Snowpack changes around a nickel-copper smelter at Monchegorsk, northwestern Russia

Snow depth in industrial barrens adjacent to the nickel-copper smelter at Monchegorsk (Kola peninsula, northwestern Russia) by the end of the winter was reduced to one-third of the depth observed in weakened and healthy forests located 30-65 km from the smelter; this reduction was due to both decline (by one-half) in the amount (mass) of snow and increase in snow density. Since winter precipitation in Monchegorsk was about the same as in an unpolluted locality 56 km south-southwest of the smelter, and snowpack characteristics correlated with site-specific wind speed, the low amount of snow around the smelter is presumably due to snow movement from open windy habitats and enhanced snow evaporation during the wind transport; higher snow densities may be explained by wind-induced compaction of snow particles. Pollution affects snowpack characteristics by modifying wind regime via forest damage; in turn, decline in snow depth influence the growth form and (possibly) performance of trees that managed to survive in heavily polluted habitats. Thus, initial (partially pollutioninduced) forest disturbance, through secondary effects, may enhance further disturbance in a positive feedback fashion; therefore, possible ecological effects of pollution-related snowpack changes should be accounted for in field studies conducted along pollution gradients within the forest zone.