School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA.
Oecologia. 2020 Jun;193(2):437-447. doi: 10.1007/s00442-020-04693-x. Epub 2020 Jun 16.
As local communities within a metacommunity may differ considerably in their contributions to biodiversity and ecosystem functioning, it has been suggested that conservation priority should be given to disproportionately important local communities (i.e., keystone communities). However, we know little about what characterizes a keystone community. Using laboratory protist microcosms as the model system, we examined how the environmental uniqueness and location of a local community affect its contributions to the metacommunities. We found that the removal of local communities with unique environmental conditions, which supported endemic species, reduced regional-scale diversity, qualifying them as regional-scale keystone communities. In addition, the local communities possessing unique environmental conditions had greater impacts on ecosystem functions, including biovolume production and particulate organic matter decomposition. We also found that keystone communities for biovolume production were not keystone for organic matter decomposition, and vice versa. Our study, therefore, demonstrates the important role of keystone communities in maintaining biodiversity and functioning of metacommunities.
由于在生物多样性和生态系统功能方面，一个超社区内的局部社区可能会有很大的差异，因此有人建议，应优先保护对生物多样性和生态系统功能具有不成比例重要性的局部社区（即关键社区）。然而，我们对关键社区的特征知之甚少。本研究使用实验室原生动物微宇宙作为模型系统，研究了局部社区的环境独特性和位置如何影响其对超社区的贡献。我们发现，去除具有支持特有物种的独特环境条件的局部社区会降低区域尺度的多样性，使它们成为区域尺度的关键社区。此外，具有独特环境条件的局部社区对生态系统功能（包括生物量生产和颗粒有机物质分解）有更大的影响。我们还发现，在生物量生产方面的关键社区不是在有机物质分解方面的关键社区，反之亦然。因此，我们的研究表明，关键社区在维持生物多样性和超社区功能方面发挥着重要作用。
