Plant Invasions in China: What Is to Be Expected in the Wake of Economic Development?

M ost developing countries are located at low latitudes and thus share a substantial part of the world's biological diversity, because species richness increases toward the equator. However, economic pressure and habitat degradation in these countries pose serious threats to the conservation of species and habitats Another major threat is the spread of invasive alien species, defined as "alien species whose establishment and spread threaten ecosystems, habitats or species with economic or environmental harm" Invasive alien plant species can transform species-rich native animal and plant communities into species-poor stands dominated by these alien species. One example is the North American grass Spartina alterniflora, which is invading coastal wetlands in China (figure Invasive species cause high costs The spread of invasive species is strongly linked to human activities (e.g., species introductions and habitat degradation). Species introductions, both intentional and accidental, are usually the result of trade, which delivers species to new regions where they may become established. Degradation by disturbances such as fire, grazing, or urbanization can make habitats suitable for alien weeds; such degradation often precedes an invasion