Data from: Experimental demonstration of the importance of keystone communities for maintaining metacommunity biodiversity and ecosystem functioning

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.