STUDY ON COMPETITION RELATIONSHIP BETWEEN DIFICATORS IN DARK CONIFER FOREST IN THE CHANGBAI MOUNTAINS

According to the field investigation data, the intraspecific and interspecific competition of Picea jezoensis in dark conifer forest in the Changbai Mountains was studied by using Hegyi's competition index model for individual tree. The results showed that intraspecific competition intensity of Picea jezoensis reduced with increase of diameter scale of trees. In the forest,the order of competition intensity is:Picea jezoensis-Picea jezoensisPicea jezoensis-Abies nephrolepisPicea jezoensis-Pinus koraiensisPicea jezoensis-Larix olgensisPicea jezoensis-Betula ermaniiPicea jezoensis-hard woods. The relationship between competition intensity and individual size of objective trees closely follows the equation CI=AD-B. Based on the equation, competition intensity in the forest is simulated. It is found that the ecosystem reaches stable stage once Picea jezoensis diameter at breast height attains more than 35 cm. At the same time, some conclusions and suggestions are proposed. It is proved that Hegyi's competition model for individual tree can provide quantitative index for research on intraspecific and interspecific relationship in plant population ecology. Fig 2, Tab 4, Ref 10