野牛通过破坏树树苗来改变黄石石北部的生态系统
Luke E Painter1, Robert L Beschta2, William J Ripple2
1Department of Fisheries, Wildlife, and Conservation Sciences Oregon State University Corvallis Oregon USA.
Ecology and evolution
|August 31, 2023
概括
美国野牛在黄石国家公园打破的树苗. 野牛种群的增加限制了树的恢复,使两种物种的保护目标复杂化.
科学领域:
- 生态生态学 生态生态学
- 保护生物学 保护生物学
- 野生动物管理 野生动物管理
背景情况:
- 大型食草动物对生态系统产生重大影响,但美国野牛 (Bison bison) 对震动的树 (Populus tremuloides) 的特定影响仍未得到充分研究.
- 洛基山 (Cervus canadensis) 种群的最近增加为黄石国家公园北部的树再生创造了机会.
- 了解草食动物的影响对于有效的生态系统管理和保护战略至关重要.
研究的目的:
- 调查和量化美国野牛对美国黄石国家公园北部的树幼苗生存的影响.
- 为了确定野牛在多大程度上破坏树茎并阻碍树恢复.
- 探索影响树幼苗损伤的生态因素,包括与鹿的相互作用.
主要方法:
- 在黄石国家公园北部87个树中实地采样青树苗.
- 使用本地和景观规模的采样图片来评估茎断裂.
- 采用直接观测,分析相对于食草动物密度 (野牛和鹿) 的破碎幼苗分布,并使用野牛便密度进行混合效应建模.
主要成果:
- 在北方地区,所有采样的树幼苗茎中,大约有18%显示出破裂的迹象.
- 证据强烈地将破坏归因于野牛,大部分损害发生在夏季高野牛和低鹿密度地区.
- 直接观测证实了野牛打破树茎,统计建模显示,野牛便密度和破碎树苗比例之间存在正相关性.
- 在受到严重影响的种群中,绝大多数幼苗被破坏,一些地区的幼苗数量比以前的调查减少.
结论:
- 黄石地区越来越多的美洲野牛种群正在积极破坏的树苗,从而抑制了正在进行的树恢复.
- 旨在保护野牛的保护工作无意中阻碍了树和其他木质物种的恢复,造成了保护冲突.
- 管理策略必须考虑野牛,鹿和植被之间的复杂相互作用,以实现公园中成功的长期生态恢复.
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