ - 7.8％的中肋骨条藻形成休眠孢子，一个中肋骨条藻细胞仅形成一个休眠孢子，且同一个中肋骨条藻群体链上的所有细胞形成休眠孢子是同步的。 |
| 关键词: 中肋骨条藻 浮游植物群落结构 增殖率 休眠孢子 细胞形态 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金重大项目，9389008号 |
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| INVESTIGATION REPORT ON THE SKELETONEMA COSTATUM RED TIDE IN CHANGJIANG RIVER ESTUARY— STUDY ON THE PHYTOPLANKTON COMMUNITY COMPOSITION AND CELL MORPHOLOGY |
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Shen Hong, Hong Junchao
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East China Sea Monitoring Center, SOA, Shangha, 200137
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| Abstract: |
| Study on the variantion of phytoplankton community composition and cell morphology in the Skeletonema costatum red tide that occurred in the Changjiang River Estuary in June, 1990 showed that: (1) the biomass of Pyrrophyta was greater than that of Bacillariophyta before the occurrence of Skeletonema costatum red tide, after which occurrence Skeletonema costatum proliferated and gradually because the dominant species, and the biomass of Bacillariophyta became greater than that of Pyrrophyta. The difference of community diversity of phytoplankton was reflected in all stages of the Skeletonema costatum red tide. (2) The cell proliferating rate of Skeletonema costatum was in the order: developing stage > sustaining stage > starting stage. (3) 5 - 7.8 percent of Skeletonema costatum cells became resting spores during the sustaining later stage and vanishing stage of red tide. A Skeletonema costatum cell only formed_ one resting spore. All cells of the Skeletonema costatum chain synchronously formed resting spores. As adaptation to the environment, some Skeletonema costatum cells transformed to resting spores during the later period of red tide when nutrition became deficient and environmental conditions worsened (rainstorm). |
| Key words: Skeletonema costatum, Phytoplankton community composition, Proliferating rate, Resting spores, Cell morphology |
