连云港田湾核电站邻近海域网采浮游植物群落的变化

根据2011年5月、2012年8月和2013年8月在连云港田湾核电站邻近海域进行的调查,研究了网采浮游植物的种类组成、年际变化及其与环境因子的关系。该海域共鉴定出浮游植物8门160种,其中硅藻种类数最多(113种),甲藻其次(31种),蓝藻、金藻、黄藻、绿藻、裸藻和隐藻偶有检出。优势种共8种,包括7种硅藻和1种甲藻。相关性分析表明,浮游植物细胞丰度与磷酸盐、亚硝酸盐和温度呈显著正相关,与盐度呈负相关。结合历史数据分析表明,近30年来核电站邻近海域营养盐结构已发生较大变化,表现为硝酸盐浓度急剧升高,由1983年的0.70μmol/L升至2013年的29.38μmol/L,N/P由4.9∶1升至53.7∶1。同时浮游植物群落也有较大变化,表现为优势种呈角毛藻Chaetoceros spp.向骨条藻Skeletonema spp.演替的趋势。

Changes of Net - collected Phytoplankton Community in Sea Area Adjacent to Tianwan Nuclear Power Plant of Lianyungang

The net -collected phytoplankton in the sea area adjacent to Tianwan Nuclear Power Plant of Lianyungang was in- vestigated in May 2011, August 2012 and August 2013, and their species composition, annual changes and relations with environ- mental factors were studied. A total of 160 phytoplankton species in 8 phyla were identified, including 113 diatom species, 31 dino- flagellate species and other 18 taxonomic （Chlorophyta, Chrysophyta, Euglenophyta, Cyanophyt, Xanthophyta and Cryptophyta） species. Dominant species consisted of 7 diatom species and 1 dinoflagellate species. The correlation analysis showed that the cell density of phytoplankton was significantly positively correlated with phosphate concentration, nitrite concentration and temperature, and was negatively correlated with salinity. Since the year 1983, the structure of nutritive salt in the studied sea area has changed obviously： the concentration of phosphate sharply increased from 0.70 μmol/L in 1983 to 29.38 μmol/L in 2013 ; the ratio of N to P also increased from 4.9：1 in 1983 to 53.7：1 in 2013. Meanwhile, the structure of phytoplankton community has also experienced an obvious variation since 1983, and the dominant species Chaetoceros spp. was gradually replaced by Skeletonema spp.