Amplicon sequencing of 30 UK grassland soils subjected to an in situ drought treatment with paired controls. Experiment was a hierarchical nested design with three regions (Devon, North Yorkshire, Aberdeenshire), each with five sites that had paired intensively and extensively managed farm fields, and within each field, three plots were established with paired control and drought (rain shelter) treatments. Grasslands were all grazed, and intensively managed fields tended to have lime applications, fertilizer applications, and heavier stocking densities when grazed than they’re paired extensive fields. Treatments were established in May 2016 and ended (shelters were removed) in July 2016. All plots were sampled twice: the first sampling was at “day 0”, immediately after the drought treatment, and the second sampling was at “day 60”, after a 60-day post drought recovery period. Soil samples were taken to 10 cm depth (2.5 cm diameter cores), and 3 cores were composited to yield one sample per plot per timepoint. Soils were kept cool during transport to the laboratory (maximum of 48 hours), then sieved to 4 mm and subsamples were frozen at -80°C prior to sequencing.
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