Does acidification policy follow research in northern Sweden? The case of natural acidity during the 1990's

The situation in northern Sweden did not figure prominently in the intense period of research during the 1980's that laid the basis for many acidifica tion-related policies now in effect in Europe and Sweden. Northern Sweden h as not only relatively low acid deposition levels and significant sources o f natural acidity, but also intense episodes of pH decline during spring fl ood that are a major focus of liming activity. Controversy over that liming and natural acidity has led to scientific advances. These include discover y of a correlation between sulfur in snow and the anthropogenic contributio n to the subsequent spring flood ANC decline, but also that natural organic acidity is responsible for most of the spring pH decline in the region. Th is paper compares the developments in liming policy with the scientific dev elopments of relevance to the region during the last decade. Considerable d iscrepancies are noted which create opportunities for revising remediation policies to better reflect the state of knowledge in 2000.