Wind Resistance Research Of Eucalyptus

Eucalyptus belongs to the family of Myrtaceae, is an excellent variety of cost-effective economic tree species. The concentrated expression of advantages including:The growth of wood extremely fast; The rotation time is very short; Tending and planting technology through decades of development has been very mature, could be applied to centralized management and high yield cultivation cultivation methods; Little harm by pests to Eucalyptus. Since 1980 the introduction of Eucalyptus, Eucalyptus plantings growth fast. The main provinces of planting Eucalyptus including:Guangdong, Guangxi, Yunnan, Fujian, Zhejiang, Jiangxi, Guizhou, Chongqing, etc. The main species of Eucalyptus plantation including: Eucalyptus urophylla, Eucalyptus grandis Hill ex Maiden, Eucalyptus globulus Labill., Eucalyptus camaldulensis Dehnh., EuCahetus dunnii Maiden, Eucalyptus, saligna Sm., etc. So far, Eucalyptus wood annual output has reached about 5 million hm3. Typhoon is a natural disaster of high global occurrence frequency, wide affect range, causing serious damage. Leizhou Peninsula is located in the southernmost tip of the continent, there will be an annual average of 2 to 3 typhoon, are typhoon-prone areas. Therefore, Leizhou Peninsula wind resistance mainly Eucalyptus trees and Eucalyptus screening various traits in wind resistance traits to their most relevant, is an important measure to foster wind varieties of Eucalyptus plantations on the healthy development of an important scientific and practical significance.Through the survey about tree height, DBH, cross sectional area, volume, quality, basic density, all dry density, In, 1w, lww, w, 1n/w, dynamic elastic modulus of the Leizhou Peninsula four major fast-growing and wind-resistance Eucalyptus trees(Eucalyptus camaldulensis Dehnh., Eucalyptus urophylla×E.grandis, L-9, M-11), and an analysis of the different species of Eucalyptus standing state of the forces, systematic analysis of the key traits affect performance Eucalyptus wind resistance. The main contents and results are as follows:1. Through wood grown survey and analytical analysis of the four species of Eucalyptus, between DBH, cross sectional area, volume, quality, basic density, all dry density, In, 1w, lww, w, 1n/w, dynamic elastic modulus and tree height was significantly correlated. Establish a fitting equation between the index and the tree height.2. By performing stretching trees experiment, get stretching trees fitting equation of four kinds of Eucalyptus tree species:Y=ax1+bx2+cx3+d, wherein Y represents force(Unit:N), x1 represents elastic(Unit:cm), x2 represents inclinometer measured vertically standing trees and pull direction perpendicular to the tilt angle(Unit: °), X3 represents trees tilt angle(Unit: °). Where L-9 and M-11’s decision coefficients of fitting equation were above 0.9, and significantly. Software analysis found negative correlation between no load and load standing shear force, standing tilt stress and tree height, found positive correlation between no load and load standing moment and tree height.3. Mutual authentication by enter regression analysis, backward regression analysis and canonical correlation analysis to obtain:the longer the In, the lighter standing, standing more bending; the bigger the standing, the longer the 1, standing more lodging; Description In play a key role in the role of standing in the wind.