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Can a population survive in a shifting environment using non-local dispersion?
Nonlinear Analysis ( IF 1.3 ) Pub Date : 2021-06-04 , DOI: 10.1016/j.na.2021.112416
Jérôme Coville

In this article, we analyse the non-local model: tU(t,x)=JU(t,x)U(t,x)+f(xct,U(t,x))fort>0, and xR, where J is a positive continuous dispersal kernel and f(x,s) is a heterogeneous KPP type non-linearity describing the growth rate of the population. The ecological niche of the population is assumed to be bounded (i.e. outside a compact set, the environment is assumed to be lethal for the population) and shifted through time at a constant speed c. For compactly supported dispersal kernels J, assuming that for c=0 the population survive, we prove that there exist critical speeds c,± and c,± such that for all c,<c<c,+ then the population will survive and will perish when cc,+ or cc,. To derive these results we first obtain an optimal persistence criteria depending of the speed c for non local problem with a drift term. Namely, we prove that for a positive speed c the population persists if and only if the generalised principal eigenvalue λp of the linear problem cDx[φ]+Jφφ+sf(x,0)φ+λpφ=0inR, is negative. λp is a spectral quantity that we defined in the spirit of the generalised first eigenvalue of an elliptic operator. The speeds c,± and c,± are then obtained through a fine analysis of the properties of λp with respect to c. In particular, we establish its continuity with respect to the speed c. In addition, for any continuous bounded non-negative initial data, we establish the long time behaviour of the solution U(t,x). In the specific situation, sf(x,0)>1 and J symmetric we also investigate the behaviour of the critical speeds c and c with respect to the tail of the kernel J. We show in particular that even for very fat tailed kernel these two critical speeds exist.



中文翻译:

人口能否在使用非本地分散的不断变化的环境中生存?

在本文中,我们分析了非本地模型: (,X)=J(,X)-(,X)+F(X-C,(,X))为了>0, 和 X电阻, 在哪里 J 是一个正的连续扩散核,并且 F(X,)是描述人口增长率的异质 KPP 类型非线性。假设人口的生态位是有界的(即在一个紧凑集之外,假设环境对人口是致命的)并以恒定速度随时间移动C. 对于紧凑支持的分散内核J,假设对于 C=0 人口生存,我们证明存在临界速度 C,±C,± 以至于对于所有人 -C,-<C<C,+ 那么人口将生存并在什么时候灭亡 CC,+ 或者 C-C,-. 为了得出这些结果,我们首先根据速度获得最佳持久性标准C对于具有漂移项的非局部问题。即,我们证明对于正速度C 种群持续存在当且仅当广义主特征值 λ 线性问题 CDX[φ]+Jφ-φ+F(X,0)φ+λφ=0电阻, 是否定的。 λ是我们根据椭圆算子的广义第一特征值的精神定义的谱量。速度C,±C,± 然后通过对属性的精细分析获得 λ 关于 C. 特别地,我们建立了它在速度方面的连续性C. 此外,对于任何连续有界非负初始数据,我们建立解决方案的长时间行为(,X). 在特定情况下,F(X,0)>1J 对称我们还研究了临界速度的行为 CC 关于内核的尾部 J. 我们特别表明,即使对于尾非常胖的内核,这两个临界速度也存在。

更新日期:2021-06-05
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