栖息地毁坏和生物入侵被认为是全球物种多样性的两大威胁,也是当前研究的热点.同时,两者的共同作用将比单独作用所带来的物种多样性丧失更大.本文基于竞争-扩散均衡机制,考虑了外来种的不同竞争力,结合景观中性模型和元胞自动机模型,模拟了外来种入侵对栖息地毁坏(栖息地破碎和面积丧失)的响应.研究结果表明:1)外来种入侵成功将首先威胁竞争力与其相邻的弱物种；2)栖息地毁坏与种间竞争共同决定着外来种入侵的成功与否.当栖息地破碎促进了与外来种竞争力相邻的本地强物种时,将会抑制入侵；当其抑制了与外来种竞争力相邻的本地强物种时,则会促进入侵.当栖息地丧失促进了外来种相邻的本地强物种时,将会抑制入侵；当栖息地丧失抑制了外来种相邻的本地强物种,将一定程度地促进入侵,但随着丧失面积的增加,则转为抑制.因此,为了抑制不同竞争力的外来种入侵,应采取不同的栖息地保护策略,并保护和促进其竞争力相邻的本地强物种.%Biological invasion and habitat destruction, especially for their interactive effects are recognized as the major factors of species extinction. Based on dispersal-competition trade-off, we have simulated the effects of competitive abilities on invasion and the responses of alien species with different competitive abilities to habitat destruction by incorporating cellular automaton with landscape neutral model. The results show that: 1) the introductions of alien species will threaten the species with similar competitive ability firstly, and then the poorer competitors. 2) Whether the invasion will succeed or fail is dependent on the interaction between habitat destruction and the competition between native and alien species. When habitat fragmentation promotes the native superior competitor next to exotic species, it will inhibit invasion. On the contrary, when it inhibits the superior one, it will promote invasion. When habitat loss promotes the superior one, it will inhibit invasion. However, when it inhibits the superior one, it will promote firstly, and then inhibit invasion as it increases. To prevent invasion of exotic species with different competitive abilities, different management policies of habitat conservation should be taken, furthermore, their adjacent superior competitors should be protected and further developed.
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