Human impacts on the tundra-taiga zone dynamics: the case of the Russian lesotundra.

The tundra-taiga zone is considered not only as a natural ecotone, but as a unique fringe zone with socioeconomic peculiarities. This holistic approach enables us to analyze several significant types of human impacts (industrial impacts and those associated with renewable resources development, including traditional reindeer herding and human settlements) and their role in the displacement of the lesotundra zone. In Russia, there is much evidence of deforestation and ecosystem degradation in different regions of the lesotundra zone and the northern taiga which borders the lesotundra zone. One indicator of this is that in the Archangelsk region and the Komi Republic, the observed current southern border of the lesotundra zone lies 40-100 km to the south of the southern boundary of the Protection Belt of Pretundra Forests, established in 1959. Human impacts also displace the northern boundary of the lesotundra zone (the boundary with the tundra zone) to the south. As a result, according to published estimations, the total area of human-made tundra and lesotundra stretching from the Kola Peninsula to Chukotka, is c. 470-500,000 km2. The increases in man-made tundra lead to negative consequences for the sociocultural sustainability of the lesotundra zone, a decrease in the quality of life (notably for permanent residents and native people and increases in mortality and depopulation. It cannot be predicted with any certainty that climate warming in the tundra-taiga zone will lead to a northward movement of the boreal forest treeline. We need also to consider the human impacts discussed in this article, which may actually lead to a southward movement of the lesotundra zone.