Abstract Grasslands are the most threatened terrestrial ecosystem in the world, and as their extent declines so does the abundance of species that depend on them. Periodic resting of rangelands could be used to manipulate plant cover and create wildlife habitat, but its effects may vary with prior grazing intensity. Using a large-scale manipulative grazing experiment conducted from 2006 to 2014 in Grasslands National Park, Canada, we evaluated how the effects of rest on vegetation and songbird abundance varied based on previous cattle stocking rates. Our results indicate that in northern mixed-grass prairies, grazing-induced changes were reversible, even at high stocking rates applied for up to four years. Both vegetation and songbirds were resilient to grazing, generally returning to levels observed prior to livestock reintroduction in three or fewer years following removal of livestock. Songbirds with flexible habitat requirements, such as Passerculus sandwichensis and Ammodramus savannarum, responded more rapidly to livestock exclusion. Recovery of both plant and songbird species occurred more rapidly in lowlands than uplands. The retrogressive nature of succession in North American mixed-grass prairies offers managers an opportunity to take chances when attempting to create wildlife habitat with livestock grazing, as risk of irreversible change is relatively low under moderate climate conditions.

中文翻译：

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一个有弹性的系统：北美混合草草原对牲畜排斥反应迅速

摘要 草原是世界上受威胁最严重的陆地生态系统，随着其范围的减少，依赖于它们的物种的数量也在减少。牧场的周期性休整可用于操纵植物覆盖和创造野生动物栖息地，但其影响可能因先前的放牧强度而异。使用 2006 年至 2014 年在加拿大草原国家公园进行的大规模人工放牧实验，我们评估了休息对植被和鸣禽数量的影响如何根据以前的牛放养率而变化。我们的结果表明，在北部混牧草原，放牧引起的变化是可逆的，即使在长达四年的高放养率下也是如此。植被和鸣禽都适应放牧，通常在移除牲畜后的三年或更短的时间内恢复到重新引入牲畜之前观察到的水平。具有灵活栖息地要求的鸣禽，如 Passerculus三明治和 Ammodramus savannarum，对牲畜排斥反应更快。植物和鸣禽物种的恢复在低地比高地更快。北美混牧草原的退化性质为管理人员提供了一个机会，可以在尝试通过放牧来创造野生动物栖息地时抓住机会，因为在温和的气候条件下发生不可逆转变化的风险相对较低。植物和鸣禽物种的恢复在低地比高地更快。北美混牧草原的退化性质为管理人员提供了一个机会，可以在尝试通过放牧来创造野生动物栖息地时抓住机会，因为在温和的气候条件下发生不可逆转变化的风险相对较低。植物和鸣禽物种的恢复在低地比高地更快。北美混牧草原的退化性质为管理人员提供了一个机会，可以在尝试通过放牧来创造野生动物栖息地时抓住机会，因为在温和的气候条件下发生不可逆转变化的风险相对较低。