Biological Invasions in Nature Reserves in China

Abstract

One consequence of the rapid economic development in China is the rapid increase in the ecological threats posed by alien species. Nature reserves serve as barriers to species invasions, but there is now no reserve in the world that is free from introduced alien species. In this chapter, we review studies of alien species invasions in nature reserves of China, analyze the invasion pattern across reserves, and propose suggestions for the management of invasive species in nature reserves in China. By searching available databases, we found a total of 37 studies focusing on biological invasions in 24 nature reserves in China. The Dinghushan Nature Reserve has the largest number of invasive species, followed by Taohongling, Tianmushan and Ganshiling reserves, whereas Yiwulvshan, Yalujiangkou and Dayudao have the fewest invasive plant species. Alternanthera philoxeroides, Amaranthus spinosus and Euphorbia hirta are the species most frequently reported to occur in nature reserves, while Compositae, Amaranthaceae and Gramineae are the three most frequently reported families. The number of invasive species reported declines with increasing latitude, but is not significantly correlated with reserve age, elevation, or area. We analyzed an index of invasion (the ratio of invasive to total plant species), which increases with nature reserve age, and decreases with elevation and the number of plant species in reserves; the effect of elevation, however, is not detected when controlling for the number of plant species or reserve area. When controlling for the effect of reserve area, the number of invasive species is positively correlated with the total number of plant species. Although manual, chemical, mechanical, and biological methods have been suggested for the control or eradication of invasive species, each method has its own limitation. We suggest that global changes and disturbances (e.g., N deposition) should be taken into account when assessing the risk of alien species and designing management strategies.