Spreading speed of spatio-temporal nonlinear dynamical system can sometimes be determined either by its corresponding linear system with an explicit speed formula, or by the complicated nonlinear system itself with the existence of a pushed wavefront. In this paper, the spreading speed (the minimal speed of wavefronts) for a Lotka-Volterra competition model in spatially periodic habitats is investigated. We establish new results on the linear and nonlinear selections in terms of the spatio-periodic coefficient functions. In the case of nonlinear selection, lower and upper bound estimates of th...
