南海大鹏湾甲藻孢囊分布研究

DISTRIBUTION FEATURES OF DINOFLAGELLATE CYSTS IN DAPENG BAY

甲藻及其它赤潮生物孢囊被认为是赤潮发生的种源，其分布特征是赤潮发生预测的重要依据。本研究对南海大鹏湾赤潮发生密集海区底泥进行了采集分析。在调查的12个站位中，共发现甲藻抱囊29种，针抱藻抱囊1种，其中以锥状斯氏藻（ScriPPsiellatrochoidea）为最优势种，多边膝沟藻（GonyaulaxPolyedra）、褐色原多甲藻（ProtoPerdiniumavellana）和塔马亚历山大藻（Alexandriumtamarense）为优势种。抱囊的水平分布以水深最深的S2和水流最缓的S4两站位抱囊的种类、数量最为丰富，且两站位的营养盐含量高于其他站位。对抱囊的垂直分布的调查显示，大多数生活抱囊集中于NP和活性磷酸盐丰富的0-5cm底泥中，5cm以下抱囊数量骤减。根据样品中各类抱囊的比例与分布特征，对大鹏湾水域抱囊形成、沉降、水底运动和分布机制进行了推测。

The species and distribution of the cysts of dinonagellates and other organisms inDapeng Bay, the South China Sea, was investigated in March 1992 at 12 sites bycollecting the sediments on sea-bed. From cysts of 30 species found, Scrippsiella trochoideawas the most dominant one at all sites investigated, and Gonyaulax polyedra, Protoperidiniumavellana and Alexandrium tamarense were common species. It was found that highest cystabundance was in sediment at site under deep water and in sediment at site where waterflow was stable. Most of the living cysts accumulated in sediment layer at 0-5 cmwith high phospate concentration and low N/P value. On the basis of the distributionof cysts of different species, the possible outbreak of red tide is disccussed.