大鹏湾盐田水域反曲原甲藻数量的时空变化特点

THE SPATIO-TEMPORAL VARIATIONAL CHARACTERISTICS OF PROROCENTRUM SIGMOIDESIN YANTIAN WATERS, DAPENG BAY

对１９９０年３月３０日－５月５日广东大鹏湾盐田水域反曲原甲藻Ｐｒｏｒｏｃｅｎｔｒｕｉｎｓｉｇ－ｍｏｉｄｅｓＢｏｈｍ进行研究。详细分析了反曲原甲藻数量的时空变化及分布特点。多元回归分析表明：影响反曲原甲藻数量变化的环境因子，表层主要是亚硝酸氮，而底层仅与盐度相关。４月２０日盐田水域发生赤潮，经水样分析，发现表层水体中反由原甲藻数量很高（大于３００个·ｍｌ（－１）），占浮游植物数量的８６％以上。由此说明，反曲原甲藻是此次赤潮的原因种之一。本种通过扫描电子显微镜观察和分析所确认，并作了形态特征描述。

In recent years, there were frequent occurences of red tide in Yantian waters of Dapeng Bay, Guangdong Province. Many red tide organisms were found in that water area from March 30 to May 5, 1990. The study emphasizes on morphological structures,spatio-temporal changes and distributive characteristics of Prorocentrum sigmoides. Under SEM, the morphological structures of P.. sigmoides are similar to those observed by Toriumi (1980), and identical in appearance to P. sigmoides as identified by Bhm (1933). Analyses showed that P. sigmoides peaked once every 10 days, with a higher amount in the bottom than on the surface, especially from 8-20, April, where highest value reached 514 cells. ml(-1). P. sigmoides had absolute superiority (93, 9%) in the whole phytoplankton population. These results demonstrated that P. sigmoides was a main red tide organism in Yantian waters, and the causative species in the red tide there (329 cells·ml(-1), 86.2% of the phytoplankton) on 20 April, 1990.