Alkali extraction of archaeological and geological charcoal: evidence for diagenetic degradation and formation of humic acids

Ascough, Philippa; Bird, Michael I.; Francis, S.M.; Lébl, Tomáš

doi:10.1016/j.jas.2010.08.011

Cited by 84 publications

(65 citation statements)

References 55 publications

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“…Samples were examined at 7-45× magnification for visible surface contaminants, such as adhering sediment or plant roots; these were removed by gentle scraping. Samples were weighed and placed in glass test tubes in preparation for an acid-base-acid pretreatment, a procedure commonly applied to charcoal and charred plant remains before radiocarbon and stable isotope analysis (43,44) and considered appropriate for use on archaeobotanical remains (19). This three-step procedure consisted of: (i) treatment with 10 mL of 0.5 M HCl at 70°C for 30-60 min, or until any effervescing ceased, and then rinsing in distilled water three times; (ii) treatment with 10 mL of 0.1 M NaOH at 70°C for 60 min, followed by rinsing in distilled water until the solution was clear and the pH neutral, using a minimum of three rinses; (iii) treatment with 10 mL of 0.5 M HCl at 70°C for 30-60 min, followed by three rinses in distilled water and final freeze drying.…”

Section: Methodsmentioning

confidence: 99%

Crop manuring and intensive land management by Europe’s first farmers

Bogaard

Fraser

Heaton

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

504

406

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The spread of farming from western Asia to Europe had profound long-term social and ecological impacts, but identification of the specific nature of Neolithic land management practices and the dietary contribution of early crops has been problematic. Here, we present previously undescribed stable isotope determinations of charred cereals and pulses from 13 Neolithic sites across Europe (dating ca. 5900-2400 cal B.C.), which show that early farmers used livestock manure and water management to enhance crop yields. Intensive manuring inextricably linked plant cultivation and animal herding and contributed to the remarkable resilience of these combined practices across diverse climatic zones. Critically, our findings suggest that commonly applied paleodietary interpretations of human and herbivore δ 15 N values have systematically underestimated the contribution of crop-derived protein to early farmer diets.agriculture | prehistoric | husbandry | paleodiet

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Section: Methodsmentioning

confidence: 99%

Crop manuring and intensive land management by Europe’s first farmers

Bogaard

Fraser

Heaton

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

504

406

View full text Add to dashboard Cite

show abstract

“…Samples were examined at x7-45 magnification for visible surface contaminants, such as adhering sediment or plant roots; these were removed by gentle scraping. Samples were weighed and placed in glass test tubes in preparation for an acid-base-acid (ABA) pre-treatment, a procedure commonly applied to charcoal and charred plant remains prior to radiocarbon and stable isotope analysis (Ascough et al 2011;Bronk Ramsey 2008) and considered appropriate for use on archaeobotanical remains (Fraser et al in press). This three-step procedure consisted of: 1) treatment with 10ml of 0.5M hydrochloric acid (HCl) at 70°C for thirty to sixty minutes, or until any effervescing ceased, and then rinsing in distilled water three times; 2) treatment with 10ml of 0.1M sodium hydroxide (NaOH) at 70°C for sixty minutes, followed by rinsing in distilled water until the solution was clear and the pH neutral, using a minimum of three rinses; 3) treatment with 10ml of 0.5M hydrochloric acid (HCl) at 70°C for thirty to sixty minutes, followed by three rinses in distilled water and final freeze drying.…”

Section: Methodsmentioning

confidence: 99%

Integrating botanical, faunal and human stable carbon and nitrogen isotope values to reconstruct land use and palaeodiet at LBK Vaihingen an der Enz, Baden-Württemberg

et al. 2013

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15 N values of human and faunal bone collagen and of charred plant remains from cereal crops (e.g. emmer and einkorn wheat) and pulses (lentil and pea). Our examination of this Neolithic dietary 'food web' incorporates crop δ 15 N values within a linear-mixing model to examine the estimated proportions of animal and plant protein in the human diet. We interpret the stable isotope dietary model outcomes together with accompanying archaeobotanical and zooarchaeological evidence to shed light on the role of crops in land use strategies and human diet, and conclude that (manured) crops probably formed the dominant protein source.

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“…Therefore, there is considerable interest in the potential of BC as a major atmospheric carbon sink (Lal, 2008;Lehmann et al, 2006). However, it is also clear from recent research that various forms of BC may be subject to environmental alteration and degradation on shorter timescales (Schmidt and Noack, 2000;Bird et al, 1999;Kaal et al, 2007;Ascough et al, 2010a;2010b;2011). Both biotic and abiotic mechanisms are proposed for the alteration of BC in soils.…”

Section: Introductionmentioning

confidence: 99%