The current paper is devoted to the study of the spreading speeds of two species competition diffusion-advection systems in time almost periodic and space periodic media. We first show that there is a finite spreading speed interval for such diffusion-advection systems. The principal Lyapunov exponent and the principal Floquent bundle theory have been applied to study the spreading speed of time almost periodic and space periodic systems. Under some sufficient conditions, we prove that the spreading speed interval of such systems in any direction is a singleton in the partially spatially homogeneous case and the general case, respectively.

中文翻译：

---

时间周期和空间周期媒体中两种群竞争系统的传播速度。

本文主要研究两种物种竞争扩散对流系统在时间周期和空间周期介质中的传播速度。我们首先表明，这种扩散对流系统存在一个有限的传播速度区间。主要的李雅普诺夫指数和主要的Floquent束理论已被用于研究时间几乎周期周期和空间周期系统的扩展速度。在某些充分条件下，我们证明了在局部空间均匀情况和一般情况下，此类系统在任何方向上的扩展速度间隔分别为单例。