Individual Species-area Relationship In A Deciduous Broadleaved Forest In Baotianman Of Henan Province

The Individual Species Area Relationship (ISAR) method can be used to estimate the effects (accumulator, repeller, or neutral) of individual species on neighborhood biodiversity at different spatial scales. Systematic research is needed to make a better understanding of biodiversity, although a few researches have been analyzed the effect of focal species with different DBH classes on neighborhood biodiversity using the ISAR. Here we use nine types (all to all, all to adult, all to young, adult to all, adult to adult, adult to young, young to all, young to adult and young to young) in the25ha deciduous broadleaved forest in Baotianman National Natural Reserve in Henan Province to test following hypotheses:(1) The adult individuals (DBH>10cm) have greater influence on neighbor biodiversity than the young (DBH<10cm);(2) The individuals of same species or same size class have greater influence on neighbor young tree diversity than adult tree diversity;(3) Most focal species are neutral in the forest community of Baotianman;(4) There was obviously correlation between spatial pattern distribution and diversity maintenance of most focal species. The results were below:1) Scale dependent structures the spatial diversity of BTM25ha forest dynamic plot. Accumulator woody species dominate at the spatial scales of1-23m absolutely, whereas neutral species dominate at scales of23-50m.2) The individuals of the same species or same size class have different influence on neighbor diversity of young tree and adult tree. The young tree has greater quantity of accumulator than adult tree at small and middle spatial scales.3) The individuals of distinct size class have significant different influence on neighbor tree diversity. The young tree has greater influence on neighbor tree diversity than adult tree species at small and middle spatial scales.4) Most of studied species were aggregated, very few species were distributed randomly, and no species were regular distribution at all studied scales(0-50m). 5) Individual with different development stages had significant divergence in spatial distribution at small scales. The adult tree has more ratio of random distribution than young tree at small scales.6) There was significant correlation between the number of species randomly distributed and the number of repellers calculated by ISAR at small scales.7) The niche theory and neutral process were coupled and structured the pattern of local spatial diversity together in the deciduous broadleaved forest of Baotianman.It would be interesting to expand our analysis in other forest dynamic plots to find out if and to what extent the results are reasonable.