Collaborative Research: QEIB: Spatial Ecologies Under Temporal Variation

入侵物种威胁农业生产力和公共健康，并可能进一步破坏某些本土生态系统的物种组成的稳定。根据定义，入侵物种的种群必须从其引入点开始前进。因此，生态学家和保护生物学家寻求对成功入侵者的空间生长模式的预测性理解。拟议的研究将通过二维环境将生物入侵视为前沿移动，并具有一些随机变化。理论和实验都将明确考虑生态优越的入侵者与本地居民物种的竞争。这两个物种的空间集群生长模型的细节允许应用统计物理学中发展的动力学粗糙化理论来预测入侵过程的定量行为。结果产生了关于入侵前沿前进速度和最远入侵入侵居民栖息地的相对位置的新假设。这些量的预期值取决于入侵锋面的长度；因此，它们可以预见地取决于被入侵栖息地的线性大小。一旦确定了恒定物理环境的结果，就会研究随时间变化的环境中的空间竞争。使用黑麦草-三叶草系统的现场实验将用于测试模型生成的假设。更好地了解个体层面的相互作用和种群空间增长之间的联系将提高我们预测入侵物种、新出现的感染和进化适应如何在生态景观中传播的能力。该研究计划强调研究生和本科生年轻科学家的教育和培训。该研究的协作、跨学科性质将提高生态学学生的定量技能，并将向物理系学生介绍当代生态学和保护方面的挑战。

Invasive species threaten agricultural productivity and public health, and may further destabilize the species composition of certain native ecosystems. An invading species' population, by definition, must advance from its point of introduction. Consequently, ecologists and conservation biologists seek a predictive understanding of a successful invader's pattern of spatial growth. The proposed research will address biological invasion as a front moving, with some random variation, through a two-dimensional environment. Both the theory and experimentation will explicitly consider an ecologically superior invader competing with a native, resident species. Details of the model for spatially clustered growth of the two species permit application of the theory of kinetic roughening, developed in statistical physics, to predict the quantitative behavior of the invasion process. The results generate novel hypotheses concerning both the velocity of the invasive front's advance and the relative position of the furthest invasive incursion into the resident's habitat. Expected values of these quantities depend on the length of the invading front; hence they depend predictably on the linear size of the habitat invaded. Once results for a constant physical environment have been identified, spatial competition in a time-varying environment will be investigated. Field experiments, using a rye grass-clover system, will be used to test hypotheses generated by the models.A greater understanding of links between individual-level interactions and a population's spatial growth will increase our ability to predict how invasive species, emerging infections, and evolutionary adaptations spread across ecological landscapes. The research plan emphasizes education and training of young scientists at both graduate and undergraduate levels. The collaborative, interdisciplinary nature of the research will enhance quantitative skills of ecology students, and will introduce contemporary challenges in ecology and conservation to physics students.