On July 23rd2003,Leizhou Peninsula was attacked by typhoon "IMBUDO",when the author investigated the capacity of wind ressitance of 27 Eucalyptus clones and different aged stands of E.urophylla U6,and E.ABL ...On July 23rd2003,Leizhou Peninsula was attacked by typhoon "IMBUDO",when the author investigated the capacity of wind ressitance of 27 Eucalyptus clones and different aged stands of E.urophylla U6,and E.ABL 12 W5 clones.Several methods including comparison,variance analysis,and regression analysis,were used to analyze the relationship between growth period,stand densitiy,direction,and the characteristics of Eucalyptus clones and wind-resistance.The results showed that the wind-resistance of Eucalyptus clones was closely correlated with the age,density,and direction of the stand.The difference of clones in tree height,DBH increment and timber density led to the significantly difference in wind-resistance.The following Ecualytpus clones with strong wind-resistance were selected:MJ41,MJ53,MJ57,MJ43,MJ45,W5,EC1,W6,W2,and ZU6.展开更多
Based on the discussion of relationships between thinning and wind damage, and published information, a method for estimating risk ratios of wind damage was developed. Estimations of risk-ratio for Pinus thunbergii tr...Based on the discussion of relationships between thinning and wind damage, and published information, a method for estimating risk ratios of wind damage was developed. Estimations of risk-ratio for Pinus thunbergii trees and stands were de-duced from stem bending theory and coefficients characterizing wind profile, distribution of branches and optical stratification po-rosity. The results showed that if the value of constant b in the branch distribution-model equals the attenuation coefficient s in the wind profile model for a single tree crown, then the parameter H/D1.33 (height over stem diameter cubed) can be used to compare and evaluate the risk-ratio of wind damage for individual trees. The same method can be applied to stands using the coefficient of wind profile in a stand, i.e. attenuation coefficient , the coefficient from distributions of optical stratification porosity, i.e. extinction coefficient , and the parameter D1.33. The application of parameter H/D1.33 and the process of determining risk ra-tios of wind damage for stands were also given in the paper.展开更多
文摘On July 23rd2003,Leizhou Peninsula was attacked by typhoon "IMBUDO",when the author investigated the capacity of wind ressitance of 27 Eucalyptus clones and different aged stands of E.urophylla U6,and E.ABL 12 W5 clones.Several methods including comparison,variance analysis,and regression analysis,were used to analyze the relationship between growth period,stand densitiy,direction,and the characteristics of Eucalyptus clones and wind-resistance.The results showed that the wind-resistance of Eucalyptus clones was closely correlated with the age,density,and direction of the stand.The difference of clones in tree height,DBH increment and timber density led to the significantly difference in wind-resistance.The following Ecualytpus clones with strong wind-resistance were selected:MJ41,MJ53,MJ57,MJ43,MJ45,W5,EC1,W6,W2,and ZU6.
基金This study was supported by Innovation Research Project of Chinese Academy of Sciences and the Ministry of Culture and Education Japanese Government.
文摘Based on the discussion of relationships between thinning and wind damage, and published information, a method for estimating risk ratios of wind damage was developed. Estimations of risk-ratio for Pinus thunbergii trees and stands were de-duced from stem bending theory and coefficients characterizing wind profile, distribution of branches and optical stratification po-rosity. The results showed that if the value of constant b in the branch distribution-model equals the attenuation coefficient s in the wind profile model for a single tree crown, then the parameter H/D1.33 (height over stem diameter cubed) can be used to compare and evaluate the risk-ratio of wind damage for individual trees. The same method can be applied to stands using the coefficient of wind profile in a stand, i.e. attenuation coefficient , the coefficient from distributions of optical stratification porosity, i.e. extinction coefficient , and the parameter D1.33. The application of parameter H/D1.33 and the process of determining risk ra-tios of wind damage for stands were also given in the paper.
