题目：Dynamics of a nonlocal phytoplankton competition model with crowding effects

报告人：聂华教授，MK体育

报告时间：2025年9月26日星期五，下午2：30

地点：腾讯会议：387-332-238

摘要：This study explores a nonlocal reaction-diffusion-advection system that models interactions between two competing phytoplankton species in a water column, incorporating crowding effects. We introduce a special cone $\mathbb{K}$ based on the cumulative distributions of population densities and establish a comparison principle under the order induced by $\mathbb{K}$.This results in strong monotonicity within the semiflow generated by the system.We then analyze the dynamics of the system in terms of the advection rates of the two phytoplankton species using monotone dynamical system theory.We identify critical curves that categorize competition outcomes into competitive exclusion, coexistence, and/or bistability.The position and shape of these critical curves can vary significantly depending on key parameters, such as death rates.Furthermore, we derive global results for specific scenarios using a perturbation approach.These findings highlight the crucial role of advection rates and death rates in shaping dynamics within two-species phytoplankton communities.

报告人简介：聂华，教授、博士生导师，研究方向：反应扩散方程与空间生态种群模型。现任中国数学会生物数学专业委员会委员、中国数学会计算数学分会理事。2006年于MK体育获得博士学位；入选教育部“新世纪优秀人才支持计划”和陕西省“青年科技新星”，获得陕西省杰出青年基金；多次赴美国明尼苏达大学、澳大利亚新英格兰大学、台湾清华大学合作研究与访问。已主持国家自然科学基金面上项目3项，主持完成省部级项目3项；已在“SIAM J. Appl. Math.”、“SIAM J. Math. Anal.”、“SIAM J. Appl. Dyn. Syst.”、“J. Differential Equations”、“J. Math. Biol.”、“Math. Biosci.”、“European J. Appl. Math.”、“Proc. London Math. Soc.”、“Sci. China Math.”等国内外知名刊物上发表学术论文80多篇。

题目：Dynamics of Intraguild Predation Models

报告人：舒洪英教授，广州大学

报告时间：2025年9月26日星期五，下午4：00

地点：腾讯会议：387-332-238

摘要：We incorporate a stage structure characterized by the maturation delay of intraguild (IG) prey into a three-species IG predation (IGP) model. We derive conditions for the existence and stability of nonnegative equilibria. By selecting the IG prey maturation delay as a bifurcation parameter at the positive equilibrium, we perform Hopf bifurcation analysis and obtain stability switch results. Furthermore, we conduct double Hopf bifurcation analysis using the mortality rate of immature IG prey and the maturation delay of IG prey as bifurcation parameters to further categorize the model dynamics near the double Hopf bifurcation points. It is demonstrated that our model exhibits complex dynamic behavior, such as stability switches, the coexistence of multiple stable periodic solutions, and quasi-periodic orbits. Our findings indicate that Hopf bifurcation and double Hopf bifurcation can lead to multiple types of species coexistence: Species coexist at the equilibrium or through sustained oscillations or irregular oscillations.

报告人简介：舒洪英，2010年获Mksport体育博士学位。2008年在加拿大阿尔伯塔大学留学两年，2011年至2014年先后在加拿大新不伦瑞克大学、加拿大瑞尔森大学和约克大学任AARMS博士后研究员。2014年至2018年任职同济大学特聘研究员，博士生导师。2018年至今任MK体育特聘教授，博士生导师。2016年获上海市浦江人才计划，2017年获陕西省百人计划。先后主持2项国家自然科学基金面上项目，1项青年项目，1项上海市自然科学基金项目，1项加拿大科研基金项目。主要研究微分动力系统及其在生物数学上的应用，发表SCI收录论文50篇，分别发表在J. Math. Pures Appl., SIAM Journal of Applied Mathematics, Journal of Differential Equations, Nonlinearity, Journal of Dynamics and Differential Equations, Journal of Mathematical Biology, Bulletin of Mathematical Biology 和Journal of Theoretical Biology等SCI期刊上。任美国数学学会MR评论员、欧洲数学学会zbMATH评论员。