Abstract:

The species association of Castanopsis community in Jinggangshan Mountain Nature Reserve was analyzed in this paper. The experimental results may be useful for forest management, vegetation restoration, and biodiversity conservation in Jinggangshan Mountain Nature Reserve, and sustainable development of Jinggangshan tourist resources. In the experiment, according to the factor of altitude, 15 plots were established, each of them containing four quadrats of size 10 m×10 m. For every quadrat, one sub-quadrat of 5 m×5 m was set for shrubs and one sub-quadrat of 2 m×2 m was set for herbaceous plants. Within each quadrat, the girths, plant name, heights, and coverage of all plants (H＞5 m, DBH＞10 cm) in tree layer, and individual number, plant name, heights, and coverage of all plants of all shrub and herbaceous plants were recorded. At the same time, the environment factors—slope, altitude, thickness of soil and so on were also recorded. Based on the data from the 15 plots, the species association for 20 dominant species in Castanopsis community was analysed. The data for statistics include the species numbers of the quadrats, the quadrats numbers of species and the relations between species pairs. Regarding the index value of the measure of species association as half-matrix, according toχ2 value as constellation diagrams. Variance analysis, χ2 test, association coefficient (AC), Jaccard index and point correlation index were used to examine the species association between 20 dominant species in Castanopsis community.There were 214 species of vascular plants in the Castanopsis community in Jinggangshan Mountain (including varieties), belonging to 75 families and 132 genera, in which the pteridophyte accounted for 14 families 19 genera and 24 species, the gymnosperm 3 families, 4 genera and 4 species, and the angiosperm 58 families, 109 genera and 186 species. The community structure was complicated, which was composed of tree layer, shrub layer and herb layer. The tree layer is consisted of three sub-layers.It was found that the overall association between 20 dominant species was significantly positive. W test indicated that significantly positive correlation exists among the 20 dominant species, which suggests that the Castanopsis community is stable. Theχ2 test showed that among these 20 dominant species, 10 species pairs exhibited highly significant positive association, another 10 species pairs showed significant positive association, 4 species pairs exhibited highly significant negative association, and 8 species pairs exhibited significant negative association. Most of the total 190 species pairs did not show significant association, which may be related to the serial stage of the community and the ecological characteristics of investigated species. Based on the results, it might be inferred that the community was at a stable late successional stage.