Temperature-Driven Regime Shifts in the Dynamics of Size-Structured Populations
Temperature-Driven Regime Shifts in the Dynamics of Size-Structured Populations
复制标题
规模结构种群动态中温度驱动的机制变化
DOI：
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复制
发表时间：
2011
影响因子：
2.9
通讯作者：
D. Claessen
中科院分区：
文献类型：
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作者：
J. Ohlberger;Éric Édeline;L. A. Vøllestad;N. Stenseth;D. Claessen
全球变暖几乎影响到所有生物群和生态系统。其中许多影响是通过温度对个体生命率的直接影响来介导的。然而，这如何从个人转化为人口水平仍然知之甚少，阻碍了全球变暖对人口结构和动态的影响的评估。在这里，我们研究了温度对种内竞争和同类相食的影响，以及大小结构鱼类种群的种群动力学后果。我们使用的生理结构的消费者资源模型，在该模型中，我们明确的消费者生命率和资源人口增长率的温度依赖性模型。我们的模型预测，尽管资源增长率较高，但温度升高会降低资源密度，反映出消费者之间更强的种内竞争。在一个临界温度下，消费者人口动态不稳定，并从一个稳定的平衡转移到竞争驱动的世代周期，由新兵占主导地位。因此，最大年龄下降，年轻和小型鱼类的比例增加。这些模型的预测支持的假设，减少平均身体大小，由于温度升高。我们的结论是，在大小结构的鱼类种群，全球变暖可能会增加竞争，有利于规模较小的类，并诱导政权的转变，不稳定的人口和社会动态。
Global warming impacts virtually all biota and ecosystems. Many of these impacts are mediated through direct effects of temperature on individual vital rates. Yet how this translates from the individual to the population level is still poorly understood, hampering the assessment of global warming impacts on population structure and dynamics. Here, we study the effects of temperature on intraspecific competition and cannibalism and the population dynamical consequences in a size-structured fish population. We use a physiologically structured consumer-resource model in which we explicitly model the temperature dependencies of the consumer vital rates and the resource population growth rate. Our model predicts that increased temperature decreases resource density despite higher resource growth rates, reflecting stronger intraspecific competition among consumers. At a critical temperature, the consumer population dynamics destabilize and shift from a stable equilibrium to competition-driven generation cycles that are dominated by recruits. As a consequence, maximum age decreases and the proportion of younger and smaller-sized fish increases. These model predictions support the hypothesis of decreasing mean body sizes due to increased temperatures. We conclude that in size-structured fish populations, global warming may increase competition, favor smaller size classes, and induce regime shifts that destabilize population and community dynamics.