Impacts of solar ultraviolet-B radiation on terrestrial ecosystems of Tierra del Fuego (southern Argentina) -: An overview of recent progress
Impacts of solar ultraviolet-B radiation on terrestrial ecosystems of Tierra del Fuego (southern Argentina) -: An overview of recent progress
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DOI：
10.1016/s1011-1344(01)00152-x
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发表时间：
2001-09-01
影响因子：
5.4
通讯作者：
Scopel, AL
中科院分区：
文献类型：
--
作者：
Ballaré, CL;Rousseaux, MC;Scopel, AL
南美洲最南端的火地岛南部被密集的假山毛榉覆盖。森林和以泥炭藓为主的泥炭沼泽受到臭氧消耗和太阳紫外线-B辐射水平增加的影响。在过去的5年里，我们研究了太阳UV-B对该地区自然生态系统的一些生物影响。我们已经解决了两个一般性问题：（i）在南极臭氧“空洞”的影响下，UV-B水平的波动是否具有任何可测量的生物影响，以及（ii）太阳（环境）的长期影响是什么？对火地岛生态系统的紫外线-B？在本文中，我们提供了在该项目的前4年所取得的进展的概述。我们重点讨论了以下结果：（1）环境UV-B对该地区草本和禾本科植物的生长有轻微但显著的抑制作用（生长减少小于或等于12%），而在木本多年生植物中没有一致的抑制作用;（2）在研究得最详细的物种Gunnera magellanica中，太阳UV-B的抑制作用伴随着叶片组织中DNA损伤水平的增加，早春的DNA损伤密度与地面UV-B辐射剂量有明显的相关性：（3）草本植物对UV-B辐射的适应性反应很小，如防晒水平的提高和DNA修复能力的增强;（4）UV-B对异养生物有显著的影响，其中对昆虫植食性有显著的抑制作用。从本次审查中总结的实验结果清楚地表明，紫外线-B影响几个潜在的重要过程和生态相互作用在火地岛的陆地生态系统。(C)2001 Elsevier Science B. V.保留所有权利。
The southern part of Tierra del Fuego, in the southernmost tip of South America, is covered by dense Nothofagus spp. forests and Sphagnum-dominated peat bogs, which are subjected to the influence of ozone depletion and to increased levels of solar ultraviolet-B radiation (UV-B). Over the last 5 years we have studied some of the biological impacts of solar UV-B on natural ecosystems of this region. We have addressed two general problems: (i) do the fluctuations in UV-B levels under the influence of the Antarctic ozone 'hole' have any measurable biological impact, and (ii) what are the long-term effects of solar (ambient) UV-B on the Tierra del Fuego ecosystems? In this paper, we provide an overview of the progress made during the first 4 years of the project. We highlight and discuss the following results: (1) ambient UV-B has subtle but significant inhibitory effects on the growth of herbaceous and graminoid species of this region (growth reduction less than or equal to 12%) whereas no consistent inhibitory effects could be detected in woody perennials; (2) in the species investigated in greatest detail, Gunnera magellanica, the inhibitory effect of solar UV-B is accompanied by increased levels of DNA damage in leaf tissue, and the DNA damage density in the early spring is clearly correlated with the dose of weighted UV-B measured at ground level; (3) the herbaceous species investigated thus far show little or no acclimation responses to ambient UV-B such as increased sunscreen levels and DNA repair capacity; and (4) ambient UV-B has significant effects on heterotrophic organisms, included marked inhibitory effects on insect herbivory. The results from the experiments summarized in this review clearly indicate that UV-B influences several potentially important processes and ecological interactions in the terrestrial ecosystems of Tierra del Fuego. (C) 2001 Elsevier Science B.V. All rights reserved.