当前位置: X-MOL 学术Forest Ecol. Manag. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
The effect of water availability on growth strain in Eucalyptus grandis-urophylla trees
Forest Ecology and Management ( IF 3.7 ) Pub Date : 2021-01-16 , DOI: 10.1016/j.foreco.2021.118926
Z. Naghizadeh , C.B. Wessels

The Eucalyptus genus is the most widely planted hardwood worldwide. It is, however, mostly used for low value products as a result of various wood quality problems. Splitting and distortion of wood due to growth stresses is arguably the most critical quality issue for this genus. In this research, the effect of water availability on the peripheral and internal longitudinal growth strain of 7-year-old Eucalyptus grandis-urophylla trees was investigated. A new method using a custom modified digital dial gauge was developed for measuring the internal growth strain variability in standing trees – the first such method according to the best of our knowledge. Growth strain was measured on three sites with different water availability. The results showed that not only peripheral but also internal longitudinal growth strain was significantly affected by the water availability. Trees from the wet site showed higher surface and internal growth strain, while the trees planted on the dry site indicated lower and more uniform growth strain distribution inside their stems. Apart from the water availability, the direction of the prevailing wind was found as another influencing factor on growth strain. Both the radial and longitudinal patterns of longitudinal growth strains were determined and the results showed that growth strain decreased with height and that the neutral points of strain for all sites were between 8 and 9 tenths of the diameter from the pith. Growth strain was also measured destructively on logs and it was found that there was a significant difference between the growth strains of the logs from the same height but from different sites. The results also showed that, on the same log, the end split length per area of log cross section occurring during cross cutting could be modelled moderately well with a linear regression equation (R2 = 0.67). The model included the variables maximum compressive strain over the radius, the maximum difference of compressive and tensile strain (between south and east directions) and the sum of strain difference over the radius between adjacent points divided by the diameter.



中文翻译:

的水供应上生长应变的影响巨桉-尾叶桉

桉树属是最广泛种植的硬木全球。但是,由于各种木材质量问题,它通常用于低价产品。由于生长压力引起的木材劈裂和变形可能是该属最关键的质量问题。在这项研究中,水分供应对7岁大桉树-尾叶桉外围和内部纵向生长株的影响对树木进行了调查。开发了一种使用定制的改进型数字千分表的新方法,用于测量立木中的内部生长应变变异性,这是根据我们所学知识中的第一种。在三个可用水量不同的地点测量了生长应变。结果表明,不仅可用水量显着影响外围,而且内部纵向生长应变也受到显着影响。来自湿地的树木显示出较高的表面和内部生长株,而种植于干燥地的树木表明其茎内部的生长株分布较低且更均匀。除了水的可利用性之外,盛行风的方向还被认为是另一个影响生长应变的因素。确定了纵向生长应变的径向和纵向模式,结果表明生长应变随高度降低,并且所有位点的应变中性点都在距离髓长的直径的八十分之一到九十分之一之间。还用破坏性的方法在原木上测量了生长应变,发现在相同高度但不同位置的原木生长应变之间存在显着差异。结果还表明,在同一条测井曲线上,可以使用线性回归方程(R 还用破坏性的方法在原木上测量了生长应变,发现在相同高度但不同位置的原木生长应变之间存在显着差异。结果还表明,在同一条测井曲线上,可以使用线性回归方程(R 还用破坏性的方法在原木上测量了生长应变,发现在相同高度但不同位置的原木生长应变之间存在显着差异。结果还表明,在同一条测井曲线上,可以使用线性回归方程(R2  = 0.67)。该模型包括变量在半径上的最大压缩应变,压缩应变和拉伸应变的最大差(南北和东向之间)以及相邻点之间的半径上的应变差之和除以直径。

更新日期:2021-01-18
down
wechat
bug