Vegetation and geomorphic surfaces in the Elwha River delta, Washington, after dam removal, derived from 2016 and 2018 aerial imagery and 2007, 2014, and 2018 field surveys

Removal of two large dams from the Elwha River, Washington USA, in 2011-2014 released ~20.5 metric tons (Mt) of impounded sediment, ~5.4 Mt of which was deposited in the river delta and estuary. This dataset presents measurements of geomorphic surfaces, vegetation colonization, and plant community development in the Elwha River delta and estuary after dam removal. Geomorphic surfaces and vegetation colonization were estimated from aerial imagery of the delta and estuary in 2016 and 2018. Plant community development was quantified from field plot surveys of pioneer plant communities on new surfaces in 2014 and 2018 and of established delta and estuarine plant communities on older surfaces in 2007, 2014, and 2018. The dataset includes ortho-rectified aerial imagery for the delta and estuary: (1) 20160811_Elwha_delta and (2) 20180719_Elwha_delta. Second, it includes four polygon shapefiles of cover by geomorphic surface types and vegetation types drawn from the 2016 and 2018 aerial imagery: (3) BeachUnits_2016.shp, (4) BeachUnits_2018.shp, (5) VegUnits_2016.shp, and (6) VegUnits_2018.shp. Third, it includes three tabular data files of field plot measurements: (7) plant species richness and cover summed by functional group (woody, forb, graminoid, perennial, annual/biennial, native, introduced) in each plot each year (VegPlot_FunctGrpRichCover_2007-2014-2018.csv), (8) percent cover by plant species visually estimated in each plot each year (VegPlot_SpCover_2007-2014-2018.csv), and (9) edaphic conditions (soil depth, soil surface gravel/cobble, surface age, surface elevation) measured in each plot on new surfaces in the delta and estuary in years during and after dam removal (VegPlot_NewSurfaceEdaphic_2014-2018.csv). Fourth, it includes two point shapefiles of (10) locations of sampled field vegetation plots (VegPlot_Locations_2007-2014-2018.shp) and (11) point locations for a stratified random sample within new surface polygons in the delta and estuary in 2018 (NewSurface_StratRandSample_2018.shp); this stratified random sample was used in an analysis of surface development and dynamics based on U.S. Geological Survey annual digital elevation models of the delta and estuary in 2011-2018. Finally, the dataset includes 11 metadata files (.xml), one for each of the 11 data files.