在连接的人口崩之前,太空中的恢复速度较慢
Lei Dai1, Kirill S Korolev, Jeff Gore
1Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. dailei@mit.edu
Nature
|April 12, 2013
概括
早期预警信号可以预测人口崩. 一个新的空间指标"恢复长度"显示出在扩展系统中比时间信号更大的潜力.
科学领域:
- 生态生态学 生态生态学
- 数学生物学 数学生物学
- 系统生物学 系统生物学
背景情况:
- 从临界点附近的扰动中恢复速度较慢,可能表明即将发生的灾难.
- 现有的早期预警指标依赖于时间波动模式,但需要长期数据.
- 在空间扩展系统中警告信号的有效性仍未得到充分探索.
研究的目的:
- 用空间时间波动在空间扩展的酵母菌种群中评估早期预警信号.
- 为了确定临界点的新型空间预警指标.
- 为了比较空间与时间警告信号的预测能力.
主要方法:
- 利用了空间扩展的酵母种群,表现出折叠分叉 (转折点).
- 分析了时空波动模式,以评估已知的早期预警指标.
- 引入并测量了一种新的空间指标:"回收长度".
主要成果:
- 在人口崩之前,两个已确定的基于波动的指标增加了,但由于分散,与孤立群体相比,增幅不那么明显.
- 新的指标"恢复时间"在人口崩之前显著增加.
- 恢复长度显著增加,表明恢复的空间规模越来越大.
结论:
- 空间预警信号,特别是"恢复长度",显示出预测扩展系统的临界点的前景.
- 与时间指标相比,恢复时间长度可能提供更好的警告信号,特别是当长期数据无法获得时.
- 在空间扩展的种群中分散可以抑制时间警告信号.
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