报告题目：Aspatiotemporal model for the effects of toxicants on the competitivedynamics of aquatic species

报 告 人：黄启华 教授

报告时间：2025年5月13日（星期二）上午10:00-11:00

报告地点：第四教学楼103教室

报告摘要：Wedevelop a reaction-diffusion model with negative toxicant-taxis thatincorporates spatiotemporally inhomogeneous toxicant input toinvestigate the impact of toxicants on the competitive dynamics oftwo species in a polluted aquatic environment. Here the negativetoxicant-taxis models the evasive movement of avoiding toxicants byspecies. We establish the global well-posedness of the model, analyzethe existence and stability of spatially homogeneous steady states,and derive sufficient conditions for species extinction andcoexistence. Through linear stability analysis, we identifysufficient conditions on model parameters that destabilize spatiallyhomogeneous steady states under spatiotemporally uniform toxicantinput. Numerical experiments reveal the influence of keytoxicant-related factors (input rate, taxis intensity, anddiffusivity) on competition outcomes and species distributions.Notably, strong negative toxicant-taxis can induce spatialaggregation and segregation patterns between the species and thetoxicant under uniform toxicant input. Our findings suggest thattoxicant-taxis may promote population persistence and coexistence,particularly when the toxicant input is not uniform in space and timeand the toxicant does not diffuse fast (i.e. weak diffusivity).However, strong toxicant diffusion can diminish the impact of taxis,adversely affecting population persistence and species coexistence.

报告人简介:黄启华，教授，博士研究生导师。2011年8月至2016年6月在加拿大Universityof Alberta 生物数学中心从事博士后研究工作，合作导师为MarkLewis 教授 (加拿大皇家科学院院士，SeniorCanada Research Chair in MathematicalBiology)。2016年6月通过西南大学“聚贤工程”人才引进计划被特别评聘为教授，并于2016年9月到西南大学数学与统计学院工作。主要研究方向为生物数学、偏微分方程和数值分析。科研成果主要发表在应用数学期刊SIAMJournal on Applied Mathematics，SIAMJournal on Applied Dynamical Systems等、生物数学期刊Journalof Mathematical Biology, Bulletin of Mathematical Biology,Mathematical Biosciences等以及理论生态学期刊TheoreticalEcology, Journal of Theoretical Biology等，其中2017年和2022年发表在SIAMJournal on Applied Mathematics上的论文均被SIAMNews的AssociateEditor专门撰文在美国工业与应用数学学会的官方网站上进行了报道。先后主持国家自然科学基金面上项目两项、重庆市留学人员回国创新支持计划重点项目一项。现任国际生物数学期刊《MathematicalBiosciences》编委。