Biodiversity of Free-Living Marine Nematodes in the Southern Yellow Sea,China

Biodiversity pattems of free-living marine nematodes were studied using specific, taxonomic and phylogenetic diversity measures in the southern Yellow Sea, China. The results showed that the average of Shannon-Wiener diversity index （H＇） in the study area was 3.17. The higher values were distributed in the east part of Shandong coastal waters and north part of Jiangsu coastal waters, while the lower values were distributed in the southern Yellow Sea Cold Water Mass （YSCWM）. The average of taxonomic diversity （A） was 62.09 in the study region. The higher values were distributed in the transitional areas between the coastal areas and the southem YSCWM, while the lower values were distributed near the north part of Jiangsu coastal waters and the YSCWM. Results of correlation analysis of species diversity and taxonomic diversity showed that some of the two kinds of diversity index were inde- pendent, which suggested that combining the two kinds of diversity indices can reflect the ecological characteristics better. A test for 95% probability funnels of average taxonomic distinctness and variation in taxonomic distinctness suggested that Station 8794 （in the YSCWM） was outside of the 95% probability funnels, which may be due to the environmental stress. Results of correlation analysis between marine nematodes biodiversity and environmental variables showed that the sediment characteristics （Mdo and Silt-clay fraction） and phaeophorbide a （Pha-a） were the most important factors to determine the biodiversity patterns of marine nematodes.

长江口及南黄海水域春季生物摄食生态的稳定同位素研究

根据长江口及毗邻南黄海水域多种生物的碳稳定同位素比值,计算其摄食生态类型,结果表明,一些生物的摄食生态类型计算结果存在时空与计算方法差异,其原因是生物的食性存在季度或年际上的时间变化,并会随栖息环境的变化而相应发生改变;统一稳定同位素法与胃含物分析法计算生物摄食生态的判断类型后,2种方法计算的结果基本一致,24种共有生物有21种生物的判断结果一致,推断稳定同位素法计算生物摄食生态类型可行。