Species pool, human population, and global versus regional invasion patterns

Listen to a brief audio clip by author Qinfeng Guo describing this publication. • Text Transcript

Abstract

Context Biological invasions are among the greatest global and regional threats to biomes in the Anthropocene. Islands, in particular, have been perceived to have higher vulnerability to invasions. Because of the dynamic nature of ongoing invasions, distinguishing regional patterns from global patterns and their underlying determinants remains a challenge. Objectives We aim to comparatively examine global versus regional patterns of plant invasions and the possible underlying mechanisms. We also test whether there is a difference in degree of invasion and invasibility between mainland areas and islands. Methods We compiled and analyzed data from published sources for 100 mainland areas (i.e., regions, countries, states, and provinces) and 89 islands across the globe. Results We find that (1) the pool of exotic species available intrinsically decreases as area of the land considered increases (at global scale, all is native), thus global invasion patterns assessed by exotic fraction (proportion of exotics) are primarily determined by land area; (2) because ‘‘exotic’’ is defined relative to the borders of the target region, ‘‘boundary effects’’ can result in regional differences in invasion patterns without any ecological processes being involved; and (3) human population density is closely linked to exotic fraction within regions that are defined by a single administrative border. Conclusions There were clear differences between global and regional patterns of plant invasions. We observed no difference in the exotic fraction-area relationship between mainland areas and islands, supporting what we refer to as the ‘‘island-mainland continuum concept’’ (i.e., no clear separation in the degree of invasion between islands and mainland area with regard to the effects of area). Because of scaledependency in many observed patterns, future focus should be placed on the links between local, regional, and global invasion patterns.

  • Citation: Guo, Qinfeng; Iannone III, Basil V.; Nunez-Mir, Gabriela C.; Potter, Kevin M.; Oswalt, Christopher M.; Fei, Songlin 2017.Species pool, human population, and global versus regional invasion patterns. Landscape Ecology. 32(2): 229-238. https://doi.org/10.1007/s10980-016-0475-6.

Requesting Publications

You can request print copies of our publications at this email address: pubrequest@fs.fed.us

Publication Notes

  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
  • Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unuseable.
  • To view this article, download the latest version of Adobe Acrobat Reader.