Quantitative population and community dynamics

人口和社区动态定量

• 批准号: RGPIN-2020-03936
• 负责人: Fox, Jeremy
• 金额: $ 4.01万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=739575
• 关键词: Quantitative; population; community; dynamics

On ecological timescales, the distribution and abundance of species depends on local species interactions like competition which determine birth and death rates, and dispersal among local sites. The focus of my research program is to understand how larger-scale patterns in ecology emerge from the fundamental processes that determine abundances: birth, death, and movement. This is a challenging problem because rates of birth, death, and movement depend on many factors and can vary greatly among species, locations, and times. My proposal describes two short-term objectives that further my long-term research program: (1) Spatial synchrony. One of the most striking large-scale patterns in ecology is spatial synchrony: spatially-separated populations of the same species all increasing, and decreasing, in abundance in concert, even though some populations are hundreds or even thousands of km from others. Species as different as birds, insects, and human pathogens exhibit spatial synchrony, suggesting that the explanation for synchrony lies in general principles rather than system-specific biology. Building on my previous work, I propose to test previously-untested hypotheses for how spatial synchrony arises from movement of organisms from place to place, and from spatially-synchronized weather fluctuations. If the proposed hypotheses hold, much current thinking will require revisiting. (2) Species coexistence. Competing species from microbes to mammals often coexist for many generations. The mechanisms explaining coexistence often are system-specific. To identify general principles, modern coexistence theory summarizes the consequences of these system-specific mechanisms in terms of a smaller set of abstract, "higher level" mechanisms that can be quantified in any system. New methods make it feasible to quantify these high-level mechanisms. I propose to test hypotheses about how environmental fluctuations, and the number of coexisting species, mediate the strength of high-level coexistence mechanisms. Few studies test hypotheses about the strengths of coexistence mechanisms. I propose to address both objectives with laboratory microcosm communities comprised of fast-growing protists and bacteria. This system allows me to directly manipulate the hypothesized determinants of spatial synchrony and species coexistence, manipulations that are impossible in most other systems. Laboratory microcosms play by the same fundamental rules as natural systems. Microcosm experiments complement field studies by allowing powerful, direct experimental tests of hypothesized general principles. Those general principles apply to species in Canada and elsewhere. Understanding general principles underpins our ability to conserve and manage Canadian species and ecosystems. Besides contributing to fundamental understanding, the proposed work will provide training and research experience for 3 Ph.D. students, 3 M.Sc. students, and 13 undergraduate research assistants.

在生态时间尺度上，物种的分布和丰度取决于当地物种的相互作用，如竞争，决定出生率和死亡率，以及在当地地点之间的扩散。我的研究计划的重点是了解生态学中的大规模模式是如何从决定丰度的基本过程中出现的：出生，死亡和运动。这是一个具有挑战性的问题，因为出生率，死亡率和运动取决于许多因素，并且在物种，地点和时间之间可能存在很大差异。 我的建议描述了两个短期目标，进一步我的长期研究计划：（1）空间同步。生态学中最引人注目的大尺度模式之一是空间同步性：同一物种在空间上分离的种群都在一致地增加或减少，即使一些种群与其他种群相距数百甚至数千公里。像鸟类、昆虫和人类病原体这样不同的物种都表现出空间同步性，这表明对同步性的解释在于一般原则，而不是系统特异性生物学。在我以前的工作的基础上，我建议测试以前未经测试的假设，空间同步如何产生从一个地方到另一个地方的生物体的运动，并从空间同步的天气波动。如果所提出的假设成立，那么当前的许多想法都需要重新审视。(2)物种共存。从微生物到哺乳动物的竞争物种通常会共存许多代。解释共存的机制往往是系统特有的。为了确定一般原则，现代共存理论总结了这些系统特定机制的后果，这些机制是一组更小的抽象的，“更高层次”的机制，可以在任何系统中量化。新的方法使得量化这些高级机制变得可行。我建议测试的假设环境波动，以及共存物种的数量，调解高层次的共存机制的强度。很少有研究测试共存机制的强度的假设。 我建议通过由快速生长的原生生物和细菌组成的实验室微观群落来解决这两个目标。这个系统允许我直接操纵空间同步和物种共存的假设决定因素，这在大多数其他系统中是不可能的。实验室的微观世界遵循着与自然系统相同的基本规则。微观世界实验通过对假设的一般原理进行强有力的、直接的实验测试来补充实地研究。这些一般原则适用于加拿大和其他地方的物种。了解一般原则是我们保护和管理加拿大物种和生态系统的能力的基础。 除了有助于基本的理解，拟议的工作将提供培训和研究经验，3博士。学生，3名硕士生，13名本科研究助理。