摘要: |
2011-2017年,每月一次,通过对獐子岛海域29个站位浮游甲藻的调查,探究浮游甲藻种群结构的年际变化特征。发现了浮游甲藻19属47种,其中原多甲藻属(Protoperidinium)种类最多为17种,鳍藻属(Dinophysis)和角藻属(Ceratium)各4种,裸甲藻属(Gymnodinium)和原甲藻属(Prorocentrum)各3种,膝沟藻属(Gonyaulax)和环沟藻属(Gyrodinium)各2种,原角藻属(Protoceratium)、夜光藻属(Noctiluca)和凯伦藻属(Karenia)等均为1种。浮游甲藻种类数呈逐年递增,季节上呈现夏季和秋季较多,春季次之,冬季最少。浮游甲藻密度变化区间为(2.376-339.323)×104/m3,平均密度为65.479×104/m3,亦呈现夏季和秋季较高,春季次之,冬季最低,但密度呈逐年递减,且不同站位间差异较大。调查期间,不同季节优势种类有相同性,如三角角藻(Ceratium tripos)、梭角藻(Ceratium fusus)和亚历山大藻(Alexandrium sp.)为四季优势种,但亦有差异,如鳍藻(Dinophysis spp.)和夜光藻(Noctiluca scintillans)为夏季和秋季优势种,网状原角藻(Protoceratium reticulatum)为冬季和春季优势种。优势种中有毒微藻呈逐年增多趋势,有毒的链状裸甲藻(Gymnodinium catenatum)、米氏凯伦藻(Karenia mikimotoi)和具尾鳍藻(Dinophysis caudata)等非优势种在獐子岛海域首次发现。浮游甲藻群落的香农-威纳指数、丰富度指数、均匀度指数均为秋季 > 夏季 > 春季 > 冬季,呈逐年递增趋势。近年来,獐子岛海域浮游生物群落甲藻化和有毒化趋势明显,可能与海水营养盐比例失衡、海水酸化、北黄海冷水团、双壳贝类大规模养殖等有关。 |
关键词: 獐子岛海域 甲藻 有毒微藻 种群结构 年际变化 |
DOI:10.11693/hyhz20180700187 |
分类号:Q178.53 |
基金项目:国家重点研发计划资助,2017YFC1404303号,2016YFF0201104号;国家自然科学基金资助,41576120号,41276099号 |
附件 |
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STUDY ON THE INTERANNUAL VARIATION OF PLANKTONIC DINOFLAGELLATES AND TOXIC MICROALGAE IN THE SEA AREA AROUND THE ZHANGZI ISLAND, NE CHINA |
GONG Chang-Bao1,2, FENG Zhi-Quan1,2, WANG Li3, LIANG Yu-Bo1,2
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1.National Marine Environmental Monitoring Center, Dalian 116023, China;2.Dalian Phycotoxins Key Laboratory, Dalian 116023, China;3.School of Aquaculture and Life, Dalian Ocean University, Dalian 116023, China
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Abstract: |
Monthly surveys of planktonic dinoflagellates were conducted in 29 stations around the Zhangzi Island, Dalian, NE China in 2011-2017, based on which the interannual variation of the community structure was studied using dominance species, Shannon-Weiner index, richness index, and evenness index. The interannual variation trend and horizontal distribution characteristics of toxic microalgae were analyzed. Forty-seven species in 19 genera of planktonic dinoflagellates were found, including 17 species of Protoperidinium, 4 species of Dinophysis and Ceratium, 3 species of Gymnodinium and Prorocentrum, 2 species of Gonyaulax and Gyrodinium, 1 species of Protoceratium, Noctiluca, Karenia and so on. The number of species is the largest in summer and autumn, followed by spring, and the smallest in winter. The number of species increased year by year. The density of planktonic dinoflagellates ranged from 2.376×104cell/m3 to 339.323×104cell/m3, in average of 65.479×104cell/m3; it was also the highest in summer and autumn, followed by spring, and lowest in winter but the density decreased year by year in a big difference among stations. During the seven-year study period, the dominant species in different seasons were the same, such as Ceratium tripos, Ceratium fusus, and Alexandrium spp but also had exceptions, such as Dinophysis spp and Noctiluca scintillans being the dominant species in summer and autumn, Protoceratium reticulatum being the dominant species in winter and spring. Toxic microalgae in the dominant species increased year by year. Toxic non-dominant species such as Gymnodinium catenatum, Karenia mikimotoi, and Dinophysis caudata appeared in the study area for the first time. The values of the Shannon-Weiner index, richness index, and evenness index of the community were in the order of autumn > summer > spring > winter, and showed an increasing trend year by year. A trend of pyrocystification and toxicity of plankton community in the waters of the Zhangzi Island was obvious, which might be related to the imbalance among the nutrients proportion in seawater, the acidification of seawater, the input of Cold Water Mass in the North Yellow Sea, and the large-scale culture of bivalve shellfish in the adjacent waters of the Zhangzi Island. |
Key words: Zhangzi Island dinoflagellate toxic microalga community structure interannual variation |