Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, 100193, China.
Centre for Invasion Biology, Department of Mathematical Sciences, Stellenbosch University, Matieland, 7602, South Africa.
Ecology. 2019 May;100(5):e02682. doi: 10.1002/ecy.2682. Epub 2019 Apr 24.
Biological invasions are increasingly being considered important spatial processes that drive global changes, threatening biodiversity, regional economies, and ecosystem functions. A unifying conceptual model of the invasion dynamics could serve as a useful tool for comparison and classification of invasion processes involving different species across large geographic ranges. By dividing these geographic ranges that are subject to invasions into discrete spatial units, we here conceptualize the invasion process as the transition from pristine to invaded spatial units. We use California cities as the spatial units and a long-term database of invasive tropical tephritids to characterize the invasion patterns. A new life-table method based on insect demography, including the progression model of invasion stage transition and the species-specific partitioning model of multispecies invasions, was developed to analyze the invasion patterns. The progression model allows us to estimate the probability and rate of transition for individual cities from pristine to infested stages and subsequently differentiate the first year of detection from detection recurrences. Importantly, we show that the interval of invasive tephritid recurrence in a city declines with increasing invasion stages of the city. The species-specific partitioning model revealed profound differences in invasion outcome depending on which tephritid species was first detected (and then locally eradicated) in the early stage of invasion. Taken together, we discuss how these two life-table invasion models can cast new light on existing invasion concepts; in particular, on formulating invasion dynamics as the state transition of cities and partitioning species-specific roles during multispecies invasions. These models provide a new set of tools for predicting the spatiotemporal progression of invasion and providing early warnings of recurrent invasions for efficient management.
生物入侵越来越被认为是推动全球变化的重要空间过程，威胁着生物多样性、区域经济和生态系统功能。一个统一的入侵动态概念模型可以作为一种有用的工具，用于比较和分类涉及不同物种在大地理范围内的入侵过程。通过将受入侵影响的这些地理范围划分为离散的空间单元，我们将入侵过程概念化为从原始状态到被入侵状态的转变。我们使用加利福尼亚的城市作为空间单元，并利用热带入侵果实蝇的长期数据库来描述入侵模式。我们开发了一种基于昆虫种群动态的新生命表方法，包括入侵阶段转变的进展模型和多物种入侵的物种特异性划分模型，用于分析入侵模式。进展模型使我们能够估计单个城市从原始状态到受感染状态的过渡概率和速率，并随后区分首次检测到的时间与后续的重复检测时间。重要的是，我们表明，城市中入侵果实蝇的重复出现间隔随着城市入侵阶段的增加而减少。物种特异性划分模型揭示了入侵结果的深刻差异，具体取决于在入侵早期阶段首先检测到（然后在当地根除）的哪种果实蝇物种。总的来说，我们讨论了这两个生命表入侵模型如何为现有的入侵概念提供新的视角；特别是，将入侵动态表述为城市的状态转变，以及在多物种入侵中划分物种特异性角色。这些模型为预测入侵的时空进展和提供复发性入侵的早期预警提供了一套新工具，以便进行有效的管理。
