Bauer Silke, Berger Uta, Hildenbrandt Hanno, Grimm Volker
UFZ Centre for Environmental Research Leipzig-Halle, Department of Ecological Modelling, Permoserstrasse 15, 04318 Leipzig, Germany.
Proc Biol Sci. 2002 Dec 7;269(1508):2443-50. doi: 10.1098/rspb.2002.2186.
Despite the general interest in nonlinear dynamics in animal populations, plant populations are supposed to show a stable equilibrium that is attributed to fundamental differences compared with animals. Some studies find more complex dynamics, but empirical studies usually are too short and most modelling studies ignore important spatial aspects of local competition and establishment. Therefore, we used a spatially explicit individual-based model of a hypothetical, non-clonal perennial to explore which mechanisms might generate complex dynamics, i.e. cycles. The model is based on the field-of-neighbourhood approach that describes local competition and establishment in a phenomenological manner. We found cyclic population dynamics for a wide spectrum of model variants, provided that mortality is determined by local competition and recruitment is virtually completely suppressed within the zone of influence of established plants. This destabilizing effect of local processes within plant populations might have wide-ranging implications for the understanding of plant community dynamics and coexistence.
尽管人们普遍对动物种群的非线性动力学感兴趣，但植物种群被认为会呈现出一种稳定的平衡状态，这归因于与动物相比存在的根本差异。一些研究发现了更复杂的动力学，但实证研究通常时间过短，而且大多数建模研究忽略了局部竞争和定居的重要空间方面。因此，我们使用了一个基于空间明确的、以个体为基础的假设非克隆多年生植物模型，来探究哪些机制可能产生复杂的动力学，即周期。该模型基于邻域场方法，以现象学方式描述局部竞争和定居。我们发现，只要死亡率由局部竞争决定，且在已定居植物的影响区内招募几乎完全受到抑制，那么对于广泛的模型变体都会出现周期性种群动态。植物种群内部局部过程的这种破坏稳定性的效应，可能对理解植物群落动态和共存具有广泛影响。
