Abstract:To explore the habitat flexibility and competition mechanism of vegetation in Qingyunshan Nature Reserve, Wengyuan, Guangdong Province, the niche characteristics of dominant species of forest communities were analyzed. The results showed that the total importance value of 12 dominant species was 49.01, and the importance value of Cunninghamia lanceolate and variance coefficient of Phyllostachys edulis were the biggest. The variation trends of Levins and Shannon niche breadth were similar, the niche breadth of Diospyros morrisiana, Castanopsis fargesii, Schima superba, Itea chinensis and C. faberi was high, however, that of Phyllostachys edulis, Cunninghamia lanceolata, Castanopsis fissa and Machilus chinensis was low. The low niche overlap and niche similarity of all species pairs indicated that interspecific competition among coexisting species was not intense, thus the communities in Qingyunshan Nature Reserve was in a relatively stable state. The relationship between niche breadth and the importance value was insignificant, however, there was a significant negative relationship between niche width and variance coefficient of importance value, indicating that the variance coefficient of importance value might be an important influence factor on niche width. The study provides an important scientific basis for the conservation and management of forest resource in Qingyunshan Nature Reserve.