On the relation between temporal variability and persistence time in animal populations
On the relation between temporal variability and persistence time in animal populations
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DOI：
10.1046/j.1365-2656.2003.00767.x
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发表时间：
2003-11-01
影响因子：
4.8
通讯作者：
Halley, J
中科院分区：
文献类型：
--
作者：
Inchausti, P;Halley, J
1.研究了大量长期时间序列的时间变异性、光谱红度与种群持续性之间的关系。尽管直觉和理论都表明，种群丰度的变异性越大，灭绝的可能性就越大，但之前对这一观点的经验支持并不是决定性的。可能的原因是长期数据的缺乏和对时间变异性的充分描述的困难，这两个问题在本文中得到了明确的解决。2.我们检验了种群变异性和准灭绝时间(以观察到种群丰度下降90%所需的时间)之间的关系，这些数据包括123个物种的554个种群，调查了30多年。考虑了与准灭绝时间有关的时间变异性的两个方面：基准值(在固定的30年时间尺度上的变异系数)和种群变异性随时间增加的速度的量度(频谱指数)。结果表明，具有较高时间变异性和较红动态的种群准灭绝时间较短。比较了不同类群、营养水平、栖息地类型(水生和陆地)和体型的持续时间与种群变异性的关系，并与理论预期进行了比较。
1. The relationship between temporal variability, spectral redness and population persistence for a large number of long-term time series was investigated. Although both intuition and theory suggest that more variability in population abundance would mean greater probability of extinction, previous empirical support for this view has not been conclusive. Possible reasons are the shortage of long-term data and the difficulties of adequately characterizing temporal variability, two issues that are explicitly addressed in this paper.2.We examined the relationship between population variability and quasi-extinction time (measured as the time required to observe a 90% decline of population abundance) for a large set of data comprising 554 populations for 123 species that were censused for more than 30 years. Two aspects of temporal variability were considered in relation with the quasi-extinction time: a baseline value (coefficient of variation over a fixed, 30-year, time scale), and a measure of the rate of increase of the population variability over time (spectral exponent).3. The results show that the quasi-extinction time was shorter for populations having higher temporal variability and redder dynamics. The relation between persistence time and population variability was compared for different taxa, trophic levels, habitat type (aquatic and terrestrial) and body sizes and compared with theoretical expectations.