【摘要】 利用 2 0 0 1— 2 0 0 2年 4个季度月航次调查资料 ,研究了长江口海域浮游植物的分布及其与长江径流的关系 ,共鉴定浮游植物 1 5 4种 (含变种和变型 ) ,其中属硅藻类的有 1 1 3种 ,甲藻类 36种 ,近岸低盐性的中肋骨条藻 (Skeletonemacostatum)是最重要的优势种。夏季浮游植物密集区位于长江口海域的北部及靠近浙江近海的上升流区 ,春季和秋季密集区出现在调查区的南部。浮游植物数量高峰出现在夏季 (平均为 9 2 7× 1 0 6 个 /m3) ;冬季 (枯水期 )数量最少(平均为 2 91× 1 0 5 个 /m3) ,且分布相对较均匀 ,显示出该海域浮游植物种类组成与数量的季节变化同长江径流量有明显的关系。由于大量营养盐被长江径流携带入海 ,造成河口区严重富营养化 ,这为赤潮生物大量孳生提供了适宜的环境条件 ,长江口海域已成为我国沿海赤潮多发区之一。更多还原

【Abstract】 Using data obtained from four quarterly investigations in the Changjiang Estuary during 2001 to 2002, relations between phytoplankton distribution and runoff in the Changjiang River were considered. Among the 154 species of phytoplankton(including varieties and formas)identified,113 species belonged to Bacillariophyta and 36 species to Pyrrophyta. Eurythermal and low saline species such as Skeletonema costatum were the most dominate species. During summer,the dense area of phytoplankton growth was located in the northern section of the study area and upwelling zone near the Zhejiang coast. During spring and autumn,the dense area was located in the southern section. Phytoplankton abundance peak occurred during summer(average 9 27×10 6ind/m 3). During the winter(dry season),abundance of phytoplankton was very low(average 2 91×10 5ind/m 3). The flow capacity of the Changjiang River was the major factors underpinning this seasonal variation of abundance and composition of phytoplankton. The large quantity of nutrients carried into the estuary,provided a nutrient rich environment ideal for the occurrence of red tide. Hence Changjiang Estuary has been one of the main regions experiencing the frequent red tide occurrence in China.更多还原