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McGovern, Thomas H  Hunter College, CUNY.

This presentation focuses on past and present issues of environmental and socio-economic change in the Lake Mývatn region in northeast Iceland. This area, and indeed, Iceland as a whole, represents a striking case of dramatic landscape change. Since first settlement in the late ninth century, over 90% of the native forest has been lost, the productivity of the rangelands has been substantially degraded, and as much as 40% of the soil cover lost to catastrophic erosion. Whole districts that were densely settled in the tenth century have become abandoned, and in the seventeenth to early nineteenth centuries, the population was repeatedly devastated by disease, famine, and volcanic eruptions. Erosion control is a major goal of the modern Icelandic state, and the long term sustainability of agriculture in Iceland holds many lessons for other circumpolar cases. The causes of this disastrous interaction of human economy and northern ecosystems have long been debated, with different authors giving different weight to grazing pressure, volcanism, soil-nutrient depletion, climate fluctuation, and simple land management error, generally basing their arguments on one or two lines of evidence: a genuinely integrated systems science approach to this problem is only recently beginning to emerge (Arnalds et al. 1987; Friðriksson 1972; Ólafsdóttir and Guðmundsson 2002; Simpson et al., 2001, 2004; Thorsteinsson et al., 1971). Current research suggests that broad-scale simplistic arguments (stocking versus climate) in fact obscure the complexities of the actual situation at the local level, where some farm sites seem to rapidly deplete local resources, suffer catastrophic soil loss and become abandoned, while other farms a few kilometers away seem to achieve millennial-scale sustainability and show little erosion impact. In discussions of landscape sensitivity human actions have generally been regarded as external forces contributing to landscape change. However, our studies have integrated physical and social systems in an historic context to explain the basis of human actions and their consequences in sensitive landscapes. Exploration of historical common land management in Iceland through integrated historical modeling approaches has demonstrated no “tragedy of the commons” in Icelandic grazing. Common lands have tightly defined regulations, including: definition of boundaries and membership; congruent rules; conflict-resolution mechanisms; and graduated sanctions from at least AD 1200 onwards. Furthermore, sufficient biomass was available across common land areas to support the numbers of livestock indicated by historical sources. We find that the scheduling of livestock management is more likely to contribute to landscape degradation than absolute numbers in common land areas grazed during the summer months. The significance of historical grazing management in shaping long-term land sustainability or degradation has also been demonstrated by assessment of land-degradation patterns in traditional winter grazing areas, with distinct and different landscape responses to winter grazing observed (Simpson et al., 2000). Volcanic tephra layers provide tight chronological control (tephra falls occur in the area most decades, with a major local eruption in 1982) allowing the correlation of distant sites and calculation of erosion/ accumulation rates with high levels of precision (Dugmore et al., 1992). In the northern Iceland study areas considered, accelerated wind and water erosion is observed with colonization and settlement c. AD 874 through to c. AD 1477. Subsequently, in some locations, erosion rates decline through to the present day, while in other areas erosion rates continued to accelerate and create areas of arctic desert. Explanation of these research findings may lie, at least partially, in that adaptive grazing management was used where erosion rates are reduced, and, conversely, the failure to adopt sensitive grazing management regimes allowed erosion to accelerate. Our study combines integrated interdisciplinary millennium-deep investigations of long-term interactions with high temporal resolution (decadal to annual scale) of environmental and landscape changes and present-day local and scientific knowledge. The presentation will include discussion of three major research components of our study: 1). Environment, climate, and landscape, both for wider North Atlantic teleconnections, and for the local Mývatn region; 2) The people who live and work in the Mývatn region (the Human Dimensions of the study); and 3) Integration of Human/Environment Interactions from global issues to local Mývatn perspectives.

Arnalds, Ó., Aradóttir, A.L. and Thorsteinsson, I., 1987. The nature and restoration of denuded areas in Iceland. Arctic and Alpine Research, 19(4), 518-525.

Dugmore, A.J., Larsen, G., Newton, A.J.,and Sugden, D.E. (1992). Geochemical stability of fine-grained silicic tephra layers in Iceland and Scotland. Journal of Quaternary Science, 7, 173-183.

Friðriksson, S.1972. Grass and grass utilization in Iceland, Ecology 53, 785 796.

Ólafsdóttir, R. and Gudmundsson, H.J. 2002. Holocene land degradation and climate change in NE Iceland, The Holocene 12 (2):159-167.

Simpson, I.A., Dugmore, A.J., Thomson, A. and Vésteinsson, O. 2001. Crossing the thresholds: human ecology and historical patterns of landscape degradation. Catena, 42, 175-192.

Simpson, I.A., Adderley, W.P., Gudmundsson, G., Hallsdóttir, M., Sigurgeirsson, M.A. and Snaesdóttir, M. 2004. Soil limitations to agrarian land production in pre-modern Iceland. Human Ecology. (in press).

Thorsteinsson, I., Ólafsson, G. and Van Dyne, G.M., 1971. Range resources of Iceland. Journal of Range Management, 24(2), 86-93.

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