Laboratory of Arid and Grassland Ecology under the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, PR China.
J Theor Biol. 2011 Jun 7;278(1):127-34. doi: 10.1016/j.jtbi.2011.03.003. Epub 2011 Mar 17.
The debate on the role of species differences in shaping biodiversity patterns, with its two extremes of pure niche theory and neutral theory, is still ongoing. It has been demonstrated that a slight difference in competitive ability of species severely affects the predictions of the neutral model. At the same time, neutral patterns seem to be ubiquitous. Here, we model both negative density dependence (NDD) and competitive asymmetry (CA) simultaneously. Our simulation results show that an appropriate intensity of NDD can offset the negative effect of CA (modeled as fecundity difference) on species coexistence and produce a neutral-like species abundance distribution. Therefore, our model provides a plausible mechanistic explanation of neutral-like patterns, but contrary to the neutral model, a species' relative abundance is positively related to its competitive ability in our model.
关于物种差异在塑造生物多样性模式中的作用的争论,存在着纯粹的生态位理论和中性理论这两个极端,目前仍在继续。已经证明,物种竞争能力的微小差异会严重影响中性模型的预测。同时,中性模式似乎无处不在。在这里,我们同时对负密度依赖性(NDD)和竞争不对称性(CA)进行建模。我们的模拟结果表明,适当强度的 NDD 可以抵消 CA(表现为繁殖力差异)对物种共存的负面影响,并产生类似中性的物种丰度分布。因此,我们的模型为类似中性的模式提供了一个合理的机制解释,但与中性模型相反,在我们的模型中,一个物种的相对丰度与其竞争能力呈正相关。