Collaborative Research: QEIB: Spatial Ecologies Under Temporal Variation

入侵物种威胁到农业生产力和公众健康，并可能进一步破坏某些本地生态系统的物种组成。根据定义，一个入侵物种的种群必须从它的引入点开始发展。因此，生态学家和保护生物学家寻求对成功的入侵者空间增长模式的预测性理解。提出的研究将把生物入侵作为一种前沿移动，在二维环境中有一些随机变化。理论和实验都将明确地考虑生态上优越的入侵者与本地居住物种的竞争。这两个物种空间聚集生长模型的细节允许应用统计物理学中发展起来的动力学粗化理论来预测入侵过程的定量行为。研究结果对入侵锋的推进速度和最远入侵点进入栖息地的相对位置提出了新的假设。这些数量的期望值取决于入侵前线的长度；因此，它们可预见地依赖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，将研究时变环境中的空间竞争。田间试验，使用黑麦草-三叶草系统，将被用来检验由模型产生的假设。更好地理解个体层面的相互作用与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。该研究计划强调在研究生和本科阶段对青年科学家进行教育和培训。该研究的协作性、跨学科性质将提高生态学学生的定量分析能力，并将向物理学学生介绍生态学和自然保护领域的当代挑战。

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.