Population effects of increased climate variation
Population effects of increased climate variation
复制标题
DOI：
10.1098/rspb.2005.3148
复制
发表时间：
2005-09-07
影响因子：
4.7
通讯作者：
Drake, JM
中科院分区：
文献类型：
--
作者：
Drake, JM
全球环流模型预测，许多观测结果证实，人为气候变化改变了高频气候变率。然而，人们还没有很好地了解环境变化的模式将如何影响野生动物种群动态和其他生态过程。理论预测，随着环境变化的增加，种群的长期增长率会降低，种群灭绝的机会会增加。这是因为人口增长是一个乘法过程，长期人口增长率是一段时间内增长率的几何平均数，总是小于算术平均数。然而，当非结构化种群的人口增长率与环境驱动因素非线性相关时，环境变化的增加可以增加种群的长期增长率。这表明，与气候变化不同方面相关的环境变化模式可能以不同方式影响种群动态。具体而言，降雨量的变化增加可能会导致许多动物物种的长期增长率降低，而温度的变化增加可能会导致长期增长率增加。虽然降雨的影响在理论上得到了很好的理解和数据支持，但温度的假设影响却没有。在这里，我分析了两个数据集，研究波动的温度对浮游动物的生长速度的影响。结果是一致的预测，波动的温度应该增加长期增长率和极端人口事件的频率。
Global circulation models predict and numerous observations confirm that anthropogenic climate change has altered high-frequency climate variability. However, it is not yet well understood how changing patterns of environmental variation will affect wildlife population dynamics and other ecological processes. Theory predicts that a population's long-run growth rate is diminished and the chance of population extinction is increased as environmental variation increases. This results from the fact that population growth is a multiplicative process and that long-run population growth rate is the geometric mean of growth rates over time, which is always less than the arithmetic mean. However, when population growth rates for unstructured populations are related nonlinearly to environmental drivers, increasing environmental variation can increase a population's long-run growth rate. This suggests that patterns of environmental variation associated with different aspects of climate change may affect population dynamics in different ways. Specifically, increasing variation in rainfall might result in diminished long-run growth rates for many animal species while increasing variation in temperature might result in increased long-run growth rates. While the effect of rainfall is theoretically well understood and supported by data, the hypothesized effect of temperature is not. Here, I analyse two datasets to study the effect of fluctuating temperatures on growth rates of zooplankton. Results are consistent with the prediction that fluctuating temperatures should increase long-run growth rates and the frequency of extreme demographic events.