Mechanical vulnerability and resistance to snapping and uprooting for Central Amazon tree species
Mechanical vulnerability and resistance to snapping and uprooting for Central Amazon tree species
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亚马逊中部树种的机械脆弱性以及抗折断和连根拔起的能力
DOI：
10.1016/j.foreco.2016.08.039
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发表时间：
2016
影响因子：
3.7
通讯作者：
N. Higuchi
中科院分区：
文献类型：
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作者：
G. H. P. M. Ribeiro;J. Chambers;C. Peterson;S. Trumbore;D. Marra;C. Wirth;J. Cannon;R. Negrón‐Juárez;A. Lima;E. Paula;J. Santos;N. Higuchi
对流风暴产生的高下降风是亚马逊地区树木死亡干扰事件的一个频繁和主要来源，影响到各种规模的森林结构和多样性，在盆地的西部和中部更经常观察到。亚马逊河中部的土壤质地也随着海拔沿着地形梯度的变化而变化很大，高原、斜坡和山谷的粘土含量分别减少。在这项研究中，我们调查了60棵树的临界转动力矩（Mcrit-旋转力在树的故障时刻，树的稳定性或抗风性的指标），范围从19.0到41.1厘米的直径在胸高（DBH）和位于不同的地形位置，并为不同的物种，使用电缆绞盘负荷传感器系统。我们的方法使用扭矩作为衡量树木折断或连根拔起的标准。这种方法可以更好地了解推翻热带森林树木所需的机械力，并为风抛扰动模型提供信息。在整个地形位置上，对cardeiro（Scleronema mincranthum（Ducke）Ducke），mata-matá（Sclerweileraspp.），以及从其他19个物种中随机挑选的树木。我们的分析表明，Mcrit失败的阻力增加的大小（胸径和ABG）和物种之间的差异。单独或合并的物种均未发现地形或失效模式的影响。对于随机种，总方差在Mcritexplained树的大小度量增加，从R2的0.49单独的胸径，0.68时，胸径和干鲜木材密度（SWD）包括在一个多元回归模型。这种机械的方法可以比较树木的脆弱性引起的风害跨生态系统，并促进使用森林结构信息的生态系统模型，包括可变电阻的树木死亡率诱导因素。我们的研究结果表明，观测到的地形差异，在风的脆弱性可能是由于海拔高度的风速差异，而不是由土壤相关的因素，可能影响Mcrit的差异。
High descending winds generated by convective storms are a frequent and a major source of tree mortality disturbance events in the Amazon, affecting forest structure and diversity across a variety of scales, and more frequently observed in western and central portions of the basin. Soil texture in the Central Amazon also varies significantly with elevation along a topographic gradient, with decreasing clay content on plateaus, slopes and valleys respectively. In this study we investigated the critical turning moments (Mcrit- rotational force at the moment of tree failure, an indicator of tree stability or wind resistance) of 60 trees, ranging from 19.0 to 41.1 cm in diameter at breast height (DBH) and located in different topographic positions, and for different species, using a cable-winch load-cell system. Our approach used torque as a measure of tree failure to the point of snapping or uprooting. This approach provides a better understanding of the mechanical forces required to topple trees in tropical forests, and will inform models of wind throw disturbance. Across the topographic positions, size controlled variation inMcritwas quantified for cardeiro (Scleronema mincranthum(Ducke) Ducke), mata-matá (Eschweileraspp.), and a random selection of trees from 19 other species. Our analysis ofMcritrevealed that tree resistance to failure increased with size (DBH and ABG) and differed among species. No effects of topography or failure mode were found for the species either separately or pooled. For the random species, total variance in Mcritexplained by tree size metrics increased from an R2of 0.49 for DBH alone, to 0.68 when both DBH and stem fresh wood density (SWD) were included in a multiple regression model. This mechanistic approach allows the comparison of tree vulnerability induced by wind damage across ecosystems, and facilitates the use of forest structural information in ecosystem models that include variable resistance of trees to mortality inducing factors. Our results indicate that observed topographic differences in windthrow vulnerability are likely due to elevational differences in wind velocities, rather than by differences in soil-related factors that might effectMcrit.
影响因子：
5.2
作者：
Iida, Yoshiko;Poorter, Lourens;Kohyama, Takashi S.
通讯作者：
Kohyama, Takashi S.
松岛英子：《命理学学报》第 9 期。
DOI：
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发表时间：
--
期刊：
影响因子：
--
作者：
通讯作者：
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影响因子：
56.9
作者：
ter Steege, Hans;Pitman, Nigel C. A.;Silman, Miles R.
通讯作者：
Silman, Miles R.