Intra-specific and Inter-specific Competition of Tsoongiodendron odorum in the Junzifeng National Nature Reserve of Fujian Province

In order to explore the competitive relationship and dynamic patterns among natural tree species in Tsoongiodendron odorum community,a survey was conducted on 6 typical plots of Tsoongiodendron odorum communities from July to August 2021 in the Junzifeng National Nature Reserve of Fujian.The Hegyi competition model was used to analyze the intra-species and inter-species competition indices of 52 objective trees and 686 accompanying competing trees in the Tsoongiodendron odorum community of the Junzifeng National Nature Reserve of Fujian,at the same time,regression analysis was used to establish a correlation function model for the competition intensity between the target trees,stands,and species.The results showed that the intra-species and inter-species competition indices of Tsoongiodendron odorum were 37.64% and 62.36%,respectively,indicating that competition mainly comes from inter-species.There were many accompanying tree species of Tsoongiodendron odorum and the order of competition between Tsoongiodendron odorum and the main accompanying tree species was as follows:Alniphyllum fortunei＞Castanopsis fargesii＞Castanopsis carlesii＞Litsea subcoriacea＞Schima superba＞Machilus chekiangensis＞Quercus pachyloma＞Ilex qingyuanensis＞Meliosma squamulata＞Castanopsis lamontii.The competition intensity decreases with the increase of the DBH of objective trees.When the DBH of objective trees were more than 30 cm,the change in competition intensity was small and tends to be stable.The relationship between competition intensity and DBH accords with a power function (CI=aD^b),and the intra and inter-species competition intensity of objective trees can be accurately predicted using corresponding models.According to the results predicted by the model,when the diameter at breast height of the objective tree was less than 30 cm,appropriate treatments such as pruning and selective cutting can be used to adjust the interspecific relationship between the objective trees and the competitive trees,which was beneficial for better protecting the competitive tree species.