MODELING OF TIME-DEPENDENT BIOME SHIFTS UNDER GLOBAL CLIMATE CHANGES

The study of biosphere response to climate changes due to anthropogeni c emission of greenhouse gases is a very important scientific and prac tical problem. The core of its solution -modelling and long-term forec ast of global terrestrial vegetation changes -is considered in this pa per. There are a few approaches To modelling long-term vegetation dyna mics; their principles are discussed in brief. A model approach based on bioclimatic schemes has been chosen for further considerations. A m odel based on Holdridge's bioclimatic scheme was designed for simulati on of time-dependent biome shifts. A procedure of time delays was desi gned to take into account inertia of vegetation response to climate ch ange. It was based on expert estimates of biome replacements. Computer experiments have been designed to investigate the consequences of tim e-dependent climate changes for the vegetation of Russia. The results showed the importance of the temporal factor for long-term forecasts. The obtained assessments demonstrated complex non-linear dynamics of v egetation even under the simplest climatic scenario. Further prospects of suggested model were discussed.