On the chemical water quality in Høylandet, a reference area for acidification research

Abstract

Chemical and physical water quality parameters havebeen analyzed in a synoptic study of 101 lakes and103 rivers and streams in Hoylandet, a coastalcatchment in Central Norway. The area is sparselypopulated and most sites were unaffected by localpollution. Cambro-Silurian sedimentary rocks,porphyric granites and migmatitic gneisses arerepresented within the area and gave variableconcentrations of dissolved salts in surface water.Conductivity varied from 0.6 to 20 mS m-1 and pHfrom 5.0 to 7.6. Salt from sea spray dominated indilute water in more elevated parts of the catchmentwhile chemical weathering products were dominant inlower. The concentrations of all major ions and pHdecreased with increasing elevation. Non marinesulfate occurred in moderate concentrations. pHvalues less than 5.5 were rare and the area as a wholedid not seem to be subject to acidification.