EFFECTS OF EXPERIMENTAL DEFOLIATION ON A POPULATION OF PEDUNCULATE OAK (QUERCUS-ROBUR L)
EFFECTS OF EXPERIMENTAL DEFOLIATION ON A POPULATION OF PEDUNCULATE OAK (QUERCUS-ROBUR L)
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DOI：
10.1111/j.1469-8137.1987.tb02930.x
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发表时间：
1987-11-01
期刊：
影响因子：
9.4
通讯作者：
WILLIS, AJ
中科院分区：
文献类型：
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作者：
HILTON, GM;PACKHAM, JR;WILLIS, AJ
在伍尔弗汉普顿[英国]的一个小区中，对196棵年轻的橡树进行了模拟落叶的三个严重程度的实验。与对照相比，去叶导致（1）生长突的产生提前（2）产生更多的小叶片;（3）主茎直径的减小值，可据此计算出生长速率，随去叶处理和生长条件的变化而变化，（4）木质部纤维比例较低的早材型木质部在整个生长季节形成。光脱叶，这些反应几乎不明显，但更严重的脱叶，形态学的影响占主导地位。最明显的影响，全落叶低生长率和木材解剖的影响。结果表明，大量的自然落叶可能会导致更新失败，虽然在无阴影的小区的幼树叶片损失的结果，而不是死亡的增长放缓。
An experiment simulating defoliation at three levels of severity was conducted on 196 young oaks in a plot at Wolverhampton [UK]. In comparison with control plants, defoliation caused (1) earlier production of growth spurts (which are normal in undefoliated trees) and formation of more lateral branches, which were susceptible to winter frost damage; (2) production of more abundant, smaller leaves; (3) reduced diameters of main stems, from which can be calculated growth rates, varying with both defoliation treatment and growing conditions over the year, and returning to normal vales as soon as defoliation ceased; (4) formation throughout the season of xylem of early wood type having a lower proportion of xylem fibres. With light defoliation, most of these responses were scarcely apparent, but with more severe defoliation, morphological effects dominated. The most noticeable effects of total defoliation were low growth rates and effects on wood anatomy. The results suggest that substantial natural defoliation could cause failure of regeneration, although in unshaded plots of young trees leaf loss results in retarded growth rather than death.