Study On The Spatial Structure Of Korean Pine Broad-leaved Forest In Huadian Area

The Korean pine broad-leaved mixed forest is the most important forest ecosystem type as the climax community in the temperate zone of China,not only in ecosystem service function but also in wood industry production.Because of the unreasonable management measures and the interference of human activities for a long time,the original Korean pine broad-leaved mixed forest has been lost,and the secondary forest was also affected by cutting and artificial destruction,which made the stand composition and spatial structure of the forest in an irrational successional direction.With the implementation of "Natural Forest Protection Project" in China,almost all of the forestry production departments(Forestry Bureau)in Changbai Mountain area gradually reduce or stop the forest cutting,to restore the Korean pine broad-leaved mixed forest.Accordingly,it is an urgent task for us to adjust the forest structure to improve the forest management of Korean pine broad-leaved mixed forest in this areaWe have set up four plots inside and outside Hongshi National Forest Park at Huadian City,Jilin Province,and used forest stand spatial structure parameters of uniform angle index,mingling,dominance to study the spatial structure based on our investigation.Through the three parameters of univariate analysis and bivariate distribution analysis,we got the result:The forest stands in this area was typical Korean pine broad-leaved mixed forest,but there are some differences in the composition of tree species in different regions.On the single index,as for the mingling,it was relatively high in different tree species and the average value were 0.81,0.77,0.81,0.76,and the distribution of the mingling of these plots from 0 to 1 had obvious upward trend;in the while there have a great different about dominance,Pinus koraiensis and Abies holophylla growth advantage at sample A,Juglans mandshurica and Fraxinus mandshurica growth advantage at sample B,Korean pine are occupied the dominant at samples C and D,in addition Acer Linn.was in the state of the doctrine or growth of compressive in four samples.For the uniform angle index,about 59%of trees showed random distribution,followed by regularity distribution and irregularity distribution,respectively were 20%and 16%.In the whole,the values from 0 to 1 presented normal distribution.For double index analysis,in the mingling-dominance bivariate distribution,types of M=1,U=0 were dominant,and the values of mingling from 1 to 0 there were a decrease in the overall trend when the values of dominance were fixed;in mingling-uniform angle index bivariate distribution,the values of mingling from 1 to 0 there were decrease in the overall when the values of uniform angle index were fixed,the values of uniform angle index from 0.5 to 1 and 0 sides also appeared a downward trend,and similar to normal distribution when the values of mingling were fixed;in the bivariate distribution of uniform angle index-dominance,with tree distribution pattern from the values of uniform angle index varies from the intermediate type to the two ends,the frequency of the same dominance decreased gradually,but the frequency of dominance with the same distribution pattern had no obvious change with the values of dominance increasing when uniform angle index is fixedBased on the results,we combined single index analysis and bivariate distribution analysis of spatial structure parameters,to provide feasible methods for optimal stand structure,and new ideas for the study of forest spatial structure and management of forest ecosystem,finally,provide scientific basis for the protection and restoration of Korean pine broad-leaved mixed forest.