摘要
西南桦不同密度6a的试验结果显示:西南桦属速生树种,人工林初期生长很快,树高生长(1 5年生)达1 22 1 90m,胸径生长(3 6年生)达1 12 2 91cm。密度对树高生长有影响但不显著,而与胸径生长呈显著负相关。最大和最小密度林分间平均胸径相差2 88cm,3m×3m林分比1 5m×2m林分林木生长量高32 3%,比2m×2m林分高28 4%,比2m×3m林分高11 6%;单株材积生长与密度亦呈负相关关系,其关系式可用V=ax-b来表示。而林分蓄积则与密度呈正相关关系,即密度大林分蓄积量高,反之则小。随林龄增长,不同密度林分间蓄积差异逐渐缩小。要培育中大径材的西南桦人工林,造林密度不宜大,可考虑采用2m×3m及3m×3m的株行距。
A spacing trial for Betula alnoides was established in Daqingshan, Guangxi. The results showed that spacing has no considerable impact on height growth while remarkably negative impact on diameter growth. The difference of mean DBH between 3 m×3 m and 1.5 m×2.0 m is 2.88 cm. The growth increment of tree with spacing 3 m × 3 m is 32.3% higher than that with the spacing 1.5 m×20 m, 28.4% of 2 m×2 m, and 11.6% of 2 m×3 m. The volume increment of single tree was negatively correlated to the planting spacing which followed the formula of V=ax-b. The stock volume was positively correlated to planting spacing. The stock volume of these four planting spacing tend to be of less difference with time going.
出处
《林业科学研究》
CSCD
北大核心
2003年第1期81-86,共6页
Forest Research
基金
九五"攻关项目(96 011 02 02 03)
关键词
西南桦
造林密度
林木生长
Betula alnoides
planting spacing
growth increment
