Special feature: alien pests threatening biodiversity of forest ecosystems

摘要

Throughout the world, biological invasions have become one of the most important factors threatening biodiversity. Many species are introduced into "a new world" accidentally or intentionally. Most fail to become established, but some become established, colonize, and start to increase and expand their ranges. Some invasive pathogens damage and kill host species. Some invasive herbivores destroy vegetation by feeding and killing host plants. Some invasive carnivores extinguish their prey by depressing their density below the minimum viable population. Some domestic species are replaced by or hybridize with invasive species in a similar niche. The effects of invasive species are more than these direct effects. They cause cascading changes in the ecology, function, and value of diverse ecosystems.