Application of Micromorphology to Study Manuring Practices: A Case Study from Bronze Age in Cornwall, UK

Abstract

The arable soils from Bronze Age settlement of Gwithian in Cornwall (UK) were analysed using micromorphology to recognise manuring practices over time. The analysis was conducted to determine whether the Gwithian farmers used fertilizers during Bronze Age? If they have used fertilizers, the aim of this research is also to identify which material were used. Moreover, it also aims to investigate if the sandy horizons at Gwithian (context 602 in layer 4) were stabilised by adding the midden material. Lastly, the research also describes if the context 606 was used for agricultural activity or was it a neglected area? The results of this study identify five phases of occupations where manures were used. The occurrence of rubified fine mineral, ash particles, decomposed wood, charred wood fragment with original tissue structure, shells and identifications of phytoliths from phase I and phase II of Early Bronze Age (c 1800 Cal BC) suggest that this material derived from manure heap, indicating accumulation of household waste dominated by fire residues. The occurrence of phytoliths indicates to herbivore dung component.The identifications of planar voids and the sandy grain aggregates surrounded by dusty clay coatings may indicate to practice of tillage and ploughing activities during these phases. The Early/Middle Bronze Age (phase III -context 606=6) is characterised by wind-blown sandy horizons and anthropogenic evidence were not identified from the field evidence [1]. Thin section analysis also did not show any traces of wood, burnt wood, and the pottery. However, soil aggregates surrounded by fine material may indicate that arable soils were raised by manuring practice. Moreover, few traces of yellowish porous material are also identified, which is interpreted as bone. The phase IV is ascribed to Middle Bronze Age (c 1500-1200 cal. BC). The results from this phase demonstrate that arable soils are characterised by blown sands, shells, ashes from hearth, and bones. The findings of bones, decomposed wood, charred wood, ashes from grasses and woods, rubified iron nodules, burnt carbonate, bones and evidence of animal dung demonstrate that farmers brought midden material to sandy horizons (602 =4) of this site. They used midden material not only to stabilise them, but also for increasing the fertility of soils. The Middle/Late Bronze Age (c 1300-900 cal. BC) is assigned to phase V of this site. The results of this analysis show that the midden material was continuously used as fertilizers during this phase. The noteworthy amount of burnt material (e.g. burnt wood, burnt carbonates, rubified iron nodule, few ashes) demonstrate that burning practice was common, and agricultural soils were raised by ashes. This study indicate that Bronze Age farmers have used fertilizers to increase the agricultural production.

Environment, Archaeology and Landscape: Papers in honour of Professor Martin Bell

“…Ard marks were exposed in the 2005 trench (Nowakowski 2009: 119) and cereal seeds, including Hordeum sp., were identified within the plough soils (Straker 2007;Straker & Walker 2018) but there is insufficient evidence to say whether cereals were grown on this site. Micromorphology analysis on samples obtained from the same trench suggests that household waste and animal dung was used as fertiliser at this time (Dev 2018), although animal bones dating to this period were not found within the trench (Hammon 2007). Enrichment of the fields would probably have been necessary to yield adequate crops on the blown sand.…”

“…Another period (Phase 4) of relative decline followed, with an increase in blown sand, but the lack of dating makes it difficult to determine how long this lasted. Some farming continued, with midden material used to enrich the sandy soils (Dev 2018). This period of decline probably allowed some regeneration of woodland or scrub, indicated by the mollusc assemblage from the 2005 excavation (Davies 2007).…”

“…Stone walls were constructed to enclose fields, and ard and spade marks provide evidence of arable farming (Fowler 1983: 150;Megaw et al 1960-61). Domestic midden material was used for manuring (Dev 2018) in addition to the use of seaweed to enrich the soils.…”

Europe’s Early Land Allotment: Questions of Time, Scale and Stewardship

“…New studies of manuring (e.g. Lauer et al 2014;Nielsen and Kristiansen 2014;Dev 2018;Nielsen et al 2019) target the composition and intensity of manuring on the prehistoric field systems. Unfortunately, for proxies such as coprostenoles, stable bile acids and coprophilous spore bodies, it remains difficult to argue whether they entered the fields 'on the hoof' as droppings or as part of a manure-mixture prepared in settlements.…”

Аналитические Исследования Лаборатории Естественнонаучных Методов. Вып. 5

“…Широкомасштабные и планомерные почвенно-археологические исследования ресурсных зон поселений проводятся сравнительно нечасто (см., например: Bakels, 2018), а применение при их изучении археоботанического анализа минимально, что, вероятно, обусловлено как отсутствием интереса специалистов-естественников к этим необычным археологическим памятникам, так и неразработанностью методического подхода. Редкие работы в данном направлении сфокусированы на изучении древесного угля и пыльцы (Rösch et al, 2014;Arnoldussen, van der Linden, 2017), а также почвенной микроморфологии, что в том числе позволяет обнаружить обугленные и растительные остатки (Dev, 2018). Карбонизированные зерна культурных злаков, семена и плоды сорных и древесных растений, происходящие из горизонтов древних пашен, периодически исследуются археоботаниками начиная с 1960-х гг.…”