报告题目：Precipitation governing vegetation patterns in an arid or semi-arid environment

报告人：原三领

报告时间：2023年07月03日（周一）11:00-12:00

报告地点：数学楼315会议室

报告摘要：In an arid or semi-arid environment, precipitation plays a vital role in vegetation growth. Recent researches reveal that the response of vegetation growth to precipitation has a lag effect. To explore the mechanism behind the lag phenomenon, we propose and investigate a water-vegetation model with spatiotemporal nonlocal effects. It is shown that the temporal kernel function does not affect Turing bifurcation. For better understanding the influences of lag effect and nonlocal competition on the vegetation pattern formation, we choose some special kernel functions and obtain some insightful results: (i) Time delay does not trigger the vegetation pattern formation, but can postpone the evolution of vegetation. In addition, in the absence of diffusion, time delay can induce the occurrence of stability switches, while in the presence of diffusion, spatially nonhomogeneous time-periodic solutions may emerge, but there are no stability switches; (ii) The spatial nonlocal interaction may trigger the pattern onset for small diffusion ratio of water and vegetation, and can change the number and size of isolated vegetation patches for large diffusion ratio. (iii) The interaction between time delay and spatial nonlocal interaction may induce the emergence of traveling wave patterns, so that the vegetation remains periodic in space, but is oscillating in time. These results demonstrate that precipitation can significantly affect the growth and spatial distribution of vegetation.

报告人简介：原三领，教授，博士生导师，上海理工大学应用数学学科负责人，中国数学会生物数学专业委员会副主任，国际SCI期刊Mathematical Biosciences and Engineering编委。研究方向为：微分方程与动力系统、生物数学。曾先后主持多项国家自然科学基金面上项目和上海市项目的研究工作。研究内容涉及微分方程与动力系统、种群动力学、流行病动力学、海洋生态学以及生物化学工程等诸多领域，具有多学科交叉的特点。曾多次受邀到国内和国际多所高校进行合作研究和学术交流。已在Journal of Mathematical Biology、Journal of Differential Equations、Journal of Nonlinear Sciences、Bulletin of Mathematical Biology等国内外重要学术刊物上发表SCI论文100余篇。