关键词: 岩相潮间带, 底栖生物, 南日岛, 生物量, 栖息密度, roky interdidal zone, benthos, Nanri Island, Biomass, Inhabit density

Abstract: A survey on two rocky intertidal sections in Dongdai village of Nanri island was carried out from April 2011 to February 2012 . 73 species were identified and analyzed , including 49 species of Mollusca , 8 species of Macroalgae , 7 species of Crustacea , 6 species of Echinodemata , 1 species of Polychata , and 2 others. The average biomass of benthos in the intertidal zone was 1658.01 g/m2 , and the average inhabit density was 23420 ind./m2 . The biodiversity index varies 0.42~1.84 ; the index of Margalef’s species richness varies 0.67~1.71 ; the Pielou’s evenness varies 0.12~0.42 ; and the index of Simpson’s dominance varies 0.13~0.61 . The distribution characteristics was the result of multiple factors , including habitat , seasonality , and human activity and so on .