一类非自治的三种群捕食与被捕食系统的定性分析

摘要

This paper mainly studies a type of predator-prey sys-tem of three species with ratio-dependence, and establishes the existence of the positive periodic solution of this type of system through using coincidence degree theory.%本文主要研究一类基于比率的非自治的三种群捕食与被捕食系统，通过使用重合度理论建立这类系统的正周期解的存在性结果。