中街山列岛海域鱼卵、仔稚鱼群落结构特征及其与环境因子的关系

Community structure of ichthyoplankton and its relationship with environmental factors in Zhongjieshan islands, China

为了解中街山列岛海域鱼卵仔稚鱼空间分布、种类组成及与环境因子的关系,于2010年5月—2012年2月在中街山列岛海域利用水平和垂直拖网开展了8个航次的鱼卵、仔稚鱼调查。运用非度量多维标度排序、聚类分析和典范对应分析(CCA)等方法对该海域鱼卵、仔稚鱼的空间分布进行了综合分析。结果表明:两年水平拖网共采集到鱼卵1783粒,仔稚鱼67尾;垂直拖网共采集到鱼卵576粒,仔稚鱼59尾。2010年平拖优势种为短吻红舌鳎(Cynoglossus joyneri),垂拖重要种为鲉形目未定种(Scorpaeniformes sp.)和扁舵鰹(Auxis thazard)。2011年平拖重要种为短吻红舌鳎、鰏属未定种(Leiognathuss sp.)、龙头鱼(Harpodon nehereus)和鳀(Engraulis japonicus);垂拖重要种为短吻红舌鳎、龙头鱼和中华小公鱼(Stolephorus chinensis)。经单因子相似性分析(ANOSIM),鱼卵仔稚鱼的优势种和重要种群落物种组成存在显著差异(P<0.01)。研究结果表明,温度和盐度对鱼卵仔稚鱼的影响较大,夏季是中街山列岛海域鱼类产卵的重要时期。该海域以恋礁的小型底层鱼类为主,是褐菖鲉(Sebastiscus marmoratus)、龙头鱼等小型底层经济鱼类的重要产卵场和育幼场。

In order to understand the spatial distribution and species composition of fish eggs and larvae in Zhongjieshan Islands and their relationship with environmental factors, ichthyoplankton surveys were carried out from May 2010 to February 2012 by using the horizontal and vertical tows. The non-metric multi-dimensional scaling, cluster analysis and canonical correspondence analysis(CCA) were used to analyze the survey data. The results showed that a total of 1783 fish eggs and 67 larvae were collected in two years of horizontal tows, while a total of 576 fish eggs and 59 larvae were collected from vertical tows. In 2010, the dominant species of horizontal tows was Cynoglossus joyneri while the important species of vertical tows were Scorpaeniformes sp. and Auxis thazard. In 2011, the important species of horizontal tows were Cynoglossus joyneri, Leiognathuss sp., Harpodon nehereus, and Engraulis japonicus while the important species of vertical tows were Cynoglossus joyneri, Harpodon nehereus, and Stolephorus chinensis. ANOSIM(analysis of similarity) indicated that there were significant spatial-temporal differences in species composition between the dominant species and important species in fish eggs and larvae. The results suggested that temperature and salinity had great influence on fish eggs and larvae, and summer was an important season for fish spawning. The areas were dominated by small demersal reef fishes, which were important spawning and nursery grounds for demersal fishes such as Sebastiscus marmoratus and Harpodon nehereus.