Study On Management Mode For Spruce-Fir And Broad-leaved Trees Mixed Forests In The Over-logged Forest Region Of Changbai Mountain

The management of spruce-fir and broad-leaved trees mixed forests in the over-logged forest region of Changbai Mountain concerns steady development of economy and society and safe ecology directly. But at home, the research on management theory and technology system of spruce-fir and broad-leaved trees mixed forests is still at test stage. The most existing results are separate studies, so it is difficult to guide management practice of spruce-fir and broad-leaved trees mixed forests in an all-round way. In the long-term management practice, because of lacking essential management theory and technology, the management of spruce-fir and broad-leaved trees mixed forests is extensive generally. As a result, the forest structure is destroyed gradually, and the function is degrading. In order to meet the historical transition of forestry's leading function from timber production to construction of ecological environment, and to meet the need of managing practice of spruce-fir and broad-leaved trees mixed forests during development of society and economy, it is required to study management mode for spruce-fir and broad-leaved trees mixed forests urgently.In order to resume and improve forest structure of spruce-fir and broad-leaved trees mixed forests, to raise management competence and whole benefit, this research put forward the management mode for spruce-fir and broad-leaved trees mixed forests which was on the basis of structure characteristic analysis of existing forests. The main research contents are zoning, investigation, management aim, objective structure and structural adjustment, etc. The management mode is going to have both theory value and realistic practical significance during managing spruce-fir and broad-leaved trees mixed forests as an ecosystem.This research deeply studied the management mode of spruce-fir and broad-leavedtrees mixed forests by many study methods, such as combining theory with practice, combining qualitative judgment with ration and model, combining investigation in field with scientific analysis and reasoning. The main research results are as follows:(1) Studied structure characteristics by tree structure, age structure, space structure, regeneration structure, growth and yield etc., and grasped structure information of objective forests to offer the basis of structural adjustment and management mode for spruce-fir and broad-leaved trees mixed forests.(2) Took the lead in proposing zoning system, zoning index, zoning method, investigation index system, investigation method and calculating method. Designed forest questionnaire to offer theoretical foundation and method for zoning and investigating in over-logged forests.(3) Proposed general management aim of research object, objective structure in second and tertiary levels and quantitive index system of objective structure to offer the basis of management mode construction of spruce-fir and broad-leaved trees mixed forests.(4) Drew visual "structure Fig. "of objective structure and existing forests by nine structure factors including total forest volume, total tree number, ratio of coniferous trees to broad-leaved tress, and tree number and volume of all diameter classes, which could not merely describe structure information of complicated forests simply and intuitively, and also compare existing forests structure with objective structure, and then get their differences to, so that offer intuitionistic basis of structural adjustment and management mode for spruce-fir and broad-leaved trees mixed forests.(5) For the first time put forward the method of controlling cutting trees with objective trees, definition of objective tree, structure of objective tree, and procedure of confirming objective tree to offer the basis of structural adjustment in spruce-fir and broad-leaved trees mixed forests.(6) Proposed scientific and quantitive management mode including zoning, investigation, management principles, management aim, objective structure, and management technology system of structural adjustment etc. to offer theoretical foundation...