Houadria Mickal, Menzel Florian
Institute of Organismic and Molecular Evolutionary Biology, University of Mainz, Mainz, Germany.
Institute of Entomology, Biology Centre of Academy of Sciences and Faculty of Science, University of South Bohemia, Branisovska, Ceske Budjovice, Czech Republic.
Oecologia. 2017 Aug;184(4):885-899. doi: 10.1007/s00442-017-3900-x. Epub 2017 Jul 26.
Biodiversity is known to increase ecosystem functioning. However, species vary in their contributions to ecosystem processes. Here, we investigated seven ecosystem functions based on the consumption of different resources in tropical ant communities. We analysed how different species influence site-level resource consumption, and determined how each species influenced performance and stability of these functions. Based on simulated extinctions, we identified 'key species' with significant functional contributions. We then investigated which traits, such as biomass, abundance, and specialisation, characterized them, and compared trait distributions across four sites to analyse differences in functional redundancy. Only few species significantly influenced ecosystem functions. Common generalist species tended to be the most important drivers of many ecosystem functions, though several specialist species also proved to be important in this study. Moreover, species-specific ecological impacts varied across sites. In addition, we found that functional redundancy varied across sites, and was highest in sites where the most common species did not simultaneously have the greatest functional impacts. Furthermore, redundancy was enhanced in sites where species were less specialised and had more even incidence distributions. Our study demonstrates that the ecological importance of a species depends on its functional traits, but also on the community context. It cannot be assessed without investigating its species-specific performance across multiple functions. Hence, to assess functional redundancy in a habitat and the potential for compensation of species loss, researchers need to study species-specific traits that concern functional performance as well as population dynamics and tolerance to environmental conditions.
众所周知，生物多样性可增强生态系统功能。然而，不同物种对生态系统过程的贡献各不相同。在此，我们基于热带蚂蚁群落对不同资源的消耗情况，研究了七种生态系统功能。我们分析了不同物种如何影响场地层面的资源消耗，并确定了每个物种如何影响这些功能的表现和稳定性。基于模拟物种灭绝，我们识别出了具有显著功能贡献的“关键物种”。然后，我们研究了哪些特征，如生物量、丰度和特化程度，能够表征这些关键物种，并比较了四个场地的特征分布，以分析功能冗余的差异。只有少数物种对生态系统功能有显著影响。常见的广食性物种往往是许多生态系统功能的最重要驱动因素，不过在本研究中，也有几种特化物种被证明很重要。此外，特定物种的生态影响因场地而异。此外，我们发现功能冗余因场地而异，在最常见物种并非同时具有最大功能影响的场地中最高。此外，在物种特化程度较低且分布更均匀的场地中，冗余性增强。我们的研究表明，一个物种的生态重要性不仅取决于其功能特征，还取决于群落背景。如果不研究其在多种功能上的特定物种表现，就无法进行评估。因此，为了评估栖息地中的功能冗余以及物种损失的补偿潜力，研究人员需要研究与功能表现、种群动态以及对环境条件的耐受性相关的特定物种特征。
