Evolutionary analysis of the contemporary landscape sphere of the earth and prognosis

Abstract

Recently, the dynamics of the landscape sphere over different time scales have become the focus of increased attention. The origin of the landscape sphere, monitoring of the changes which the sphere has undergone and is undergoing, and prediction of future events, have been combined into the new discipline of ‘evolutionary geography’. The structure of the landscape sphere is mainly controlled by the hydrothermal regime, in particular by solar energy input, spatial distribution of heat, and heat and moisture transport over the earth's surface. The present-day landscape sphere is characterized by belts of temperate and tropical forests in a polyzonal system. The natural course of climatic change would result in the future transformation of the landscape sphere to a cryohyperzonal system dominated by open tundra-steppes, steppes, and deserts. Anthropogenic modification of the climate, however, is likely to significantly disturb this pattern. Efforts to assess future changes are centered around determination of paleoecological regimes, both prior to and during the earlier phases of anthropogenic modification. The main process of man's impact on the zonal structure of the landscape sphere is deforestation, which will lead to an artificially-created hyperzonal system dominated by warm temperatures and open areas. If the prognosis of global warming and permafrost degradation is realized, the future of the landscape sphere must be viewed apprehensively.