Interspecific relationship of dominant populations in relict deciduous forests on Mount Tianmu,Eastern China

Relict plants are an important component for protection and restoration of biodiversity in a region. To explore the symbiotic relationship and coexistence mechanism of evergreen,deciduous and coniferous trees in a relict deciduous forest of the National Nature Reserve of Mount Tianmu,Zhejiang,China,their floristic composition and community structure have been surveyed in 196 plots.The interspecific association,interspecific correlation,and niche breadth were determined using a correlation analysis and niche breadth analysis. Results indicated that species pairs with significant(P0.05) and highly significant(P0.01) differences accounted for 20.77%;whereas pairs that were negatively correlated comprised of 55.85%.The interspecific relationship among relict broadleaf tree species was significantly and negatively correlated with a mutually exclusive spatial distribution.The interspecific relationship between long-lived relict deciduous tree species,such as Nyssa sinensis,Liquidambar acalycina,Liquidambar formosana,or Emmenopterys henryi,and other deciduous tree species was significantly and negatively correlated,but was significantly and positively correlated with evergreen broadleaf tree species.Thus,relict deciduous tree species with tall stature were coexisted with other deciduous broadleaf tree species at succession serial and with evergreen broadleaf tree species at vertical spatial scale.