To compare the macrobenthic community composition,community structure,and inter-annual variation inside / outside the Yellow Sea Cold Water Mass Core (YSCWMC) in summer,we analyzed the data collected in three marine surveys in July 1959,June 2004,and August 2012 in 18 stations.Three stations within and beyond the YSCWM were selected in each survey.Biodiversity indices including Shannon-Wiener index (H′),Pielou index (J′),Margalef index (d),and average taxonomic distinctness index (△+) were applied.Variation in taxonomic distinctness index (A +) and abundance-biomass comparison (ABC) curves were used to determine the status of the community.In the three surveys,altogether 33/87 species were found in/out of the cold-water mass.Two-way ANOVA analysis shows no significant differences in H′,J′,and d,as well as in abundance and biomass,in spatial and temporal realms in or out of the YSCWMC.The variation in community component was slightly greater in the inside than the outside,which is also true as shown in ABC curve.Mollusks were obviously more abundant inside than outside in biomass with very little change in species composition.Polychaeta and Echinodermata were major contributor to biomass but very few in variety inside the core,while in the outside,they dominated in both biomass and variety.Mollusks occupied 38％ of the total biomass inside but only 3％ outside.Thyasira tokunagai,Raetellops pulchella,Bivalvia,Nuculanida,and Portlandia japonica were main and common species inside the water mass.Therefore,YSCWMC could provide a favorable condition for mollusk growth and propagation,also maintain the its community structure.

通过对2011-2013年夏季南黄海大型底栖软体动物的群落结构进行分析,揭示其与黄海冷水团之间的关系.使用Shannon-Wiener指数(H')、Pielou指数(J')、Margalef指数(D)和ABC(AbundanceBiomass Comparison)曲线法分析群落多样性和稳定性.使用PRIMER6.0对大型底栖软体动物群落进行Cluster和MDS相似性分析.通过单因素方差分析(ANOVA)检验各指数之间的差异性.结果表明,三个航次共获得大型底栖软体动物36种,日本梯形蛤(Portlandia japonica)与薄索足蛤(Thyasiratokunagai)在三年中均为优势种.大型底栖软体动物平均丰度分别为27.250±22.15、31.765±27.948和30.476±30.818 ind./m2;平均生物量分别为8.164±9.145、6.942±7.139和5.071±10.015 g/m2.研究结果显示3年来黄海冷水团内大型底栖软体动物的多样性高于冷水团外大型底栖软体动物多样性,丰度分布由北到南逐渐增加且冷水团内的丰度大于冷水团外的丰度.南黄海海域大型底栖软体生物群落结构稳定,与2006年相比没有较大的变化.

To explore the characteristics of a macrozoobenthic community in the sea adjacent to the Yangtze River estuary during the wet season, macrozoobenthic samples were collected during June, August, and October, 2012, and data were analyzed using statistical methods including Two-Way ANOVA, Cluster analysis, Non-metric Multidimensional Scaling (NMDS), and Abundance-Biomass Comparison Curves (ABC Curves). A total of 181 macrozoobenthic species were recorded, with 82 species of Polychaeta, 46 Crustacea, 31 Mollusca, 11 Echinodermata and 11 species belonging to other groups. The abundance, biomass, Margalef’s richness index (d), Shannon-Wiener index (H'), and Pielou index (J') did not show any significant temporal or spatial differences except that J' in the offshore area was significantly higher than that found in the inshore area. Three to four macrozoobenthic assemblages were identified using the 20% similarity level and a low similarity level among stations was also observed. ABC curves revealed that the macrozoobenthic community in the offshore area was less disturbed than that in the inshore area. As a result of the continuous impact of anthropogenic activities, the macrozoobenthic community was severely disturbed and unevenly distributed in the sea adjacent to the Yangtze River estuary.

