Natural Dieback in Forests
Natural Dieback in Forests
复制标题
森林中的自然枯死
DOI：
10.2307/1310668
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发表时间：
1987
期刊：
影响因子：
10.1
通讯作者：
D. Mueller‐Dombois
中科院分区：
文献类型：
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作者：
D. Mueller‐Dombois
目前，许多公众关注和研究工作集中在工业国家的森林枯死。与空气污染有关的因素，如酸雨、氧化亚氮、臭氧水平的变化和重金属沉积，通常被认为是造成大西洋两岸树木死亡的原因。虽然很明显，来自附近冶炼厂的空气污染可以通过毒性导致林分树木死亡（Smith 1981），但酸雨与森林枯死的关系（Ulrich 1981, 1982）仍然是高度推测的（Cramer 1984, Johnson 1983, Kandler 1983, Nihlgard 1985, Rehfuess 1983, Schiitt and Cowling 1985）。这篇文章并不是为了减少人们对空气污染与森林枯死的关系的关注。相反，我们的目标是指出，林分水平的枯死决不是一种新现象，而且在许多情况下，这是自然原因造成的。虽然有时可以区分人为原因和自然原因的标准枯死，但通常很难确定确切的原因。枯死是邻近树木群体的死亡，而不是孤立的树木在绿色森林基质中死亡。枯枝林分是冠层损失严重的林分。在这些林分中，大多数树木不是死了，就是活力下降了。枯死这个词是
urrently, much public concern and research effort focuses on forest dieback in industrial countries. Factors associated with air pollution, such as acid rain, nitrous oxide, changes in the ozone level, and heavy metal deposition are often considered responsible for tree mortality on both sides of the Atlantic. While it is absolutely clear that air pollution from nearby smelters can cause stand-level tree mortality by toxification (Smith 1981), the acid-rain relationship with forest dieback (Ulrich 1981, 1982) is as yet highly conjectural (Cramer 1984, Johnson 1983, Kandler 1983, Nihlgard 1985, Rehfuess 1983, Schiitt and Cowling 1985). This article is not intended to diminish concern about air pollution's relationship to forest dieback. The objective instead is to point out that stand-level dieback in forests is by no means a new phenomenon and further that, in many cases, it is due to natural causes. While it is sometimes possible to distinguish between manmade and natural causes of standlevel dieback, it is usually difficult to determine the exact causes. Dieback is the death of groups of neighboring trees rather than isolated trees dying in an otherwise green forest matrix. Dieback stands are forest segments having significant loss of canopy. In these stands the majority of trees are either dead or display reduced vigor. The term dieback is