16S rRNA amplicon sequences from soil samples collected at Beaver Creek, Washington. 16S rRNA amplicon sequences from soil samples collected at Beaver Creek, Washington

The are Illumina MiSeq amplicon sequences from soil samples collected from 7 sites (with three replicates per site and 3 technical PCR replicates of each replicate) along a coastal watershed draining a small first order stream, Beaver Creek, in the Washington coast. The confluence of Beaver Creek and Johns River is roughly 2.5 km upstream of the Grays Harbor estuary and 14.5 km from the Pacific Ocean, and experiences variable exposure to saline waters at high tide. Two sampling transects perpendicular to the river along the up/downstream salinity gradient were established and represent a high salt exposure site close to the culvert breach location and a moderate salt exposure site upstream of the high salt exposure site. These transects represent a coastal forested wetland with brackish (semi-salty) groundwater and consisted of three terrestrial sampling points at each transect extending from the riparian zone to the beginning of the steep upslope. An additional soil sampling point ~20m uphill from the moderate salt exposure site transect served as a purely terrestrial upland endmember.