Fig 1.
(A) Overview of the Negev region showing the three archaeological sites investigated in this study. The approximate perimeter of the urban/agriculture heartland is outlined. (B) Aerial view of Shivta with location of the excavated Area M Byzantine trash mound, as well as Areas E and K where small Early Islamic middens are located. (C) Aerial view of Elusa with location of the excavated Area M1(A) Byzantine trash mound. (D) Aerial view of Nessana with location of the excavated Area A trash mound, where Byzantine trash is overlain by Early Islamic trash. Orthophoto images reprinted under a CC BY license, with permission from The Survey of Israel (gov map), 2019.
Fig 2.
Archaeological trash mound profile sections investigated in this study.
(A) The 1.5-meter-thick section excavated into the Area M Byzantine period trash mound at Shivta. The grey lens (samples 16 and 17) and gravel layer (sample 4) are distinct. (B) Early Islamic middens at Shivta Areas E and K. (C) The 1.3-meter-thick section exposed at the Elusa Area A Byzantine period trash mound showing a stratigraphic sequence of alternating light and dark layers, along with two layers comprised primarily of gravels (samples 3 and 10). (D) Sampled Byzantine layers at Nessana. (E) The Early Islamic component of the west section displays a basin-shaped feature comprised of two packages of reddish, black, and grey layers. (F) The Early Islamic component of the north section is also characterized by a similar basin-shaped feature with four packages, each comprised of reddened, blackened, and grey layers.
Fig 3.
Results of the micro-geoarchaeological analyses conducted on sediments from the Shivta middens.
(A) Profile section of the Byzantine hinterland trash mound. Phytolith, dung spherulite, and ash pseudomorph concentrations (M/g), OM content (wt. %), and mineralogy are plotted stratigraphically. Mineralogy is shown for key units. Darker layers are highlighted in grey. The 30% measurement error expected for micro-remains quantification is demarcated with red error bars. (B) Early Islamic middens. Note the lack of clear layering. Heated clays, ash derived minerals, and large amounts of dung spherulites characterize these sediments. Abbreviations: M/g = millions of micro-remains per gram of sediment; wt. % = weight percent; Cy (ua/500°C) = clay (unaltered/heat-altered at the designated temperature); Cl (g/a) = calcite (geogenic/ash); Q = quartz; G = gypsum; N = sodium nitrate; O = opal; Ap = apatite; Ar = aragonite; An = anhydrite.
Fig 4.
Results of the geoarchaeological analyses conducted on sediments from the Elusa trash mound.
Concentrations of phytoliths, dung spherulites, and ash pseudomorphs (M/g), OM (wt. %), and mineralogy are plotted stratigraphically. Darker layers are highlighted in grey. Error bars and abbreviations as in Fig 3. Note the alternating pattern of phytolith, dung spherulite, and organic matter contents corresponding with light and dark layers. Dark layers also commonly display signatures for heat altered clay and ash derived minerals. Mineralogy is shown for these layers.
Fig 5.
Results of the micro-geoarchaeological analyses conducted on sediments from the Nessana trash mound.
Concentrations of phytoliths, dung spherulites, and ash pseudomorphs (M/g), OM (wt. %), and mineralogy are plotted stratigraphically. Darker layers are highlighted in grey. Error bars and abbreviations as in Fig 3. (A) The Byzantine layers have internally consistent micro-remain characteristics. (B, C) The grey layers in these Early Islamic contexts display lower organic matter than the darker layers and mineralogical signatures for heated clay. Dung spherulite concentrations are relatively high throughout the tested sediments. Representative mineralogy is shown.
Fig 6.
Ash pseudomorph to dung spherulite ratios plotted against phytolith concentrations for trash layers containing burned refuse.
Fuel sources are inferred using this plot (after Gur-Arieh et al. 2013, 2014). The graph is sectioned into regions of dung dominated ash (lower PSRs and higher phytolith concentrations), wood dominated ash (higher PSRs and lower phytolith concentrations), and mixed dung/wood ash (PSR ranging between 1 and 5). Dung fuel refuse is present at all sites. The uppermost dark layer from Elusa (H13) and the grey lens from Shivta contain wood dominated ash. One sample from early Islamic Nessana (N20) is an outlier for the site, which likely relates to dung spherulite decomposition during high temperature burning.
Fig 7.
Boxplot comparison of dung spherulite concentrations across the Shivta, Elusa, and Nessana sediments.
The box represents the interquartile range, and the upper and lower whiskers represent the maximum and minimum values respectively. The internal solid line is the median, while the dashed line is the mean. Dashed red lines represent the mean 30% error typical of micro-remains quantification analyses. Outliers are listed by sample number (i.e., bulk sediments from Byzantine Nessana).
Table 1.
Deposit Types (DT) defined according to distinct macro and microscopic sediment characteristics and formation processes.