Cattle affect early post-fire regeneration in a Nothofagus dombeyi-Austrocedrus chilensis mixed forest in northern Patagonia, Argentina
Cattle affect early post-fire regeneration in a Nothofagus dombeyi-Austrocedrus chilensis mixed forest in northern Patagonia, Argentina
复制标题
DOI：
10.1016/j.biocon.2008.06.016
复制
发表时间：
2008-09-01
影响因子：
5.9
通讯作者：
Veblen, Thomas T.
中科院分区：
文献类型：
--
作者：
Blackhall, Melisa;Raffaele, Estela;Veblen, Thomas T.
在森林生态系统中，严重火灾一直是塑造生态系统结构的重要过程，了解引进牲畜对火灾后植被恢复的影响对于有效的森林资源管理和保护至关重要。在巴塔哥尼亚西北部的纳韦尔瓦皮国家公园，我们研究了牲畜对 1999 年被烧毁的东柏-南方松森林火灾后恢复的影响。我们通过围栏试验排除了牛，并比较了围栏和未围栏对照地块在 5 年期间的植被特征。尽管牛没有显着降低植物总覆盖度或物种总丰富度，但它们确实降低了包括优势树种在内的木本物种的最大高度。 Chusquea culeou 是一种高大的林下竹子，会阻碍优势树种的建立和高度生长。尽管 Culeou 占牛饮食的最大比例，但其平均覆盖度和平均最大高度并没有受到牛的强烈影响。无围栏地区冬贝猪笼草和南柏树苗高度生长的减少表明，最近烧毁地区的牛群可能会导致火灾后从高大森林过渡到以竹子为主的灌木丛，而这种情况在该地区已经很普遍了。因此，这些结果为国家公园内最近被烧毁的南栎和南柏森林提供了足够长的围栏，以允许优势树种生长到不再受到牛群啃食的严重抑制的高度。 (C) 2008 Elsevier Ltd. 保留所有权利。
In forest ecosystems where infrequent, severe fires have been an important process in shaping ecosystem structure, understanding the effects of introduced livestock on post-fire recovery of the vegetation is essential for effective forest resource management and preservation. In Nahuel Huapi National Park in northwestern Patagonia, we studied the effects of livestock on the post-fire recovery of a Nothofagus dombeyi-Austrocedrus chilensis forest that was burned in 1999. We experimentally excluded cattle by fencing plots and compared the vegetation characteristics of fenced and unfenced control plots over a 5-year period. Although cattle did not significantly reduce total plant cover or total species richness, they did reduce maximum heights of woody species including the dominant tree species. Chusquea culeou, a tall understory bamboo, can impede establishment and height growth of the dominant tree species. Although C. culeou accounts for the largest percentage of cattle diet, its mean cover and mean maximum height were not strongly affected by cattle. The reduction in the height growth of seedlings of N. dombeyi and Austrocedrus in the unfenced areas implies that presence of cattle in the recently burned areas may contribute to a post-fire transition from tall forest to bamboo-dominated shrubland that is already widespread in this landscape. Thus, these results provide support for the fencing of recently burned Nothofagus and Austrocedrus forests in the national parks for periods long enough to allow the dominant tree species to grow to heights at which they are no longer severely inhibited by cattle browsing. (C) 2008 Elsevier Ltd. All rights reserved.