Interspecific differences in stochastic population dynamics explains variation in Taylor's temporal power law
Interspecific differences in stochastic population dynamics explains variation in Taylor's temporal power law
复制标题
随机种群动态的种间差异解释了泰勒时间幂律的变化
DOI：
10.1111/j.1600-0706.2012.20517.x
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发表时间：
2013
期刊：
影响因子：
3.4
通讯作者：
R. Freckleton
中科院分区：
文献类型：
--
作者：
M. Linnerud;B. Sæther;V. Grøtan;S. Engen;D. Noble;R. Freckleton
在本文中，我研究了种群数量在时间和空间上的异质性，在随机种群动力学的框架内，存在一个时间泰勒幂律的平均值和方差的关系，证实了大量的英国鸟类种群。理论预测表明，环境随机性会增大均值-方差关系的斜率，而人口随机性会减小均值-方差关系的斜率，此外，该斜率还受到密度依赖强度的影响。物种比斜率主要是由生活史变异对种群间变异的影响来解释的，空间幂律依赖于尺度，但很少有研究对此进行解释。通过使用一个模型，它结合了当地的点过程和人口密度的空间协方差，方差估计作为一个功能的面积和参数表征的基本密度过程，从而产生一个非线性泰勒的空间尺度律。利用一种新的密度场估计方法，通过方差-面积关系的斜率研究了鸟类和鱼类种群的空间聚集格局。对于鸟类的行为特征的影响没有发现影响种间差异的空间聚集模式。相反，种间差异的整体丰度在英国的影响的斜坡，从而表明在区域一级的本地过程和丰度模式的变化之间的联系。对于鱼类，种间差异的空间聚集的分布有关的行为差异。因此，采样面积对空间分布的影响可以从基本的行为特征来预测。本论文的工作有助于正在进行的泰勒幂律的讨论。它介绍了框架，以帮助解释未来的研究，这是特别重要的其他宏观生态模式的背景下。
In this thesis I investigate the heterogeneity of population abundance by using the Taylor’s power law relationship of mean and variance, in time and space.Within the framework of stochastic population dynamics, the existence of a temporal Taylor’s power law were confirmed for a large number of British bird populations. Theoretical expectations predicted that environmental stochasticity would increase the slope of the mean-variance relationship while demographic stochasticity would reduce it. In addition, the slope should also be influenced by the strength of density dependence. Here, species specific slopes were mainly explained by the effect of life history variation on interspecific variation in demographic variance.It is generally acknowledged that the spatial power law depend on scale, however, few studies have accounted for this. By using a model which incorporates both the local point process and spatial covariance of population densities, the variance was estimated as a function of area and parameters characterizing the underlying density process, thus generating a non-linear Taylor’s spatial scaling law. Using a novel method to estimate the underlying density field, the spatial aggregation pattern was investigated by the slope of the variance-area relationship in populations of birds and fish. For the bird species no effect of behavioural characteristics was found to influence interspecific differences in the spatial aggregation patterns. Instead, interspecific differences in overall abundance in the UK influenced the slopes, thus indicating a link between local processes and variation of abundance patterns at a regional level. For the fish species, interspecifc differences in the spatial aggregation of the distributions were related to behavioural differences. Consequently, the effect of sampling area on the spatial distribution may be predicted from basic behavioural characteristics.The work of this thesis contributes to the ongoing discussion of Taylor’s power laws. It introduces framework to aid interpretation of future research, which is especially important in the context of other macroecologial pattern.