扩散对污染斑块上Logistic种群生存的影响

The Effect of Diffusion on the Permanence of Logistic Population in the Polluted Patch

本文通过建立两斑块的单种群扩散系统 ,主要研究扩散对其中受污染的斑块上种群生存的影响 .文中所考虑的是污染斑块上外界毒素的输入量存在极限值的情形 ,得到如下结论 :无扩散时 ,若此极限值超过某一定值 ,则污染斑块上的种群趋于灭绝 ;扩散存在且两斑块上种群的扩散系数满足一定的条件时 。

The effect of diffusion on the permanence of the population in a polluted patch is studied by setting up a single population diffusive system in two patches. The analysis focuses on the case that the toxicant input in the polluted patch has a limit value. It is shown that we draw the following conclusion: when there is no diffusion and the limit value exceeds a certain value, the population in the polluted patch goes extinction. However, when the diffusion exists and the diffusive coefficients of the population between the two patches satisfy some conditions, the population of the system goes either permanence or extinction.