LONG-TERM DEPOSITION PATTERNS OF AIRBORNE WASTES IN THE NORTH-EAST OF ESTONIA
M. KAASIK University of Tartu, Institute of Environmental Physics 4 Tähe St., Tartu 51010 Estonia V. LIBLIK Tallinn University of Educational Sciences, Institute of Ecology, North-East Estonian Department 15 Pargi St., Jõhvi 41537 Estonia |
H. KAASIK University of Tartu, Institute of Theoretical Physics 4 Tähe St., Tartu 51010 Estonia |
The deposition loads of fly ash and sulfur have been high
in the NE Estonia since the late fifties, when the oil shale energetics, chemical and cement
industry achieved the remarkable extent. The combined effects of both pollutants have seriously
damaged sensitive ecosystems (forest on podzolic soils and bog). The main effects are related
with alkalization due to accumulation of fly ash components and the Sphagnum growth inhibition
due to sulfur load. These effects have the time scale of several years or even more. The pollution loads have been changed during recent 40 years due to launching and reconstruction of enterprises (incl. purification systems) and variations of production capacity. First representative data on air pollution deposition originate from the middle of eighties. Only model estimations could be used to quantify the deposition fluxes before that time, as well as for assessing the future scenarios. The air pollution dispersion and deposition model AEROPOL is used for this purpose. The estimations are based on air pollution emissions per production unit and climatic average dispersion conditions. The model estimations are compared with available measured values. The deposition loads for a possible development in the future are estimated. |