%0 Review article
%T Heavy-metal pollution and remediation of forest soil around the Harjavalta Cu-Ni smelter, in SW Finland
%A Kiikkilä, Oili
%D 2003
%J Silva Fennica
%V 37
%N 3
%R doi:10.14214/sf.497
%U https://silvafennica.fi/article/497
%X Heavy metals and sulphur have been emitted from the Cu-Ni smelter at  Harjavalta since 1945. This article reviews the work that has been  published in scientific journals after 1975 concerning heavy metal  deposition and the effects of pollution on forest ecosystem around  Harjavalta. The pollution has had diverse effects on boreal forest  ecosystem, e.g. vegetation, nutrient cycle mediated by microbiota and  soil animals, herbivorous insects and pathogens, resistance mechanisms  of vegetation, and birds. The deposition of heavy metals has increased  up to 30 km distance from the smelter. At 8 km distance the ecosystem  began to approximate an undisturbed ecosystem where only slight changes  in the understorey vegetation were observed. At 4 km distance the  species composition of different ecosystem components (vegetation,  insects, birds, soil microbiota) had changed and the growth of trees was  retarded. At 0.5–1 km distance, where the nutrient cycling was  disturbed and only the most resistant organisms were surviving, the  ecosystem had ceased to carry out its essential functions. Remediation  through liming or mulching with organic matter, of forest soil has had  some positive effects on the ecosystem.