GROUND-LIVING ARTHROPODS ALONG POLLUTION GRADIENT IN BOREAL PINE FOREST

We studied the occurrence of arthropods in a polluted pine forest at H arjavalta, southwestern Finland. Significantly fewer beetles (Coleopte ra) were trapped near (0.5 km) a smelter and fertilizer factory than a t sites further away (3, 5, 9 km). No differences in total numbers (in ds./trap) along the distance (pollution) gradient were found for spide rs (Araneae), ants (Hymenoptera: Formicidae) or bugs (Heteroptera). Ma rked differences were observed in diversity and species composition of the studied groups between the most polluted site (0.5 km) and the ot her sites (3, 5, 9 km). There were permanent arthropod populations (e. g. ants and wolf spiders) living at the most polluted site. Difference s in ground-living fauna were explained by changes in ground vegetatio n due to pollution. The contents of Cu, Fe, Ni and Cr in ants and wolf spiders were clearly highest near the pollution source; those of Cd, Zn and Al were high at all sites.