Abstract:

Jiaozhou Bay is a semi-enclosed bay at the southern shore of Shandong Peninsula and has abundant macrobenthic species. In present study, the seasonal variation of the macrobenthic community in this bay was analyzed based on data collected from four cruises in February (winter), May (spring), August (summer) and November (autumn) of 2014. A total of 199 macrobenthic species were identified, of which, 79 species were Polychaeta, 47 were Crustacea, 40 were Mollusca, 17 were Echinodermata, and the remaining 16 species belong to other animal groups. The composition of dominant species seasonally varied, however, most of them were species belong to Polychaeta. The average abundance of the macrobenthos from the four cruises was 209.85 ind./m², with the highest abundance found in the autumn cruise and the lowest in the spring cruise. The average biomass from the four cruises was 79.22 g/m², with the highest biomass found during the summer cruise and the lowest found during the spring cruise. The Shannon-Wiener index (H') of the macrobenthic community varied from 2.16 to 2.86, the species richness index (D) varied from 2.79 to 3.72 and the species evenness index (J) varied from 0.58 to 0.82. The Bray-Curtis similarity cluster analysis and NMDS ordination analyses indicated that the similarity among macrobenthic community groups was low and the distribution pattern of microbenthic animal groups showed seasonal characteristics. In recent years, with the rapid economic development of coastal zones and the continuous impact of human activities, the stability of the benthonic community in Jiaozhou Bay is threatened, therefore, long-term monitoring is recommended and effective comprehensive management measures need to be explored to result in the healthy and sustainable development of the marine ecosystem in Jiaozhou Bay.

Key words: Jiaozhou Bay, benthic macrofauna, biodiversity, community structure