A priority conservation concern in boreal regions today is pristine (primeval) forests. They are rapidly shrinking and getting fragmented due to large-scope commercial timber harvesting. Although logging volumes have dropped sharply since the 1990s, large pristine forest expanses have survived only in the least accessible areas (peri-Urals and the pre-forest-tundra of the Arkhangelsk Region and Komi Republic, Murmansk Region and northern Republic of Karelia). They are the models of primeval taiga, the core areas and dispersal centres for native fauna and flora, the refugia for the gene pool of major forest species, etc. Their biotic, recreational and environment-shaping resources are of pan-European value, given that no such unique natural objects are to be found elsewhere in Europe west of the Russian-Finnish border up to Norwegian fjords. Only small fragments of pristine forests still persist in Swedish low-mountain regions and pre-forest-tundra parts of Finland. They, too, have been repeatedly disturbed by selective cuttings in the past, significantly affecting their structure.
It has by now been proved and demonstrated that primeval (pristine) taiga was a mosaic of forest communities at a variety of secondary succession seres with a wide range of combinations: 1) in pine forests – from even-aged to various uneven-aged plant groupings in sites of different size with different scope of fire damage (up to two fires in a century); 2) in spruce forests – from even-aged to all-aged spruce climax communities with a roughly 500-1000-year development cycle (until the next total-damage fire in abnormally dry years). Some currently-held ideas of pristine forests as ‘relatively undisturbed’ communities only at the final stages of a succession (with many old trees, dead standing and dead fallen trees, etc.) are thus disproved. Spontaneous development of pristine forests could also take the course of occasional formation of wind-thrown gaps of varying size (from several square metres to several thousands hectares). This process is quite typical of spruce forest landscapes. Pristine forests in protected areas can only be preserved if the ‘natural disturbance’ mode of their dynamics is maintained – under periodic fire (lightning-caused) and wind-throw impacts.
Gromtsev, Andrey Pristine forests in the European part of the Russian boreal zone and their spontaneous dynamics