Contributions of demography and dispersal parameters to the spatial spread of a stage-structured insect invasion.
Contributions of demography and dispersal parameters to the spatial spread of a stage-structured insect invasion.
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人口统计学和传播参数对阶段结构昆虫入侵空间传播的贡献。
DOI：
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发表时间：
2010
影响因子：
5
通讯作者：
B. Tenhumberg
中科院分区：
文献类型：
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作者：
T. Miller;B. Tenhumberg
阶段结构模型，整合人口和扩散，可用于确定点的生命周期中的人口空间扩散率，信息是至关重要的遏制战略的发展，入侵物种的影响很大。目前，这些工具的应用面临的挑战包括：（1）考虑模型参数的大的不确定性，这可能会违反“局部”扰动指标，如灵敏度和弹性的假设，（2）不仅预测空间传播的渐近速率，通常是这样做的，而且在入侵的早期阶段的瞬态空间动态。我们开发了一个入侵模型的Diaprepes根象甲（DRW; Diaprepes rectuatus [鞘翅目：金龟子科]），一个多面手的食草动物入侵柑橘种植区的美国。我们综合了DRW人口统计学和扩散数据，并对渐近和瞬时峰值入侵速度进行了预测，考虑了参数的不确定性。我们量化的贡献，每个参数对入侵速度使用“全球”扰动分析，我们对比参数的贡献在瞬态和渐近阶段。我们发现，渐近侵入速度为0.02-0.028公里/周，虽然瞬时峰值侵入速度（0.03-0.045公里/周）显着更大。渐近和瞬态入侵速度是最敏感的象鼻虫扩散距离。然而，对渐近速度有很大影响的人口统计参数（例如，早期幼虫的存活）对瞬时速度的影响很小。全球分析与较低水平的弹性比较表明，局部扰动分析会产生不可靠的预测入侵速度的基本参数的响应。在南部佛罗里达（1992年至2006年）观察到的范围扩展显着低于模型预测的入侵速度。这种不匹配的可能原因包括高估的散布距离，人口统计率，和时空变化的参数值。这项研究表明，当参数的不确定性是大的，往往是这样，全球扰动分析，需要确定在生命周期中的点应该是管理的目标。我们的研究结果还表明，在渐进阶段减少传播的有效策略在瞬时阶段可能影响不大。
Stage-structured models that integrate demography and dispersal can be used to identify points in the life cycle with large effects on rates of population spatial spread, information that is vital in the development of containment strategies for invasive species. Current challenges in the application of these tools include: (1) accounting for large uncertainty in model parameters, which may violate assumptions of "local" perturbation metrics such as sensitivities and elasticities, and (2) forecasting not only asymptotic rates of spatial spread, as is usually done, but also transient spatial dynamics in the early stages of invasion. We developed an invasion model for the Diaprepes root weevil (DRW; Diaprepes abbreviatus [Coleoptera: Curculionidae]), a generalist herbivore that has invaded citrus-growing regions of the United States. We synthesized data on DRW demography and dispersal and generated predictions for asymptotic and transient peak invasion speeds, accounting for parameter uncertainty. We quantified the contributions of each parameter toward invasion speed using a "global" perturbation analysis, and we contrasted parameter contributions during the transient and asymptotic phases. We found that the asymptotic invasion speed was 0.02-0.028 km/week, although the transient peak invasion speed (0.03-0.045 km/week) was significantly greater. Both asymptotic and transient invasions speeds were most responsive to weevil dispersal distances. However, demographic parameters that had large effects on asymptotic speed (e.g., survival of early-instar larvae) had little effect on transient speed. Comparison of the global analysis with lower-level elasticities indicated that local perturbation analysis would have generated unreliable predictions for the responsiveness of invasion speed to underlying parameters. Observed range expansion in southern Florida (1992-2006) was significantly lower than the invasion speed predicted by the model. Possible causes of this mismatch include overestimation of dispersal distances, demographic rates, and spatiotemporal variation in parameter values. This study demonstrates that, when parameter uncertainty is large, as is often the case, global perturbation analyses are needed to identify which points in the life cycle should be targets of management. Our results also suggest that effective strategies for reducing spread during the asymptotic phase may have little effect during the transient phase.