The Impact of Settlement on Woodland Resources in Viking Age Iceland
Nikola Trbojevic (2016) The Impact of Settlement on Woodland Resources in Viking Age Iceland. University of Iceland, Unpublished PhD thesis. 261 pp.
The settlement of Iceland in the late 9th and early 10th centuries – the landnám – is associated with a large scale deforestation which resulted in significant and long-term consequences for the island’s fragile environment. The landnám deforestation has been the focus of academic research for more than a century, but its process and reasons remain poorly understood. The size of the pre-landnám forests has not been established and it remains unclear whether the deforestation was an unavoidable effect of human colonisation, whether it was the result of a deliberate strategy or whether it was a case of mismanagement.
The aim of this dissertation is to throw light on these issues. It establishes an estimate of the extent of the pre-landnám forests and shows that even the most generous estimates for the settlers’ requirements for fuel and building material would not have made an appreciable impact on the woodlands. Rather it was clearance for pastures and home-fields which was the cause of the large scale deforestation. The deforestation process is explored through four possible scenarios of available manpower and social relations. The scenarios are processed through a series of spatially explicit agent-based models of three sample study areas: Vestur-Eyjafjallahreppur, Mývatn and Borgarfjörður. The outcomes of those models suggest that the deforestation was the result of a deliberate strategy to establish and develop an economy based on animal husbandry. This strategy was however applied without a full awareness of the potential and the fragility of the local environments. Very early on, the newly created pastures began to suffer degradation and their grazing potential declined. The decline was caused by a combination of overgrazing, the spread of grazing-tolerant vegetation, and to a lesser degree, by woodland regrowth. As a result, the initial extent of cleared pastures proved insufficient, requiring repeated re-initiation of clearance at many locations. The model outcomes also suggest that the deforestation was neither as drastic nor as rapid as it has commonly been portrayed. Although most of the deforestation had taken place already before the end of the 9th century, it was a drawn-out process which lasted throughout the 10th century and most likely continued well into the post-landnám periods.