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在负增长的出生-死亡-扩散模型中,由短期自身相关性诱导的生存率
A B Melka1, N Dori2, Y Louzoun1,2
1Department of Mathematics, Bar-Ilan University, Ramat Gan 52900, Israel.
Physical review. E
|October 18, 2023
概括
即使是负的平均增长率,人口的生存也是可能的. 高增长率变异,特别是时间自相关性,可以防止出生,死亡和扩散过程中的灭绝.
科学领域:
- 人口动态 人口动态
- 随机过程是指随机的过程.
- 数学生物学的数学生物学
背景情况:
- 在人口模型中,灭绝-生存过渡通常发生在零平均净增长率下.
- 增长率的随机性可以影响人口持久性,但其与时间自相关性的影响不太清楚.
研究的目的:
- 研究生长率变异和时间自相关性如何影响出生,死亡和扩散过程中的灭绝-生存过渡.
- 要确定在特定的随机条件下,即使是负的平均净增长率,人口生存是否可能.
主要方法:
- 分析出生,死亡和扩散模型,使用随时间变化的随机增长率.
- 探索不同的自相关结构 (指数法和功率法) 以及它们对人口动态的影响.
- 在灭绝-生存过渡时增长率差异条件的导出.
主要成果:
- 增长率的足够大的差异可以确保人口的生存,即使是负的平均净增长率.
- 差异的这种促进生存的效果在中间时间自相关性中持续存在,无论相关性长度如何.
- 该研究确定了过渡点临界增长率变异的一个简单条件.
结论:
- 增长率的时间自相关性可以从根本上改变种群灭绝的条件.
- 在有负平均增长率的系统中,当随机差异和自相关性存在时,可以实现人口持久性.
- 这些发现挑战了传统的观点,即零平均净增长率是灭绝生存过渡的唯一决定因素.
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