Native granivores reduce the establishment of native grasses but not invasive Bromus tectorum
Native granivores reduce the establishment of native grasses but not invasive Bromus tectorum
复制标题
本地食谷动物减少了本地草类的生长，但没有减少入侵的无芒雀麦
DOI：
10.1007/s10530-018-1789-x
复制
发表时间：
2018
影响因子：
2.9
通讯作者：
R. Callaway
中科院分区：
文献类型：
--
作者：
Jacob E. Lucero;R. Callaway
种子捕食可以通过对某些物种施加强有力的种群控制来构建植物群落，而对其他物种则没有。在这种情况下，来自各种生态系统的研究报告说，本地granivores选择性地从本地物种的种子，而不是外来入侵者的种子，这可能不成比例地有利于入侵者的建立，并促进他们在社区中的统治地位。然而，很少有研究连接本地种子的选择性觅食，建立本地和入侵物种之间的差异模式。因此，在何种程度上优先觅食本地种子有利于建立入侵植物是不清楚的。在这里，我们在分布在大盆地沙漠180，000平方公里的五个田间试验点使用了实验性种子添加和围封处理，比较啮齿动物觅食对建立不太喜欢的猫草的影响（雀麦-一种原产于欧亚大陆的一年生物种，在大盆地具有异国情调和高度入侵性）和四种更受欢迎的原生草，发生在cheatgrass。啮齿类动物觅食减少了至少80%的建立每个本地物种，但没有建立的cheatgrass的影响，这一发现是一致的研究地点。我们的研究结果表明，选择性觅食的本地物种可能有利于建立本地草cheatgrass，可能会加剧在北美最广泛的植物入侵之一。
Seed predation can structure plant communities by imposing strong population controls on some species but not others. In this context, studies from various ecosystems report that native granivores selectively forage for seeds from native species over seeds from exotic invaders, which could disproportionately favor the establishment of invaders and facilitate their dominance in communities. However, few studies have connected selective foraging for native seeds to differential patterns of establishment among native and invasive species. Thus, the extent to which preferential foraging for native seeds favors the establishment of invasive plants is unclear. Here, we used experimental seed additions and exclosure treatments at five field sites distributed across ≈ 80,000 km2 of the Great Basin Desert, USA to compare the effects of rodent foraging on the establishment of less-preferred cheatgrass (Bromus tectorum—an annual species native to Eurasia that is exotic and highly invasive across the Great Basin) and four species of more-preferred native grasses that commonly co-occur with cheatgrass. Rodent foraging reduced the establishment of each native species by at least 80% but had no effect on the establishment of cheatgrass, and this finding was consistent across study sites. Our results suggest that selective foraging for native species may favor the establishment of cheatgrass over native grasses, potentially exacerbating one of the most extensive plant invasions in North America.