Ecosystem engineers: modelling organism-environment feedback

预测种群规模和空间分布是生物控制、渔业、疾病、野生动物、入侵物种和濒危物种管理计划的核心。毫无疑问，非生物环境条件是种群动态的重要决定因素。然而，一些物种对自然环境有很大的影响，从而改变了种群。例如，植物建筑在空间中创造了物理结构，这可能会改变生物附近的非生物因素（如风速）。这种自然环境的改变可能影响植物自身的种群和其他物种的种群。在我的研究计划中，我研究了环境的小尺度时空结构对种群动态和传播的影响。更重要的是，我还研究生物体本身如何创造或修改这种结构，以预测生物体和物理环境之间的这种反馈如何改变我们管理种群的能力。我提出三个子项目，每个子项目都涉及这个整体研究计划的各个方面。首先，我将开发一个简单而通用的建模框架来描述生物体和物理环境之间的反馈。其次，我将研究气候变化的作用，以及气候条件下的生物修饰，在确定非本地物种的建立概率和传播率方面。最后，我建议开发和测试通用模型，以预测植物结构对蚜虫等害虫的影响，以及有益捕食者（如微小的盗蝽和草蛉）控制这些农业害虫的能力。这些项目将共同提供理论和实验数据，这些数据可能证明在预测种群动态时考虑生物-环境相互作用的重要性。

Predicting population size and spatial distribution lies at the heart of management plans for biological control, fisheries, disease, wildlife, invasive species, and endangered species. It is no surprise that abiotic environmental conditions are important determinants of population dynamics. However, some species have large effects on the physical environment which alter populations. For example, plant architecture creates physical structure in space, which may alter abiotic factors (e.g., wind speed) in the immediate vicinity of the organism. This alteration of the physical environment may impact both the plant's own population and the populations of other species. In my research program, I investigate the effects of small-scale spatial and temporal structure of the environment on the dynamics and spread of populations. More importantly, I also study how organisms themselves create or modify this structure in order to predict how such feedback between organisms and physical environment alters our ability to manage populations. I propose three subprojects that each address aspects of this overall research program. First, I will develop a simple and general modelling framework to describe the feedback between organisms and physical environment. Second, I will examine the role of climate variation, and organism modification of climate conditions, in determining establishment probabilities and spread rates of non-native species. Finally, I propose to develop and test general models which predict the effects of plant architecture on the pest species such as aphids, and the ability beneficial predators, such as minute pirate bugs and lacewings, to control these agricultural pests. Together these projects will provide both theory and experimental data which may demonstrate the importance of considering organism-environment interactions when predicting population dynamics.