黄海鱼类群落分类学多样性的研究

The Taxonomic Diversity of Fish Communities in the Yellow Sea

为开展不同取样区域,不同生境间和历史数据的比较研究,根据1985年和2000年秋季在黄海进行的渔业资源底拖网调查,应用分类学多样性指数从黄海、区域和局域3个空间尺度上分析了黄海鱼类群落分类学多样性的变化。在黄海尺度上,2000年等级多样性指数Δ+和分类差异变异指数∧+明显降低,而1985年的分类学多样性指数值则接近于黄海鱼类主名录的理论平均值。在区域尺度上,分类多样性指数Δ,分类差异指数Δ+在黄海中、北部较高,南黄海较低;等级多样性指数Δ+为南黄海最高,中黄海最低,其区域尺度变化主要是由鲈形目、鲽形目、鲱形目和形目种类,特别是软骨鱼类的种类数的分布变化造成的。2000年3个区域的分类学多样性指数值分别低于1985年对应值。在局域尺度上,南黄海的南部、西部和中黄海的西部以及北黄海的鱼类群落等级多样性指数Δ+远小于黄海鱼类主名录的理论平均值,仅中黄海的东部和南黄海的东部的等级多样性指数值接近理论平均值。

Based on the data from bottom trawl surveys in autumn 1985 and 2000, the taxonomic diversity and distinctness of fish communities in the Yellow Sea were examined using taxonomic diversity indices on the scale of the Yellow Sea, and on regional and local scales. On the scale of the Yellow Sea, the average taxonomic distinctness Δ+ and the variation in taxonomic distinctness ∧+ decreased significantly in 2000, whereas in 1985 their values were close to those of the Yellow Sea fish master list. On the regional scale, the taxonomic diversity Δ and taxonomic distinctness Δ* were higher in the northern and central Yellow Sea, and lower in the southern Yellow Sea. The average taxonomic distinctness Δ+ was the highest in the southern Yellow Sea and lowest in the central Yellow Sea; the spatial variations were largely caused by the different spatial distributions of species belonging to orders Perciformes, Pleuronectiformes, Clupeiformes and Scorpaeniformes, especially those of cartilaginous species. Reduced average taxonomic values in all these three regional areas were observed in 2000 compared with their corresponding values in 1985. On the local scale, the southern and western parts of the southern Yellow Sea, the western part of the central Yellow Sea and the northern Yellow Sea supported assemblages where the average taxonomic distinctness Δ+ values were much smaller than the theoretical mean. Values of taxonomic distinctness Δ+ close to or occasionally greater than the theoretical mean were only found in the eastern parts of the central and southern Yellow Sea.