Collaborative Research: Mathematical and Experimental Analysis of Competitive and Predator-Prey Models: Conditional Dispersal on Patches to Landscapes

合作研究：竞争模型和捕食者-被捕食模型的数学和实验分析：景观斑块的条件扩散

• 批准号: 2150945
• 负责人: Ratnasingham Shivaji
• 金额: $ 8万
• 依托单位: University of North Carolina Greensboro
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2150945&HistoricalAwards=false
• 关键词: Collaborative; Research; Mathematical; Experimental; Analysis

Long-term survival and coexistence of species in the face of habitat loss and fragmentation is among the most critical concerns faced by ecologists today. This project is an integration of mathematical modeling and experimental analysis of an insect herbivore and predator system to explore the effects of habitat fragmentation, interspecific competition, and predation on the population dynamics and coexistence of species from the patch to the landscape level. Results from this project aim to answer two key ecological questions: (1) For competing species, what effect does the density of the same or different species have on dispersal-reproduction and dispersal competition tradeoffs arising from the evolution of dispersal in fragmented habitats? (2) How does the presence of a shared predator affect the relationship between density and emigration, tradeoffs involving dispersal? The project will also provide significant contributions towards the analysis of mathematical models created to study this behavior via development of new mathematical tools to better understand model dynamics. Finally, results from this study are expected to be applicable to conservation programs and reserve design. This project will involve the training of graduate and undergraduate students through PI-hosted workshops and mentorship of independent research projects. Moreover, an app that estimates key dispersal parameters from field data will be created and made publicly available.This collaborative project comprises integrated reaction-diffusion modeling, mathematical analysis, and experimental research to explore the effects of habitat fragmentation, conditional dispersal, interspecific competition, and predation on the population dynamics and species coexistence from the patch to the landscape level. The Investigators will use diffusive Lotka-Volterra competition and predator-prey systems with nonlinear boundary conditions modeling density dependent emigration (DDE) at the patch and landscape levels. Experiments will be performed using two Tribolium flour beetle species to examine how the DDE relationship and life-history tradeoffs are affected by a shared predator (Xylocoris flavipes). This project is expected to be novel and significant by providing (1) experimental evidence that interspecific competitors and predators affect boundary behavior, the strength and form of DDE, and important life-history tradeoffs linked to species coexistence; (2) the first theoretical framework for the effects of conditional dispersal on the population dynamics and coexistence of competing species and a shared predator in fragmented landscapes; and (3) a significant contribution toward the analysis of systems of elliptic boundary value problems with nonlinear boundary conditions, as new mathematical tools will be developed to better understand the models’ dynamics. Knowledge of species’ life histories, coupled with predictions regarding how competitors and predators can alter the magnitude and form of DDE and life history tradeoffs, can help determine whether existing reserves are adequate for species long-term coexistence.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

面对栖息地丧失和破碎化，物种的长期生存和共存是当今生态学家面临的最关键问题之一。该项目整合了昆虫食草动物和捕食者系统的数学模型和实验分析，以探索栖息地破碎化、种间竞争和捕食对从斑块到景观水平的种群动态和物种共存的影响。该项目的结果旨在回答两个关键的生态问题：（1）对于竞争物种，相同或不同物种的密度对分散栖息地的分散演化所产生的分散繁殖和分散竞争权衡有何影响？ (2) 共同捕食者的存在如何影响密度与迁出、涉及扩散的权衡之间的关系？该项目还将通过开发新的数学工具来更好地理解模型动力学，为研究这种行为而创建的数学模型的分析做出重大贡献。最后，这项研究的结果预计适用于保护计划和保护区设计。该项目将通过 PI 主办的研讨会和独立研究项目的指导来培训研究生和本科生。此外，还将创建一个根据现场数据估计关键扩散参数的应用程序并公开。该合作项目包括综合反应扩散模型、数学分析和实验研究，以探索栖息地破碎化、条件扩散、种间竞争和捕食对从斑块到景观水平的种群动态和物种共存的影响。研究人员将使用扩散的 Lotka-Volterra 竞争和捕食者-被捕食者系统，以及非线性边界条件，在斑块和景观水平上模拟密度相关的迁移（DDE）。将使用两种谷盗粉甲虫物种进行实验，以研究共同捕食者（Xylocoris flavipes）如何影响 DDE 关系和生活史权衡。该项目预计将是新颖且重要的，因为它提供了（1）实验证据，表明种间竞争者和捕食者影响边界行为、DDE的强度和形式，以及与物种共存相关的重要生活史权衡； (2) 第一个理论框架，研究有条件扩散对破碎景观中种群动态以及竞争物种和共同捕食者共存的影响； （3）对具有非线性边界条件的椭圆边值问题系统的分析做出重大贡献，因为将开发新的数学工具以更好地理解模型的动力学。了解物种的生活史，再加上对竞争者和捕食者如何改变 DDE 的程度和形式以及生活史权衡的预测，可以帮助确定现有保护区是否足以维持物种的长期共存。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。