岩溶地区杉木容器苗分级方法及标准探讨

为筛选出适用于岩溶地区杉木容器苗分级的最佳方法,以岩溶地区1年生杉木容器苗为研究对象,运用相关分析、逐步聚类分析方法,进行苗木质量评价和分级标准的划分。结果表明:(1)生物量是影响杉木容器苗苗木质量的主要指标,而苗高、地径是其次要指标。(2)苗木质量分级(3级)结果显示,以逐步聚类方法分级,Ⅰ级苗苗高H≥25.80cm,地径D≥4.17mm;Ⅱ级苗苗高25.80cm>H≥21.6cm,地径4.17mm>D≥3.30mm;而以平均值±标准差的分级方法进行分级,1年生杉木容器苗分级标准为Ⅰ级苗苗高H≥27.44cm,地径D≥4.1mm;Ⅱ级苗苗高27.44cm>H≥22.67cm,地径4.1mm>D≥3.3mm。(3)平均值±标准差和逐步聚类两种分级方法所得结果相差不大,在生产中可选用计算方法相对简单的标准差法进行杉木的苗木分级。

Study on Grading Standard for One-Year-Old Container Seedling Quality of Phoebe zhennan

In order to improve the survival rate of planting seedlings of Phoebe zhen-nan, the grading standard for one-year-old container seedlings of Phoebe zhennan was developed by using cluster analysis. The results showed that the quality of Phoebe zhennan container seedlings could be estimated from seedling height and ground diameter. The Phoebe zhennan container seedlings were divided into 3 grades： Grade 1 （seedling height ≥ 38 cm; ground diameter ≥ 0.65 cm）, Grade 2 （31.7 cm ≤ seedling height 〈 38 cm; 0.56 cm ≤ ground diameter 〈 0.65 cm） and Grade 3 （seedling height 〈 31.7 cm; ground diameter 〈 0.56 cm）.