Environmental filtering vs. resource-based niche partitioning in diverse soil animal assemblages
Environmental filtering vs. resource-based niche partitioning in diverse soil animal assemblages
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DOI：
10.1016/j.soilbio.2015.03.005
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发表时间：
2015-06
影响因子：
9.7
通讯作者：
Stefanie Maaß;M. Maraun;S. Scheu;M. Rillig;T. Caruso
中科院分区：
文献类型：
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作者：
Stefanie Maaß;M. Maraun;S. Scheu;M. Rillig;T. Caruso
陆地无脊椎动物构成了所描述的动物多样性的大部分，而土壤是这种多样性的主要储存库。在理解支持生物多样性的过程的经典尝试中，生态学家目前正在寻求阐明环境过滤和资源竞争在生态位划分过程中的不同作用：这些过程原则上是不同的，尽管它们可能同时作用，在多个空间和时间尺度上相互作用，并且在土壤群落的研究中经常被混淆。我们使用基于稳定同位素和性状分析的新颖方法组合来解决空间尺度上不同甲螨组合中的这些过程，原则上资源竞争可能是主要驱动因素。我们还使用了基于 beta 多样性的一般中性模型的零模型方法。群落变化的很大一部分可以用有机碳、氮和土壤结构分布的线性和周期性空间结构来解释：物种沿着环境、空间结构梯度清晰地排列。然而，与竞争相关的性状差异并没有映射到沿着环境梯度分隔物种的距离，并且中性模型提供了令人满意的β多样性模式的近似值。这些结果代表了第一个强有力的证据，表明在非常多样化的土壤节肢动物组合中，基于资源的生态位划分发挥着次要作用，而环境过滤仍然是物种分布的基本驱动因素。
Terrestrial invertebrates constitute most of described animal biodiversity and soil is a major reservoir of this diversity. In the classical attempt to understand the processes supporting biodiversity, ecologists are currently seeking to unravel the differential roles of environmental filtering and competition for resources in niche partitioning processes: these processes are in principle distinct although they may act simultaneously, interact at multiple spatial and temporal scales, and are often confounded in studies of soil communities. We used a novel combination of methods based on stable isotopes and trait analysis to resolve these processes in diverse oribatid mite assemblages at spatial scales at which competition for resources could in principle be a major driver. We also used a null model approach based on a general neutral model of beta diversity. A large and significant fraction of community variation was explainable in terms of linear and periodic spatial structures in the distribution of organic C, N and soil structure: species were clearly arranged along an environmental, spatially structured gradient. However, competition related trait differences did not map onto the distances separating species along the environmental gradient and neutral models provided a satisfying approximation of beta diversity patterns. The results represent the first robust evidence that in very diverse soil arthropod assemblages resource-based niche partitioning plays a minor role while environmental filtering remains a fundamental driver of species distribution.