Collaborative Research: Mathematical and Experimental Analysis of Competitive Ecological Models: Patches, Landscapes, Stage Structure, and Conditional Dispersal on the Boundary

合作研究：竞争性生态模型的数学和实验分析：斑块、景观、阶段结构和边界上的条件扩散

• 批准号: 1853352
• 负责人: Ratnasingham Shivaji
• 金额: $ 23.9万
• 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: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1853352&HistoricalAwards=false
• 关键词: Collaborative; Research; Mathematical; Experimental; Analysis

In our increasingly fragmented world, dispersal between habitat fragments is essential for the long-term survival of a species. This project will integrate mathematical modeling and experimental analysis of an insect commonly found in stored grains to describe the effects of habitat fragmentation, conditional dispersal (e.g. an organism?s decision to leave a fragment depends upon competitor presence) and interspecific competition on population dynamics from the patch level to the landscape level. Results from this project will answer key ecological questions including: What effects do competitors have on the emigration behavior of species at patch boundaries? How do relationships between density and emigration affect regional population dynamics and competitor coexistence? How does conditional dispersal affect competition-dispersal tradeoffs that are thought to be a key to competitor coexistence? The project will advance the analysis of mathematical models created to answer these questions and better understand model dynamics. Finally, results from this study will apply to conservation programs and habitat reserve design. Graduate and undergraduate students will be trained through PI-hosted workshops and mentorship of independent research projects. Project results will be disseminated to both ecological and mathematical communities through peer-reviewed journals, national and international conference talks, and a user-friendly website. Additionally, an app that estimates key dispersal parameters from field data will be created and made publicly available. This project is funded jointly by the Division of Mathematical Sciences Mathematical Biology program and the Division of Environmental Biology Population and Community Ecology program.This collaborative project will integrate reaction-diffusion models, mathematical analysis, and experimental analysis to explore the effects of habitat fragmentation, conditional dispersal and interspecific competition on the population dynamics and species coexistence from the patch to the landscape level. The PIs will use diffusive Lotka-Volterra competition systems with nonlinear boundary conditions modeling density dependent emigration (DDE) both at the patch and landscape levels and stage structure. Ongoing research suggests that life-history traits, such as whether a species is solitary or gregarious, can provide cues as to the form of DDE for particular species. Knowledge of species' life histories, coupled with our predictions regarding how different forms of DDE can affect species coexistence and connectivity among habitat patches, can help determine whether existing reserves are adequate for species coexistence. Dispersal experiments will be performed using two Tribolium flour beetle species to parameterize the models and compare model predictions about coexistence and stability with results from long-term experiments. Innovative contributions will be made by providing (1) experimental evidence that interspecific competitors affect within-patch redistribution, boundary behavior and the strength and form of the DDE relationship; (2) the first theoretical framework and empirical evidence for the effects of conditional dispersal on the population dynamics and coexistence of competing species in fragmented landscapes; and (3) novel analysis of elliptic boundary value problems with nonlinear boundary conditions.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.

在我们这个日益碎片化的世界里，栖息地碎片之间的分散对于一个物种的长期生存至关重要。该项目将整合数学建模和实验分析的一种常见的昆虫在存储的谷物，以描述栖息地破碎化的影响，条件扩散（例如，一个有机体？的决定，离开一个片段取决于竞争对手的存在）和种间竞争的种群动态从斑块水平景观水平。该项目的结果将回答关键的生态问题，包括：竞争对手对物种在斑块边界的迁移行为有什么影响？人口密度和移民之间的关系如何影响区域人口动态和竞争者共存？条件分散如何影响竞争分散权衡，被认为是竞争者共存的关键？该项目将推进为回答这些问题而创建的数学模型的分析，并更好地理解模型动态。最后，本研究的结果将适用于保护计划和栖息地保护区设计。研究生和本科生将通过PI主办的研讨会和独立研究项目的指导进行培训。项目成果将通过同行评审的期刊、国家和国际会议讲座以及用户友好的网站传播给生态和数学界。此外，还将创建一个应用程序，从实地数据中估计关键的扩散参数，并向公众提供。本计画由数学科学部数学生物学计画与环境生物学部人口与社区生态学计画共同资助，将结合反应扩散模式、数学分析与实验分析，探讨栖地破碎化的影响，条件扩散和种间竞争对种群动态和物种共存的影响。PI将使用扩散的Lotka-Volterra竞争系统与非线性边界条件建模密度依赖移民（DDE）在补丁和景观水平和阶段结构。正在进行的研究表明，生活史特征，如一个物种是独居还是群居，可以为特定物种的DDE形式提供线索。物种的生活史的知识，再加上我们的预测，不同形式的DDE如何影响物种共存和栖息地斑块之间的连接，可以帮助确定现有的保护区是否足以物种共存。 将使用两种拟谷盗粉甲虫物种进行扩散实验，以参数化模型，并将共存和稳定性的模型预测与长期实验结果进行比较。创新性的贡献将通过提供（1）实验证据表明，种间竞争影响斑块内再分配，边界行为和DDE关系的强度和形式;（2）第一个理论框架和经验证据的影响条件扩散的种群动态和竞争物种在破碎景观共存;以及（3）具有非线性边界条件的椭圆边值问题的新颖分析。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估而被认为值得支持。

项目成果

A study of logistic growth models influenced by the exterior matrix hostility and grazing in an interior patch

外部基质敌对和内部斑块放牧影响的物流增长模型研究

• DOI: 10.14232/ejqtde.2020.1.17
• 发表时间: 2020
• 期刊: Electronic Journal of Qualitative Theory of Differential Equations
• 影响因子: 1.1
• 作者: Fonseka, Nalin;Machado, Jonathan;Shivaji, Ratnasingham
• 通讯作者: Shivaji, Ratnasingham

Frequency of Occurrence and Population-Dynamic Consequences of Different Forms of Density-Dependent Emigration

• DOI: 10.1086/708156
• 发表时间: 2020-05-01
• 期刊: AMERICAN NATURALIST
• 影响因子: 2.9
• 作者: Harman, Rachel R.;Goddard, Jerome, II;Cronin, James T.
• 通讯作者: Cronin, James T.

The diffusive Lotka–Volterra competition model in fragmented patches I: Coexistence

碎片化斑块中的扩散LotkaâVolterra竞争模型I：共存

• DOI: 10.1016/j.nonrwa.2022.103775
• 发表时间: 2023
• 期刊: Nonlinear Analysis: Real World Applications
• 作者: Acharya, A.;Bandyopadhyay, S.;Cronin, J.T.;Goddard, J.;Muthunayake, A.;Shivaji, R.
• 通讯作者: Shivaji, R.

Modeling the effects of trait-mediated dispersal on coexistence of mutualists

模拟特征介导的扩散对互利共存的影响

• DOI: 10.3934/mbe.2020399
• 发表时间: 2020
• 期刊: Mathematical Biosciences and Engineering
• 影响因子: 2.6
• 作者: T. Cronin, James;Goddard II, Jerome;Muthunayake, Amila;Shivaji, Ratnasingham
• 通讯作者: Shivaji, Ratnasingham

Ecological release and patch geometry can cause nonlinear density–area relationships

生态释放和斑块几何形状会导致非线性密度与面积关系

• DOI: 10.1016/j.jtbi.2022.111325
• 发表时间: 2023
• 期刊: Journal of Theoretical Biology
• 影响因子: 2
• 作者: Goddard, Jerome;Shivaji, Ratnasingham;Cronin, James T.
• 通讯作者: Cronin, James T.