华榛1年生实生苗质量分级标准的研究

Classification Standard for One Year's Old Seedling of Coryllus sinensis

以28个1 m×1 m的华榛1年生实生苗样方、1 924株苗木为研究对象,以地径、苗高为苗木质量分级指标,采用K-均值聚类分析法及4种标准差法,划分了华榛1年生实生苗分级临界值,经分析比较,以K-均值聚类分析法划分并整化的数据作为华榛1年生实生苗分级标准,其中Ⅰ级苗地径≥0.9 cm、苗高≥110 cm,Ⅱ级苗地径0.6~0.9 cm、苗高70~110 cm,Ⅲ级苗地径<0.6 cm、苗高<70 cm;华榛Ⅰ、Ⅱ级苗占比63.5%。

Based on 28 sample plots with 1 m ×1 m per plot of 1 year＇s old Corylus chinensis Franch,totally 1 924 individuals,classified seedlings as different classes accorded to quality judged with ground diameter（GD）and height of seedling. Used the K-average value clustering method and standard deviation method,analizing with integrating data, critical values for classification of 1 year＇s old seedlings had been determined as fellows,the standard for Ⅰ class seedling is GD ≥0.9 cm and seedling height ≥110 cm,for Ⅱ class seedling is 0.6～0.9 cm for GD,and 70～110 cm for seedling height,for Ⅲ class seedling is GD0.6 cm and seedling height70 cm. The survey results showed that propotion of Ⅰ and Ⅱ classes of Corylus chinensis seedlings is 63.5%.