Studies On Spatial Distribution Patterns And Associations Of Typical Forest Ecosystems In Mount Tai

With the data collected from the permanent sampling plot with two areas of 0.96 hm2(160m*60m)and 0.6 hm2(100m*60m)on Mount Tai which was often studied,we studied the structural characteristics of main space community and the spatial patterns and spatial association at different growth stages were discussed based on Ripley's K-function.In the goal of optimizing the structure,we analyzed existing forest spatial structure characteristics,put forward the control index of the utility,and combined it with existing research results together.On formulating business objectives and reasonable technical measures to optimize the structure,we achieved at hfhf improving economic performance in this domain.The results showed that: mixed broadleaf-conifer forest arborous layer of high altitude area of Taishan Luo Han Cliff were investigated to be composed of 7 species,the most of them was Pinus tabulaeformis,which was regarded as the dominant species,the main companion species including Robinia pseudoacacia,Quercus acutissima,etc.The DBH distribution of P.tabulaeformis possessed one peak.During this study,the P.tabulaeformis population was randomly distributed except aggregated distribution at the small scale,and the aggregation strength of young trees was weak.Among the P.tabulaeformis population,the spatial relationship of small diameter class and big diameter class showed positive correlations,similarly,the spatial relationships of middle diameter class and big diameter class also showed positive correlations at small scales.At the other scales,they were uncorrelated.From the view of succession tendency,the forest ecosystem was relatively stable for the time being.The results of spatial relationship between P.Tabulaeformis and Q.variabilis indicated that small diameter class and middle diameter class of P.Tabulaeformis were uncorrelated with Q.variabilis population at the whole scale,and they were negative correlated on small scale.While the spatial relationship of big diameter class of P.Tabulaeformis and Q.variabilis population showed negative correlations at the whole scale significantly uncorrelated in small scale.The interspecific relationship of coniferous and broad-leaved mixed forest was mainly influenced by the big diameter individuals of Pinus tabulaeformis,and the dominance degree of Pinus tabulaeformis is obvious.Mixed broadleaf-conifer forest arborous layer of low altitude area of Taishan Luo Han Cliff were investigated to be composed of 6 species,the most information of them was Platycladus orientalis,which was regarded as the dominant species,the main companion species including Robinia pseudoacacia,Quercus acutissima,etc.The population of Platycladus orientalis was randomly distributed and clustered on a small scale,which was similar to that of the former Platycladus orientalis regeneration population as the sampling scale became larger and the aggregation degree showed a trend of diffusion.The Platycladus orientalis population was positively related to small trees,middle trees and small trees,and promoted each other,while the rest of them were independent of each other in space.Platycladus orientalis coniferous forest plots in interspecific relationship results:Taishan forest of Platycladus orientalis trees and tree species,Quercus acutissima and Platycladus orientalis population in the study on the overall spatial scale was significantly irrelated,and negatively correlated in small scale;The big diameter class of Q.acutissima population and Platycladus orientalis tree populations were significantly negative correlation on the whole scale,small scale was not related.The relationship between species of Platycladus orientalis coniferous forest is mainly affected by the large size of individual oak.The coniferous and broad-leaved mixed forest in Taishan forest ecosystem had been lost to the structure and function of the original forest because of the varying degree of human intervention.Lack of update in forest,the principal species had the tendency to larger disaster.The distribution of various tree species in Taishan forest ecosystem in space was mainly affected by the spatial distribution of big trees,the main reason was the large diameter trees with high canopy density,which was not conducive to the formation of small diameter trees growth under the forest environment,and developped a strong and competitive relationship.Therefore,the practice of management of forest ecosystems in Taishan in the future,the thinning measures such as adjusting the stand structure and regeneration seedling could be adopted,and combined with improving forest quality,promoting forest succession and sustainable development.