集合种群动态对栖息地毁坏时空异质性的响应

栖息地毁坏既有时间异质性,也有空间异质性,而以往的研究往往只关注其中的一种。将两种不同的异质性共同引入到元胞自动机中,模拟了集合种群动态对栖息地毁坏时空异质性的响应。发现,在随机离散的栖息地毁坏下,由于物种的迁移繁殖力受栖息地毁坏的影响很大,迁移繁殖力弱而竞争力强的物种先灭绝。在连续的栖息地毁坏下,物种的迁移繁殖力受栖息地毁坏的影响较小,物种的灭绝由竞争力和迁移繁殖力共同决定:在有绝对优势种的群落里,种间竞争显著,弱物种先灭绝,而在没有绝对优势种的群落里,种间竞争较小,则以强物种先灭绝。因此,随机毁坏不利于强物种续存,而连续毁坏则不利于具有绝对优势种群的群落里的弱物种续存。在实际开发某一栖息地时,根据集合种群结构和被保护的对象采取相应的开发模式。

Response of metapopulation dynamics to the temporal-spatial heterogeneity of habitat destruction

Habitat destruction is the primary cause of extinction.There are two broad categories of the heterogeneity of habitat destruction:spatial and temporal heterogeneities.Previous studies mostly focus on one category and do not integrate one with the other.Therefore,we integrate the spatial heterogeneity with the temporal heterogeneity into cellular automata to study the response of metapopulation dynamics to the temporal-spatial heterogeneity of habitat destruction.The results show that:under random and discrete habitat destruction,superior competitors,but poorer colonizers,will go extinct first because their colonization abilities are deeply affected by habitat destruction.Under continuous destruction,however,colonization abilities are affected slightly by habitat destruction,and species extinction is determined by competition abilities and colonization abilities together.In the community with absolute dominance species and good colonization ability,inferior competitors will go extinct first due to strong specific-competition.While in the community without dominant species and with poor colonization ability,superior competitors will go extinct first due to poor specific-competition.Therefore,random destruction is not favorable to the persistence of superior competitors,while continuous destruction is not favorable to the persistence of inferior competitors in the community with good colonization ability.So,when exploiting a certain habitat,we should take different action according to different conservation objects and metapopulation with different structures.