Direct Impacts

In general, the direct mechanical disturbance of Arctic terrain, including vegetation, soil, and the underlying permafrost layer, often leads to erosion. Unchecked, severe erosion can progress to eventually degrade entire landscapes. Among the aforementioned three components, vegetation has special importance, not only as the basic link to the upper trophic levels of an ecosystem but also in terms of its controls over permafrost and ground-ice maintenance in tundra substrates. In addition, the regeneration of an ecosystem after disturbance is dependent upon revegetation, which is the essential first step of ecosystem recovery. Vegetation cover, therefore, is one of the best criteria to assess overall ecosystem status in the wake of previous environmental degradation.

Anthropogenic impacts are complex in that various human activities can influence ecosystems simultaneously and cumulatively, and can have both immediate catastrophic and long-term effects. Sometimes, in practice, it is difficult to distinguish between direct and indirect impacts and scientists may use different methods for classifying disturbances. For example, Russian authors distinguish three main classes of disturbed areas: "ochagovyi" (local), "lineinyi" (linear), and "fonovyi" (spatial). The most striking example of the first type includes sites surrounding petroleum boreholes (drill sites). Transport corridors appearing in connection with road and pipeline construction constitute linear disturbances. Large territories affected by air pollution are examples of spatial disturbances.

The Russian scientist Olga Sumina has characterized the main types of environmental problems in the Russian Arctic, from west to east. On the Kola Peninsula, the reaction of vegetation to chemical contamination is important due to the strong air pollution effects produced by smelter complexes there. In the Komi Republic, investigations of vegetation impacts associated with oil-field development, pipeline construction and use, and coal mining are most prominent. In northwest Siberia, much research has been undertaken in connection with exploration and exploitation of the richest oil-gas fields of northern Russia. On Taymyr Peninsula, the key topic of research is the effect of contamination from the Noril'sk industrial complex, which emits heavy metals and other toxic agents directly to the local and regional environments. In Yakutia, industrial development is primarily connected with opencast mining, which leads to the development of large quarries (see below) and tailing dumps. A specific question for Yakutia is the study of vegetation dynamics at the bottom of its many artificially drained lakes. In Chukotka, industrial disturbances are connected with the development of mineral deposits and are represented by quarries, tailing dumps, roads, and the chemical influences of refining mills.

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