Conditionally rare taxa contribute but do not account for prokaryotic community changes in soils

Conditionally rare taxa (CRT) are thought to greatly impact microbial community turnover across many environments, but little is known about their role in soils. Here, we investigate the contribution of CRT to whole community variation over space and time in a series of geographically distinct soils dedicated to three agricultural practices of differing intensities and sampled over a full seasonal cycle. We demonstrate that soil CRT do not account for observed total community changes, but that these rare taxa can be modified by spatiotemporal filters.