[Objective]This research was aimed to give insight into the macrofaunal community structure in the South Yellow Sea and to provide scientific foundation for ecological environment protection in future.[Methods]Based on the samples collected in the South Yellow Sea during June,August and October,2012,the macrofaunal data were analyzed by using cluster analysis (CLUSTER ),non-metric multi-dimensional scaling (nMDS),one-way analysis of similarity (One-way ANOSIM)and similarity percentages (SIMPER ) methods.[Results]CLUSTER and nMDS showed that the macrofauna could be classified into 4~5 groups on the 20% similarity level.One-way ANOSIM analysis revealed that the macrofaunal communities among three months were significantly different in the South Yellow Sea.SIMPER analysis uncovered that the dominant species in different groups were also different,with Echinodermata and Mollusca dominated the community in the Yellow Sea Cold Water Mass and Polychaeta in others.[Con-clusion]Compared with previous reports,the macrofauna in the South Yellow Sea had changed drastically for over half a century,and were classified into three communities,i.e.,the Yellow Sea Cold Water Mass community,the mixed community and the eurythermal community.Echi-noderm Ophiura sarsii vadicola replaced Mollusca and Crustacea as the most dominant species in the Yellow Sea Cold Water Mass community.Polychaeta replaced Echinodermata and Mol-lusca as the dominant species in the mixed community and the eurythermal community.

Based on the material collected during December,2006 to November,2007 from three sampling stations representing respectively the high,middle and low tidal zones,the macrobentic community and its seasonal changes of the intertidal zones of Xicun village,Rushan County,near to the mouth of the Rushankou Gulf,South coast of Shandong Peninsula,are reported in the present paper.The results show that the total mean abundances,biomasses and species numbers of macrobenthos in this intertidal zone are respectively 103.33 ind/m2,7.056 g/m2 and 41 species;those from the high tidal zone(Station R1) are 72 ind/m2,0.64 g/m2 and 21 species;from the middle tidal zone(Station R2) are 115 ind/m2,8.584 g/m2 and 29 species;and from the low tidal zone(Station R3) are 123 ind/m2,11.943 g/m2 and 12 species,respectively.The mean abundances,biomasses and species numbers of the macrobenthos in three tidal zones are distinctly different,of which the mean abundances are R3R2R1,mean biomasses are R3R2R1,species numbers are R2R1R3.Those ecological characters,which are affected by substratum,tide,season and human activity,are different from those of the estuary of the Yellow River in the Bohai Gulf and Jiaozhou Bay west to the Rushankou Gulf along the south coast of the Shoudong Peninsula.This study can help to understand the way of the fishboats and other boats affecting macrobenthic community,and also offer basic data to further research.

Three sampling stations within intertidal zone of Hongshiya, Jiaozhou Bay, were set up to explore the community of macrobenthos in Jiaozhou Bay during August 2003 to May 2004 in four seasons. The results show that the total mean density, biomass and species number of macrobenthos in this intertidal zone are 718.67 ind./m2, 123.21 g/m2 and 62 species respectively; those from the high tidal zone (station H1) are 1765.5 ind./m2, 342.53 g/m2, 12 species, those in the middle tidal zone (station H2) are 248 ind./m2, 11.31 g/m2, 35 species, and those in the low tidal zone (station H3) are 142.5 ind./m2, 15.74 g/m2 and 44 species, respectively. The mean densities, biomasses and species numbers of the macrobenthos in three tidal zones are distinct different, of which the mean densities are H1H2H3, mean biomasses are H1H3H2, species numbers are H3H2H1. While the quantitative collection, qualitative collection was also carried out and 44 species were obtained, of which 27 species were not collected during the quantitative collection. There are 89 species in total were collected from Hongshiya intertidal zone.

Field research of macrobenthic fauna at 10 stations in Jiaozhou Bay was carried out seasonally from February of 1998 to November of 1999. There were fewer species and the indices of biodiversity (Shannon-Wiener index) were lower in Stations 2, 3, 7 and 9 than in other stations. Stations 2 and 3 were situated in the inner area near Cangkou, a heavily polluted area. Stations 7 and 9 were situated at the mouth of the bay, where the bottom sediment was coarse sand. The indices in Stations 1 and 6, where the bottom sediment was soft mud, were high. The average Shannon-Wiener index of all the 10 stations was lower in 1999 than in 1998, although the difference was not remarkable. In both of the two years, the average Shannon-Wiener indices were lower in spring and autumn than in winter and summer; Pielou’s evenness index was highest in summer and lowest in spring; and the species richness index was slightly higher in winter and slightly lower in autumn. The relationship between biodiversity of the macrobenthos in Jiaozhou Bay and human activities should be studied further.