USDA-ARS Fort Keogh Livestock Range & Research Laboratory, Miles City, MT 59301, USA.
Ann Bot. 2012 Jul;110(2):213-22. doi: 10.1093/aob/mcs061. Epub 2012 Mar 25.
The study of soil biota in the context of exotic plant invasions has led to an explosion in our understanding of the ecological roles of many different groups of microbes that function in roots or at the root-soil interface. Part of this progress has been the emergence of two biogeographic patterns involving invasive plants and soil microbes. First, in their non-native ranges invasive plants commonly interact differently with the same soil microbes than native plants. Second, in their native ranges, plants that are invasive elsewhere commonly interact functionally with soil microbes differently in their home ranges than they do in their non-native ranges. These studies pose a challenge to a long-held paradigm about microbial biogeography - the idea that microbes are not limited by dispersal and are thus free from the basic taxonomic, biogeographical and evolutionary framework that characterizes all other life on Earth. As an analogy, the global distribution of animals that function as carnivores does not negate the fascinating evolutionary biogeographic patterns of carnivores. Other challenges to this notion come from new measurements of genetic differences among microbes across geographic boundaries, which also suggest that meaningful biogeographic patterns exist for microorganisms.
We expand this discussion of whether or not 'everything is everywhere' by using the inherently biogeographic context of plant invasions by reviewing the literature on interactions among invasive plants and the microorganisms in the rhizosphere. We find that these interactions can be delineated at multiple scales: from individual plants to continents. Thus the microbes that regulate major aspects of plant biology do not appear to be exempt from the fundamental evolutionary processes of geographical isolation and natural selection. At the important scales of taxonomy, ecotype and ecosystem functions, the fundamental ecology of invaders and soil microbes indicates that everything might not be everywhere.
在研究外来植物入侵时对土壤生物群的研究，使我们对许多在根系或根土界面发挥作用的不同微生物群体的生态作用有了爆炸式的了解。这一进展的一部分是出现了两种涉及入侵植物和土壤微生物的生物地理模式。首先，在非原生范围内，入侵植物与相同的土壤微生物的相互作用通常与本地植物不同。其次，在它们的原生范围内，在其他地方具有入侵性的植物在其原生范围内与土壤微生物的功能相互作用与在非原生范围内不同。这些研究对微生物生物地理学的一个长期存在的范式提出了挑战——微生物不受扩散的限制，因此不受构成地球上所有其他生命的分类学、生物地理学和进化框架的基本限制。作为类比，作为肉食动物的动物的全球分布并没有否定肉食动物令人着迷的进化生物地理模式。对这一概念的其他挑战来自于对微生物在地理边界上遗传差异的新测量，这也表明微生物存在有意义的生物地理模式。
我们通过回顾关于入侵植物与根际微生物相互作用的文献，在植物入侵的固有生物地理背景下扩展了关于“一切是否无处不在”的讨论。我们发现这些相互作用可以在多个尺度上进行划分：从单个植物到整个大陆。因此，调节植物生物学主要方面的微生物似乎不受地理隔离和自然选择等基本进化过程的影响。在分类学、生态型和生态系统功能等重要尺度上，入侵植物和土壤微生物的基本生态学表明，并非一切都无处不在。
