Today, I am going to discuss what insights researchers have made into the movements and practises of past European societies and their impact on the surrounding landscape through peat analysis. Methods mentioned in the previous post; Radiocarbon dating, Palynology and dateable archaeological artefacts, have all been employed in the studies discussed below, to provide a window into our past Landscapes.
Moore and Chater (1969) analysed the Pollen record of a number of scattered study sites across Mid-Wales’s upland blanket peats and some even near known positions of archaeological interest. They broke the record down into periods A-F and were able to note particular trends in pollen spore concentration which allowed them to infer land management practises.
The onset of the anthropogenic signal occurs in period A with a distinct fall in Elm pollen, a trend seen across European sites and known to be indicative of human occupation and a pastoral form of economy typical of the Neolithic era. Change to the majority of the region however, was small; the foothills and valleys of the region continued to bear a covering of Oak-Alder woodland with a Hazel understorey.
Huang (2002) studied Peatlands within the Connemara Uplands, Western Ireland. The study states that Human deforestation during the Neolithic caused a perturbation of systems over their Hydrological Balance; resulting in a shift from wooded to bog habitat.
Comparison of the period of supposed deforestation with lake sediment records of the same time, displays a spike in the alga; chara, which grows in calcareous conditions. This normally suggests an increase in catchment disturbance, which would support the theory of deforestation, and disturbance of the upland soils through farming. The major expansion of blanket bog from 4ka BP is therefore a consequence in part to an increase in agricultural activity beginning in the Bronze Age.
Further afield Barbier and Visset (1997) have studied the stratigraphy of the Logne Bog, located in the Amorican Massif, Western France. Here they have found evidence of the first impacts of the early Gallo-Roman Empire which caused a sharp rise in cereal and *ruderal pollen as agriculture expanded and diversified.
In Wales, Moore and Chater (1969) used a dateable Roman Road at Blaen-yr-Esgair to provide a historical discontinuity from which to infer the impact of the Roman occupation on vegetation. The peat that formed above the road contained considerably less tree pollen to that below suggesting significant forest clearances in the intervening period.
Finally a similar peak in cereal and ruderal pollen is identifiable in the later period E of the Moore and chater (1969) analysis. By correlating historical documented records to the peak concentration in the stratigraphy it can be attributed to the cultivation of cereals within the uplands of Mid Wales during the Napoleonic Wars, when grain prices were high and the climate suitable.
So there we have it, a very brief snap shot into the applications of this fascinating area of research. As a tool for archaeologists it can be invaluable to understanding human populations resigned to pre-history, but equally it has been essential to understanding previous temporal and spatial distributions of vegetation assemblages in relation to climate and equally can be invaluable for conservation initiatives. In conclusion Peatlands should never be taken out of the context of their surrounding landscape as by holding the two in relation to one another, researchers can understand changes in both with relation to climate an human forcing’s.
Definition:
Ruderal: Plant species that typically first colonise disturbed land.
References:
Barbier, D., L, Visset., 1997. Logne, a peat bog of European ecological interest in the Massif Armorican, Western France: bog development, vegetation and land-use history. Vegetation History and Archaeobotany, 6, 69-77.
Huang, C.C., 2002. Holocene landscape development and human impact in the Connemara Uplands, Western Ireland. Journal of Biogeography, 29, 153-165.
Moore, P.D., E.H, Chater., 1969. The changing Vegetation of West-Central Wales in the light of Human History. Journal of Ecology, 57, 361-379.
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