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对秃杉分布区13个县(市)的纯林、混交林、散生木、孤立木进行调查,选出236株作为初选优树,并观测这些候选优树的立地因子、生长性状等指标。经相关性分析,选择单株材积作为优树复选的主要指标。采用数量化回归的方法,建立经度、纬度、海拔、坡度、黑土层厚度、树龄6个数量因子和坡向、坡位、坡形、基岩、土壤类型、起源、立木类型7个定性因子与秃杉单株材积的回归方程,其复相关系数为0.799。秃杉单株材积实测值与理论值的差值(I_i)代表基因型值,其频率分布成正态分布。以I_i与差值平均值I±标准差δ相比较作为划分优树等级的依据,秃杉以候选优树70%的入选率统计。差值I_i≥I+0.3δ,即I_i≥1.644 6为Ⅰ级优树;I+0.3δ>I_i>I-0.3δ,即1.644 6>I_i>-1.644 6为Ⅱ级优树;I_i≤I-0.3δ,即I_i≤-1.644 6为Ⅲ级优树(一般林木),Ⅲ级优树淘汰不选。用此标准对秃杉236株野外初选优树进行复选,Ⅰ级优树54株,占候选优树的22.88%;Ⅱ级优树114株,占候选优树的48.31%;Ⅰ、Ⅱ级优树预估遗传增益达20.82%。
The survey was conducted on pure forests, mixed forests, scattered woods and isolated woods in 13 counties (cities) of Taiwania flousiana. A total of 236 primary trees were selected as primary trees and the site factors, growth traits index. After correlation analysis, single plant volume was selected as the main index of superior tree selection. Quantitative regression method was used to establish seven quantitative factors such as longitude, latitude, altitude, slope, thickness of black soil layer, age of 6, and seven qualitative factors such as aspect, slope position, slope shape, bedrock, soil type, The regression equation of Taiwania flousiana individual plant volume, the complex correlation coefficient of 0.799. The difference between actual measured value and theoretical value of Taiwania flousiana (I_i) represents the genotype value, and its frequency distribution is normal distribution. Based on I_i as the standard deviation δ of difference I ± standard deviation, Taiwania flousiana was selected according to 70% of elite candidate trees. Difference I_i≥I + 0.3δ, that is, I_i≥1.6446 is a grade I superior tree; I + 0.3δ> I_i> I-0.3δ, that is, 1.644 6> I_i> -1.644 6 is a grade II superior tree; I_i≤I -0.3δ, ie I_i≤-1.644 6 is grade Ⅲ superior tree (general tree), grade Ⅲ superior tree is eliminated. A total of 236 primary trees of Taiwania flousiana were selected by this standard. Fifty-four trees of grade I, accounting for 22.88% of the total, were selected as superior trees, 114 of which were Grade II, accounting for 48.31% The superior tree estimated the genetic gain of 20.82%.