Multiple introductions are hypothesized to facilitate the success of invasive plant species, because they can result in novel genotypes through intraspecific hybridization potentially increasing the ability to adapt to the novel environment. In this study, we address the question of how the demography of an invader with multiple introductions and intraspecific hybridization varies across sites. This was done by modeling the population dynamics of Brazilian pepper, Schinus terebinthifolia Raddi (Anacardiaceae), a shrub native to Brazil, Paraguay and Argentina that has invaded the global subtropics and was introduced to Florida on two separate occasions. This species exhibits variability in growth form such that vertical and lateral growth are not strongly associated. Our demographic field work took place at six sites spanning the introduced range in Florida and differing in introduction history. For each site we constructed integral projection models where the probabilities of survival, growth and reproduction were modeled as functions of two different metrics of size, the continuous variables diameter and height, metrics of vertical and lateral growth, respectively. We performed a Life Table Response Experiment analysis to decompose the effects of variation among sites in vital rates on the population dynamics of S. terebinthifolia. We found that spatial variation in population dynamics was driven primarily by site-level differences in the maturation of seedlings into reproductive adults. The survival and growth of the largest individuals had the highest elasticity, suggesting that management actions capable of decreasing these vital rates would have the greatest effect on reducing the population growth rate.

假设多次引入有助于入侵植物的成功，因为它们可以通过种内杂交产生新的基因型，从而潜在地增加了适应新环境的能力。在这项研究中，我们解决了一个问题，即多次引入和种内杂交的入侵者的人口统计在不同站点之间如何变化。这是通过对巴西胡椒（Schinus terebinthifolia）的种群动态进行建模来完成的Raddi（Anacardiaceae），一种原产于巴西，巴拉圭和阿根廷的灌木，曾入侵全球亚热带，并两次被引入佛罗里达。该物种在生长形式上表现出可变性，因此垂直和横向生长没有强烈的联系。我们的人口统计学现场工作在六个地点进行，这些地点跨越佛罗里达州的引进范围，并且在引进历史上有所不同。对于每个站点，我们构建了整体投影模型，其中将生存，生长和繁殖的概率建模为两个不同大小指标（连续变量直径和高度，垂直和横向生长指标）的函数。我们进行了生命表响应实验分析，以分解生命率各部位之间的变化对沙特阿拉伯种群动态的影响。沙门氏菌。我们发现种群动态的空间变化主要是由幼苗成熟到繁殖成年的位点水平差异驱动的。最大个体的生存和增长具有最高的弹性，这表明能够降低这些生命率的管理措施对降低人口增长率的影响最大。