Rare niches and the ecological equivalence of species
Rare niches and the ecological equivalence of species
复制标题
稀有生态位和物种的生态等效性
DOI：
10.1007/s12080-015-0267-7
复制
发表时间：
2015
影响因子：
1.6
通讯作者：
A. Siepielski
中科院分区：
文献类型：
--
作者：
S. Haney;Matthew Cattivera;A. Siepielski
关于利基和中性过程在构建生物群落方面的贡献，争论仍然存在。这两个过程可能在多大程度上共同运作的时间变化，使得解决它们的作用的问题更加令人望而生畏。在这里，我们通过使用竞争对手的确定性和随机模型来研究稀有生态位的出现是如何影响物种多样性的，在这个通常是中性结构的群落中，我们对这个问题有了深入的了解。稀有的生态位是通过允许每个物种获得独特的资源来模拟的，这种资源随着时间的变化而发生。尽管确定性模型的结果是明确的(罕见的利基市场为原本中立的竞争者提供了稳定的共存)，但人口随机性使这一图景变得复杂。随机稀有生态位模型显示了参数机制，其中稀有生态位的增加实际上通过放大种群数量的方差而增加了灭绝风险。我们还使用我们的随机模型来评估当前经验方法在解决稀有生态位系统和中性系统之间的差异方面的有效性。我们发现，在许多情况下，随机变化使得生态位系统和中性系统无法区分，从而允许生态位系统伪装成中性系统。这些结果突出表明，有必要更好地了解人口随机性和环境变化如何影响物种多样性的维持。
Debate remains on the contributions of niche and neutral processes in structuring biological communities. Temporal variation in the extent to which these two processes may jointly operate makes the problem of resolving their roles even more daunting. Here, we gain insight into this problem by using deterministic and stochastic models of competitors to investigate how the occurrence of rare niches, in what is usually a neutrally structured community, affects species diversity. Rare niches are modeled by allowing each species access to unique resources, which occur with temporal variability. While results from the deterministic model are clear (rare niches provide stable coexistence to otherwise neutral competitors), demographic stochasticity complicates this picture. Stochastic rare niche models show parameter regimes where increases in rare niches actually increase extinction risk by amplifying the variance in population counts. We also use our stochastic model to evaluate the effectiveness of current empirical methods in resolving the difference between rare niche and neutral systems. We find that in many cases, stochastic variation makes niche and neutral systems indistinguishable, allowing for the possibility of niche systems to masquerade as neutral ones. These results highlight the need to better understand how demographic stochasticity and environmental variation can affect the maintenance of species diversity.