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作 者:郭跃东[1]
出 处:《山西林业科技》2009年第2期6-9,共4页Shanxi Forestry Science and Technology
基 金:山西省留学基金项目(2008079);国家自然科学基金项目(30470316)
摘 要:以关帝山林区的天然华北落叶松为研究对象,在不同立地条件下设置了3块标准样地,选取25株平均标准木进行树干解析,采用Log istic方程和R ichards方程拟合树高和胸径、材积生长过程。结果表明:1)胸径、树高前5 a生长缓慢,5 a后加速生长,而材积在前10 a生长缓慢,10 a后加速生长。2)不同立地条件下华北落叶松胸径、树高、材积总生长量前30 a差别不明显,30 a后立地条件越好,三者的总生长量越大且长势较好,表现出速生丰产的优势。Taking natural Larix principis-rupprechtii in different stands in Guandi mounatain as the research objects, 25 average standard trees from 3 sample plots in different site condition were picked, the growth process of tree height, DBH, and volume were analyzed and simulated by the equation of Logistic equation and Richards equation. The result showed: tree height, DBH, and volume of Larix principis-rupprechtii showed siginificant difference in different site condition in 30 years, tree height and DBH grows slowly during the first 5 years, then began to speed up during the next 5 years; While volume grows slowly during the first 10 years, then began to speed up during the next 10 years ; During the first 30 years, the total growth of trees in different site condition has the nonsiginificant difference, while during the next 30 years, the better the stand condition, the stronger growth vigor and more growth mass in tree height, DBH, volume the trees show.
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