Insular-Arc Volcanic Ecosystems as Centres of Forming the New Parts of Continental Biosphere

摘要

The empirical statistical models of the island-arc stage of continental biosphere development in the North-West Pacific have been created by the example of regional bioclimatic system and experimental test site near the active Mendeleev Volcano on theKunashir Island (the South Kuril Ridge). The causal mechanisms of the known geographical phenomenon of insular extratropical Neo-Pacific, i.e., the general descent of the boundaries of altitudinal bioclimatic zones and the southward shift of natural zones on islands compared to the neighboring continents, are discussed. The phenomenal feature of bioclimatic system at the stage of insular landscape formation is the direct subordination of phytobiota to vertical hydrothermal gradients. It forms a systemof future altitudinal zonality of the continent already within a frame-work of low-mountain island-arc landscape. It was shown that the local geomorphological conditions created the centers of origin of diverse phytocoenological and soil structures of the higher (zonal-regional) level at the initial stages of continental biosphere development.An exceptionally important backbone role of forest phytobiota in the establishment and development of young volcanic landscapes was demonstrated. The optimizing strategy program for the development of plant communities, which is aimed at the maximum biomass formation on forest island-arc landscapes, is much more marked compared to their zonal analogs on the neighboring continent. At the same time, an exceptionally high percentage of green mass in the structure of production results in the acceleration of biological cycle as a factor of stability of forest community. All the above ensures the survival of insular ecosystems of the boreal Neo-Pacific under unfavorable conditions of "cold" oceanicity.It was determined empirically that the structure and function of topogeo(eco)systems in mobile belts of the planet are the sources of evolutionary global biosphere processes and driving forces of the biosphere evolution in whole.