秦山核电站邻近水域浮游植物的研究

Studies on the phytoplankton in the waters adjacent to Qinshan Nuclear Power Station

1989年4月(春)、7月(夏)、10月(秋)和1990年1月(冬)四个季度月,对秦山核电站邻近水域23个测站的浮游植物进行了生态调查研究。共鉴定浮游植物145种(包括变种和变型),其中硅藻类44属138种,甲藻类2属2种,蓝藻类1属2种,绿藻类1属3种。在这些种类中,海水种72种,半咸水种47种,淡水种26种。测区四季均占优势的种类有中肋骨条藻、琼氏圆筛藻、蛇目圆筛藻和星脐圆筛藻等。浮游植物细胞密度以秋季最高,平均为2587×10~3个/m^3,其次为冬、春两季,平均密度分别为2209×10~3个/m^3和2117×10~3个/m^3;夏季平均密度相对较低,为1047m×10~3个/m^3。测区营养盐含量丰富,通常不成为浮游植物繁殖生长的限制因子。浮游植物的种类组成、数量分布和群落结构的变化,主要取决于降雨、光照等气象条件和海流、温盐等水文化学条件的变化。

The ecological investigations of the phytoplankton were carried out in the waters adjacent to Qinshan Nuclear Power Station in the spring, summer and autumn of 1989 and in winter of 1 990. 145 species, varieties and forma of phytoplankton which belong to 44 genera in Bacillariophyta (1 38species), 2 genera in Pyrrophyta (2 species), 1 genus in Cyanophyta (2 species) and 1 genus in Chlorophyta (3 species) were identified respectively. Among these species, marine species (72) , brackish species (47) and freshwater species (26) make up 49.66%, 32.41% and 17.93% of the total species respectively. The dominant species throughout the year are Skeletonema costatum, Coscinodiscus jonesianus, C. arqus and C. axleromphalus.The mean cell density of phytoplankton was highest in autumn ( about 2587 × 103cells/ m3), secondary in winter (2209 × 103cells/m3) and spring (2117 × 103cells/m3), lowest in summer (1047 × 103cells/m3) Nutrient concentrations of all the waters have not affected free growth of phytoplankton , the salinity decreased in summer because of rainy period and flood water, so that the changes of phytoplankton species compositions and community structures have taken place, cell densities were limited , freshwater species have increased, but marine and brackish water species have decreased greatly.