摘要
对徐淮平原农田防护林杨树生长特性的研究结果表明：①同一林带不同林木个体随着年龄的增长，树高、胸径和冠幅的绝对差异逐渐增大而相对差异逐渐减小。②林带建立２～３ａ后，林木进入速生期。③树高、胸径和材积生长符合Ｌｏｇｉｓｔｉｃ方程。④林网中不同杨树元性系生长速度从快到慢依次是：ＮＬ─１１６杨，ＮＬ─１２１杨，Ｗ─４６杨，ＮＬ－２０３杨，１─６９杨和Ｉ─２１４杨，基干林带中ＮＬ─１０５杨和ＮＬ─１０６杨生长优于林网中林木。⑤ＮＬ─２０３杨冠幅小，适于在农田防护林中推广。⑥林带方向上的冠幅一般小于与其垂直方向上的冠幅。⑦冠幅与胸径的相关性较高，与树高没有相关性。⑧树高与胸径有着密切关系。与片林相比，林网中的林木尖削度较大。
With the
growth of Populus trees,the absolute variations of their height,breast-heigbt diameter and
crown breadth of different individuals in the same belt gradually increased whereas the relative
variations gradually decreased.(2)After two or three years of planting,the forest entered its
rapid-growth period.(3)The growth of the height,breast-height diameter and volume could be fit
by the Logistic Curve.(4) The growth speed order(from fast to low)of different clones
was:NL-116,NL-121,W-46,NL-203=I-69,I-214.NL-105 and NL-106 in backbone forest belts had a
faster growth speed than those in protection forest network.(5)The crown breadth of NL-203 was
less than the others’,so it’s suitful for NL-203 to be widely planted on the side of
farmland.(6)Thecrown breadth in the direction of forest belts was less than that in its vertical
direction.(7)In the forest belts with the same age,crown breadth was closely related witb
breast-height diameter but not with height.(8)There was a close relationship between be ight
and breas-height diameter.Compared with populus trees in a tract of forests,those in the forest
belts were obviously tapered.
出处
《浙江林学院学报》
CSCD
1996年第3期280-285,共6页
Journal of Zhejiang Forestry College
基金
黄淮海综合开发技术研究项目
关键词
农田防护林
杨属
生长特性
树种
Populus,agricultural protection forests.growth
curves
tree height,breast-height diameters,canopy,Xuzhou
