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毛竹枝下高和胸径影响因素研究

Effects of the Factors on under Brach Height and DBH of Phyllostachys Pubescens Mazel

【作者】 孙鸿宇

【导师】 宋丁全; 王福升;

【作者基本信息】 南京林业大学 , 生态学, 2010, 硕士

【摘要】 毛竹原产于中国,是一种经营周期短,经济效益高,生态效益好,地域分布广的优良树种,也是中国竹类中经济价值最大的竹种。本文通过对江苏省宜兴地区50块毛竹标准地进行群落调查,从竹林生态学的角度,运用EXCEL、SPSS、MATLAB等软件,分析了坡度(X1)、坡向(X2)、坡位(X3)、腐殖质层厚度(X4)、郁闭度(X5)、立竹度(X6)6个因子分别对毛竹枝下高、胸径生长量的影响,以及建立枝下高和胸径间的数学模型。研究结果表明:(1)对6个环境因子进行了偏相关分析和逐步回归分析,结果显示在宜兴地区不同环境条件对毛竹枝下高生长量影响大小顺序是:郁闭度(X5)、坡位(X3)和立竹度(X6),并得到模型回归方程为:Y1=2.293+0.412X3+2.987X5-4.294X6。(2)对6个环境因子进行了偏相关分析和逐步回归分析,结果显示在宜兴地区不同环境条件对毛竹胸径影响大小顺序是:郁闭度(X5)、立竹度(X6)和坡位(X3),并得到模型回归方程为:Y2=6.937+0.555X3+ 5.528X5-10.188X6。(3)通过偏相关分析发现,在立竹度固定的毛竹林样地中,影响郁闭度的主要因子是坡向。(4)对6个环境因子进行因子分析,将6个变量转换成3个主成分,其累计贡献率达到86.1%。第一主成分可被看作是反应郁闭度的因子;第二主成分可被看作是反应坡位和腐殖质层厚度的因子;第三主成分可被看作是反应立竹度的因子。(5)建立了毛竹林枝下高(Y1)和胸径(X)间的数学模型:Y1=-0.744+0.542X复相关系数R=0.949,其达到了极显著水平,有统计学意义。

【Abstract】 Phyllostachys pubescens Maze Originated in China,it generally distributes in China, it is a major economic bamboo species. From the view of Bamboo Forest Ecology, based on the Software of EXCEL, SPSS and MATLAB, and surveying data of the fifty sample plots of Phyllostachys pubescens Mazel in Yixing district of Jiangsu province, the effects of gradient (X1), aspect (X2), slope position(X3), humus thickness(X4), canopy density (X5)and density(X6) on the increment of Phyllostachys pubescens Mazel were analyzed,and setting up under brach height and DBH’s mathematical model.The results show that:(1) We used the six site factors to make partial correlation analysis and stepwise regression analysis, the result showed the canopy density (X5), slope position(X3) and density(X6) were the main factors on growing of under brach height The mathematical model: Y1=2.293+0.412X3+2.987X5-4.294X6(2) We used the six site factors to make partial correlation analysis and stepwise regression analysis, the result showed the canopy density(X5), density(X6) and slope position(X3) were the main factors on growing of DBH. The mathematical model: Y2=6.937+0.555X3+ 5.528X5-10.188X6(3) If the same density of Phyllostachys pubescens Maze, aspect is the main factor on canopy density.(4) Then taking the six site factors principal analysis, make the six variables turn to three principal components, and this three components’cumulative proportion got to 86.1%.(5) Setting up under brach height (Y1) and DBH’s(X) mathematical model: Y1=-0.744+0.542X, Multiple correlation coefficient R=0.949,it Reached a significant level.

  • 【分类号】S795
  • 【下载频次】174
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