主讲人：史峻平 美国威廉玛丽学院(College of William & Mary)教授

时间：2022年4月2日9：00

地点：腾讯会议 478 127 447

举办单位：数理学院

主讲人介绍：史峻平， 美国威廉玛丽学院(College of William & Mary)数学系主任, 教授。1990-93年南开大学学习，1998年毕业于美国杨百翰大学，获博士学位。主要研究方向为偏微分方程，动力系统，分歧理论，非线性泛函分析，生物数学。在偏微分方程，分歧理论方面的研究工作受到国际上广泛重视。在生物数学方向包括种群模型，生物化学反应，形态生成，生态系统稳定性等方面都有研究。曾任哈尔滨师范大学龙江学者讲座教授，山西大学百人计划讲座教授，主持参加美国国家科学基金会基金项目多项，主持组织国际学术会议20多次，在国际学术会议做大会报告/邀请报告100余次。担任多个国际知名SCI刊物编委，为100多种数学、物理、生物刊物审稿人。发表学术论文180余篇，被引用7000余次。

内容介绍：Biodegradation is a pivotal natural process for elemental recycling and preservation of an ecosystem. Mechanistic modeling of biodegradation has to keep track of chemical elements via stoichiometric theory, under which we propose and analyze a spatial movement model in the absence or presence of bacterivorous grazing. Sensitivity analysis shows that the organic matter degradation rate is most sensitive to the grazer's death rate when the grazer is present and most sensitive to the bacterial death rate when the grazer is absent. Therefore, these two death rates are chosen as the primary parameters in the conditions of most mathematical theorems. The existence, stability and persistence of solutions are proven by applying linear stability analysis, local and global bifurcation theory, and the abstract persistence theory. Through numerical simulations, we obtain the transient and asymptotic dynamics and explore the effects of all parameters on the organic matter decomposition. Grazers either facilitate biodegradation or has no impact on biodegradation, which resolves the “decomposition-facilitation paradox” in the spatial context. This is a joint work with Xiaoyuan Chang and Hao Wang.