海阳市海域底栖生物种类组成及群落结构特征
Species Composition and Community Characteristics of Benthic Organisms in Marine Haiyang

通过2019年11月(秋季)和2020年5月(春季)海阳市海域两个航次的底栖生物调查，共鉴定出底栖生物62种，其中多毛类44种(71.0%)，甲壳类12种(19.4%)，棘皮动物2种(0.03%)，软体动物3种(0.05%)，纽形动物1种(0.02%)。秋季发现2种优势种，中蚓虫(Mediomastus californiensis)为第一优势种；春季发现5种优势种，独指虫(Aricidea fragilis)为第一优势种。2019年秋季底栖生物丰度平均值为432.22 ind./m²，显著低于2020年春季1271.37 ind./m² (p < 0.01)。2019年秋季底栖生物多样性和丰富度指数在近岸海域较低，均匀度指数则在近岸海域及千里岩岛邻近海域较高；2020年春季底栖生物多样性和丰富度指数在近岸海域较低，均匀度指数则在近岸海域较高。春季的多样性和丰富度指数显著高于秋季(p < 0.05)，但两季均匀度指数无显著差异(p > 0.05)。
Two cruise survey samplings of benthic organisms were conducted in the marine area of Haiyang in November 2019 and May 2020, corresponding to autumn and spring. We identified 62 species and 44 of them belong to Polychaeta, accounting for 71.0%; 12 species belong to Crustacea, accounting for 19.4%; 2 species belong to Echinodermata, accounting for 0.03%; 3 species belong to Granulifusus kiranus, accounting for 0.05%; 1 species belongs to Nemertina, accounting for 0.02%. Two species were dominant species in autumn and Mediomastus californiensis was the first dominant species. Five species were dominant species in spring and Aricidea fragilis was the first dominant species. The average abundance value of benthic organisms was 432.22 ind./m², significantly lower than the value of 1271.37 ind./m² in spring (p < 0.01). The nutrients, which affected the growth of benthic diatom and thus affected the abundance of benthic organisms, were higher in spring, because the seasonal changes may be the reason of the difference between them. In autumn 2019, Shan-non-Wiener diversity and Margalef’s richness indices of benthic organisms were lower in the coastal sea, while the Pielou evenness index was higher in the coastal waters and the waters near the Qi-anliyan islets. In the spring of 2020, the diversity and richness indices of benthic organisms were lower in the coastal waters, while the evenness index was higher in the coastal waters. The diversity and richness indices in spring were significantly higher than those in autumn (p < 0.05), but the difference of evenness index between the two seasons was not significant (p > 0.05).