Fig 1.
Location, setting and key archaeology.
A UK location of the Stonehenge Environs. Map of UK derived from OS open source administrative boundary data © Crown copyright, (Boundary Line 2021). B Eastern section of the Stonehenge World Heritage Site with key archaeological sites. Basemap 1m Lidar DTM topographic gradient over Hillshade Model (All Lidar basemaps derived from open source UK environmental agency data © Crown copyright, Environmental Agency 2017). C Location of the Blick Mead Site on the edge of the Wiltshire Avon floodplain with archaeological trenches and positions of sediment cores and transect. Basemap 1m Lidar DTM topographic gradient (SU14SW; SU14SE) over Hillshade Model (Environment Agency 2017). D Position of in-situ auroch hoofprints within the Mesolithic alluvium (Photo D. Jacques). E Evidence of butchery cut marks on auroch faunal remains (Reprinted from [2] under a CC BY license, with permission from D. Jacques, original copyright 2018).
Fig 2.
A Reconstructed sediment transect model across the floodplain of the Wilshire Avon between Blick Mead and the present river (see Fig 1). Transect shows extent of basal reworked Pleistocene gravelly chalk, fine grained alluvial deposits, peat deposits, extent of floodplain edge palaeochannel and buried soils associated with 18th and 19th century landscaping of Amesbury Abbey and construction of A303 road in the 1960s. B Detailed section drawing of fluvial-terrestrial interface between floodplain and Middle Bronze Age to late medieval lynchet. Section details the extent of basal reworked Pleistocene gravelly chalk, Mesolithic alluvium (containing auroch hoofprints), buried soil, stone surface as well as locations of sampling points in sondage 31, position of OSL and C14 dates (Photos S. Hudson).
Fig 3.
Micromorphological analysis of sediment contexts 328, 330 and 334 in the analysed sequence.
Photos of each slide are shown alongside images of general fabric and microstructure characteristics alongside key organic and inorganic features and inclusions within the sediment. (All images are in plane polarised light at 10x magnification).
Fig 4.
The combined lithostratigraphic and environmental data.
A Selected lithostratigraphic data defining the main archaeological contexts and their associated dates. Shown alongside the full plant sedaDNA assemblage displayed as a histogram of the number of PCR replicates and taxa appeared in from 1–8 as well as a composite of total read percentages. The landscape summary determined from the plant sedaDNA evidence is as follows. 1- Willow woodland within floodplain. 2- More open local landscape with willow in floodplain alongside elm and increased shrubs on terrace edge. 3- Open local landscape with slight decrease in wood/shrub taxa, increases in wetland forbs and first appearance of sedge taxa. 4- Continued open local landscape with increased woodland and graminoid diversity, alongside increasing dryland forb community. 5- Continued open local landscape with clear increases in wet and dry woodland, graminoid and forb diversity. B Pollen assemblage taken from the Mesolithic layers of Trench 19 (see text). C Fungal and algal spore assemblage from the same samples.
Fig 5.
A Timeline of the Stonehenge landscape, including radiocarbon dates from Blick Mead and other significant SWHS archaeological sites. B A representation of the development of vegetation history at Blick Mead based on the palaeoenvironmental data.