Biodiversity as a barrier to ecological invasion
Biodiversity as a barrier to ecological invasion
复制标题
DOI：
10.1038/nature00776
复制
发表时间：
2002-06-06
期刊：
影响因子：
64.8
通讯作者：
Reich, P
中科院分区：
文献类型：
--
作者：
Kennedy, TA;Naeem, S;Reich, P
生物入侵是一个普遍存在且代价高昂的环境问题(1,2)，在过去的半个世纪中一直是密集管理和研究活动的焦点。然而，对社区对入侵的易感性的准确预测仍然难以实现。多样性抵抗假说认为，多样化的群落具有高度竞争性并且容易抵抗入侵(3-5)，该假说得到了在小空间尺度上进行的理论(6)和实验研究(7-14)的支持。然而，也有令人信服的证据表明，在区域尺度上测量时，本地物种和入侵物种的多样性之间存在正相关关系(3,11,15,16)。尽管后一种关系可能是由外在因素引起的，例如资源异质性，它与大范围内的本地物种和入侵物种的多样性共同变化，但在局部范围内赋予不同群落更大的入侵抵抗力的机制仍然未知。使用邻域分析（植物竞争研究中的一种技术）（17-19），我们在此表明，小型实验草地中的物种多样性通过增加局部植物邻域的拥挤度和物种丰富度来增强入侵抵抗力。入侵植物的建立（入侵者数量）和成功率（大型入侵者的比例）都会减少。这些结果表明，当地的生物多样性是抵御入侵者蔓延的重要防线。
Biological invasions are a pervasive and costly environmental problem(1,2) that has been the focus of intense management and research activities over the past half century. Yet accurate predictions of community susceptibility to invasion remain elusive. The diversity resistance hypothesis, which argues that diverse communities are highly competitive and readily resist invasion(3-5), is supported by both theory(6) and experimental studies(7-14) conducted at small spatial scales. However, there is also convincing evidence that the relationship between the diversity of native and invading species is positive when measured at regional scales(3,11,15,16). Although this latter relationship may arise from extrinsic factors, such as resource heterogeneity, that covary with diversity of native and invading species at large scales, the mechanisms conferring greater invasion resistance to diverse communities at local scales remain unknown. Using neighbourhood analyses, a technique from plant competition studies(17-19), we show here that species diversity in small experimental grassland plots enhances invasion resistance by increasing crowding and species richness in localized plant neighbourhoods. Both the establishment (number of invaders) and success (proportion of invaders that are large) of invading plants are reduced. These results suggest that local biodiversity represents an important line of defence against the spread of invaders.