Population structure of Schima superba in Qingliangfeng National Nature Reserve

The population structure and spatial distribution patterns of Schima superba on 1 hm² permanent sample plot located at Qingliangfeng Nature Reserve were analyzed by measuring, registering, tagging, identifying and mapping all the trees with DBH ≥ 1 cm in the 1 hm² permanent sample plot. The result indicated the percentage of Schima superba with DBH ≤ 5 cm and DBH > 27.5 cm was 80.5%, 8.4%. With self-renewal ability, the population was stable. Based on analysis of population size class structure, the trend of population density of Schima superba changing with individual DBH was similar to skew normal distribution. Possibly attributed to the choice of plot, Schima superba, distribution of which took on obvious spatial heterogeneity, mostly gathered at slope and ridge. The analysis of population spatial association indicated there was negative correlation between individuals with DBH ≥ 16.1 cm and those with 1 cm ≤ DBH < 16.1 cm at scales ≤ 8 m, and no correlation at larger scales. Importance values of Schima superba in 25 little plots were 0-34.35%, and the average was 8.24%. The great difference among little plots was due to aggregation of spatial distribution of Schima superba.