Dissertation Research: Influence of Priority Effects on Community Assembly in Fragmented Habitats

优先效应——群落中已经存在的物种对后来到达的物种成功定殖的影响——在生态群落的形成（群落聚集）过程中是重要的。由于生境破碎化的加剧，了解优先效应的影响是否可以在不同地点推广是很重要的。提出的研究在一个模型系统中检验了优先效应：居住在亚利桑那州杂酚灌木中的昆虫和蜘蛛群落。实验将在两种生境类型（即沙漠残余物和外围沙漠地区）进行，这两种生境类型在破碎化程度、多样性、干扰后的恢复以及对优先效应的反应方面存在差异。研究将调查两种掠夺性先驱殖民者对社区恢复的影响，并确定在社区集会中可检测到的优先效应有多长时间。这种研究群落生态学的方法将说明物种聚集过程中初始条件的重要性，这将有助于在碎片化栖息地中工作的恢复生态学家。

Priority effects - influences of species already present in a community on the successful colonization by later arriving species - are important during the formation of ecological communities (community assembly). Because of increasing habitat fragmentation, it is important to understand whether the influence of priority effects can be generalized across locations. The proposed research examines priority effects in a model system: insect and spider communities inhabiting creosote bush in Arizona. Experiments will be conducted in two habitat types (i.e., desert remnants and outlying desert areas) that previous research found to differ in degree of fragmentation, diversity, recovery following disturbance, and response to priority effects. Research will investigate the influence of two predatory pioneer colonists on community recovery and determine how long priority effects are detectable in community assembly. This approach to community ecology will illustrate the importance of initial conditions during species assembly that will be useful to restoration ecologists working in fragmented habitats.