Study On The Spatial Distribution Patterns And Regeneration Of Main Forest Types In Over-cutting Forest Area In Changbai Mountains

The research objects are the main forest types in Jingouling Forest Farm, Wangqing Forest Bureau, Jilin province, which are near primitive mixed stand of coniferous and broad-leaved trees, Broad-leaved Korean Pine over-cutting forest and artificial and natural larch mixed stand. The author studied stand structure, importance value of tree species, survival curve of tree species, spatial pattern of arbors, quantity characteristic of regeneration seedlings, distribution pattern of seedlings and the function of dead woods for natural forest regeneration in order to find the close to nature management approach for different forest types in over-cutting forest area.The research results were as follows:1. The spatial distribution patterns of arbors both in near primitive mixed stand of coniferous and broad-leaved trees and in artificial and natural larch mixed stand were random distribution. The spatial distribution pattern of arbors in Broad-leaved Korean Pine over-cutting forest was near to random distribution. All of the spatial patterns of seedlings in the three forest types were clump distributions.2. The numbers of regeneration seedlings descended with ascending height in near primitive mixed stand of coniferous and broad-leaved trees and in Broad-leaved Korean Pine over-cutting forest. But the number of seedlings increased with ascending height in artificial and natural larch mixed stand.3. The volume of dead woods in near primitive mixed stand of coniferous and broad-leaved trees was 241.7 m³?hm^-2, which accounted for 44.05 percent of total forest volume. The volume of dead woods in Broad-leaved Korean Pine over-cutting forest was 66.9 m³ ? hm^-2 ,which accounted for 31.78 percent of total forest volume. The former was near to 4 times of the latter.There was no dead woods in artificial and natural larch mixed stand. The diameter at bigger end in near primitive mixed stand of coniferous and broad-leaved trees was distributed rather equably, which belongs to 46 to 54 cm diameter grade was a little more. There were dead woods only in 14,22,42,54,70 cm diameter grade in Broad-leaved Korean Pine over-cutting forest.4. The distribution of regeneration seedlings on dead woods took on a normal distribution. Most regeneration seedlings located at central section of a dead wood, and concentrated in less than 30cm height range. The average numbers of regeneration seedlings on dead woods in near primitive mixed stand of coniferous and broad-leaved trees and in Broad-leaved Korean Pine over-cutting forest were 3.18 and 4.10 every hectare respectively, which were quite higher than that in woodland.