Abstract:The aim was to understand the relationship among dominant species in secondary forest of Zhoushan islands. Based on investigation of 1 hm2 fixed plot in Taohua island, the niche characteristic and interspecific association of 15 dominant species were studied. The results showed that the niche breadth of Litsea coreana var. sinensis, Machilus thunbergii, Mallotus japonicus were broader than other species, with Levins and Hurlbert' niche breadth values of 1.3563, 1.3170, 1.3097 and 0.8572, 0.7373, 0.7154, respectively, while Celtis sinensis, Maclura tricuspidata, Cornus macrophylla had narrow niche breadths. There were 39 species pairs with niche proportional similarity more than 0.5, accounting for 37.1% of the total pairs. The broader niche of two species has, the bigger of their niche proportional similarity is. The species with broad niche could have big niche overlap with another species with narrow niche. On the contrary, the species with narrow niche could have low niche overlap with another species with broad niche. There were not significant negative associations overall among 15 dominant species. The X2 test and association coefficient showed that species pairs with negative association were more than that with positive association. Therefore, the interspecific association of dominant species in secondary forest of Zhoushan islands was relatively loose with certain independent at low extent. The community was not mature and in the unstable stage of dynamic succession. The pioneer species Ficus erecta was in decline stage. The secondary forest will gradually recover to zonal evergreen broad-leaved forest, which is dominant by Litsea coreana var. sinensis and Machilus thunbergii.
