报告题目：A spatiotemporal model for the effects of toxicants on the competitive dynamics 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
报告摘要：We develop a reaction-diffusion model with negative toxicant-taxis that incorporates spatiotemporally inhomogeneous toxicant input to investigate the impact of toxicants on the competitive dynamics of two species in a polluted aquatic environment. Here the negative toxicant-taxis models the evasive movement of avoiding toxicants by species. We establish the global well-posedness of the model, analyze the existence and stability of spatially homogeneous steady states, and derive sufficient conditions for species extinction and coexistence. Through linear stability analysis, we identify sufficient conditions on model parameters that destabilize spatially homogeneous steady states under spatiotemporally uniform toxicant input. Numerical experiments reveal the influence of key toxicant-related factors (input rate, taxis intensity, and diffusivity) on competition outcomes and species distributions. Notably, strong negative toxicant-taxis can induce spatial aggregation and segregation patterns between the species and the toxicant under uniform toxicant input. Our findings suggest that toxicant-taxis may promote population persistence and coexistence, particularly when the toxicant input is not uniform in space and time and 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 University of Alberta 生物数学中心从事博士后研究工作，合作导师为 Mark Lewis 教授 (加拿大皇家科学院院士，Senior Canada Research Chair in Mathematical Biology)。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SIAM Journal on Applied Mathematics，SIAM Journal on Applied Dynamical Systems等、生物数学期刊Journal of Mathematical Biology, Bulletin of Mathematical Biology, Mathematical Biosciences等以及理论生态学期刊Theoretical Ecology, Journal of Theoretical Biology等，其中2017年和2022年发表在SIAM Journal on Applied Mathematics上的论文均被SIAM News的Associate Editor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《Mathematical Biosciences》编委。
