Department of Biology, Washington University in St. Louis, MO 63130, USA.
Am Nat. 2011 Apr;177(4):535-43. doi: 10.1086/658990.
Biotic homogenization, the loss of local biotic distinctiveness among locations (beta diversity), is a form of global change that can result from the widespread introduction of non-native species. Here, we model this process using only species' occupancy rates--the proportion of sites they occupy--without reference to their spatial arrangement. The nonspatial model unifies many empirical results and reliably explains >90% of the variance in species' effects on beta diversity. It also provides new intuitions and principles, including the conditions under which species' appearance, spread, or extirpation will homogenize or differentiate landscapes. Specifically, the addition or spread of exotic species that are more common than the native background rate (effective occupancy) homogenizes landscapes, while driving such species to extinction regionally or introducing rarer species differentiates them. Given the primacy of occupancy and our model's ability to explain its role, homogenization research can now focus on other factors.
生物同质化,即地点间本地生物独特性的丧失(β多样性),是一种全球性变化形式,可能源于非本地物种的广泛引入。在这里,我们仅使用物种的占有率(它们占据的站点比例)而不参考其空间排列来模拟此过程。非空间模型统一了许多经验结果,并可靠地解释了物种对β多样性影响的 >90%的方差。它还提供了新的直觉和原则,包括物种的出现、传播或灭绝将使景观同质化或差异化的条件。具体来说,比本地背景率(有效占有率)更常见的外来物种的添加或传播会使景观同质化,而使这些物种在区域灭绝或引入更稀有的物种则会使景观差异化。鉴于占有率的首要地位以及我们模型解释其作用的能力,同质化研究现在可以集中在其他因素上。