甲藻孢囊在长江口海域表层沉积物中的分布

为了了解长江口海域赤潮爆发潜势，于2002年4月至5月用采泥器采集了位于122°～123．5°E、29°～32°N之间12个站位的表层沉积物，分析沉积物中甲藻孢囊的分布．共分析鉴定出孢囊类型29种，其中自养型11种，异养型18种．每个站位的孢囊种类在10～21之间，孢囊密度为11．7～587孢囊·g-1干泥之间．远岸海域孢囊种类较为丰富，密度也较高．在调查区域内，孢囊密度及种类自西向东、自北向南逐渐增加．亚历山大藻孢囊分布广泛，最高密度为40．4孢囊·g-1干泥，其他赤潮种类的孢囊如链状裸甲藻、多边舌甲藻、锥状斯氏藻、科夫多沟藻和无纹多沟藻等都在长江口海域有分布．

Distribution of dinoflagellate resting cysts in surface sediments from the Changjiang River estuary

In order to understand the potential of algal blooms, surface sediments were collected from 12 stations in the Changjiang River estuary with longitude from 122 degrees to 123.5 degrees E and latitude from 29 degrees to 32 degrees N from April to May 2002 to investigate the distribution of dinoflagellate resting cysts, 29 different cyst morphotypes representing 19 genera and 6 groups were identified. Among them, there were 11 autotrophic species and 18 heterotrophic ones. The number of species observed in each sample was low, and varied from 10 to 21. Cyst concentrations varied from 11.7 to 587 cysts per gram dry weight. Cyst concentrations and species diversity were higher in offshore areas, and increased from the west to the east, and from the north to the south within the studied area. Cysts of Alexandrium distributed widely in the Changjiang River estuary, with the maximum concentration of 40.4 cysts per gram dry weight. Cysts of harmful algal bloom causative species such as Alexandrium, Gymnodinium catenatum, Lingulodinium polyedra, Scrippsiellla trochoidea, Polykrikos kofoidii and P. schwartzii were also observed in this survey.