Stand Density Of Planted Scenic Forest Pinus Tabulaeformis And Platycladus Orientalis In Beijing Mountain Area

Plant scenic forest of density control in a rational manner, can effectively improve plant growth and stand structure, and help to improve forest productivity, forest scenic beauty and ecological benefits of forests. This paper takes typical Beijing artificial scenic forest mountain Platycladus orientalis and Pinus tabulaeformis as an example. Focus on the research of the structure and density of the stand, specific research results are as follows:(1) Planted mountain scenery of Beijing Platycladus orientalis and Pinus tabulaeformis, and the lateral distribution of the stand diameter structure. The results showed that the Platycladus orientalis and Pinus tabulaeformis comply with the Weibull distribution of the diameter distribution Platycladus orientalis follows the right side single-peak Mineyama shaped distribution, and Pinus tabulaeformis followed left side.(2) Using breast height and crown width respectively as two parameters to get the competition indexes study to study the relationship between species. The results showed that the competition index of both of them reflect the intraspecific competition of Platycladus orientalis and Pinus tabulaeformis increase when the diameter decreased Platycladus orientalis and Pinus tabulaeformis intraspecific competition are reflected in the increasing order as the diameter decreases; Intraspecific competition of Platycladus orientalis is stronger than interspecific competition. Breast height, intraspecific competition , interspecific competition and the overall competitiveness of the stand nearly followed power function. Breast height of subject plants negative correlated with the competition intensity. Most of competition index is above 0.3. Since Competition between tress is relatively strong, intermediate cutting can help to improve it.(3) Analysis of the spatial distribution pattern of Platycladus orientalis and Pinus tabulaeformis. Spatial distribution of Platycladus orientalis follows the uniform distribution. Pinus tabulaeformis, and Morus mongolica associated species are randomly distributed. Pinus tabulaeformis forest is aggregated distribution, Pinus tabulaeformis of interspecific competition is still fierce, and did not meet the relative stable communities' state.(4) Establishment the function between breast height, crown width and crown competition index such as Platycladus orientalis C_r=0.7D_1.3^0.6*(1-C_i) and Pinus tabulaeformis C_r=0.966D_1.3^{0.550*(1-C_i)} and thedensity managment table under different breast height, crown competition index. According to the average stand canopy, Platycladus orientalis, Pinus tabulaeformis theoretical density value and competition index are found in the density management table. It further proves that the Platycladus orientalis, Pinus tabulaeformis of the stand structure is not quite reasonable, competition among plants are strong. It is better to use intermediate cutting to control the plant density and improve beauty of landscape in Platycladus orientalis, Pinus tabulaeformis of planted mountain scenery of Beijing.