Landscape geochemistry in Karkevagge, Swedish Lapland

This dissertation investigates the spatial and temporal nature of landscape geochemistry in Kärkevagge, Swedish Lapland. The research aims to understand the spatial and temporal changes in water chemistry in a small glacial valley from an empirical and experimental standpoint. The spatial nature of the water chemistry shows that pyrite oxidation and carbonate dissolution are the two reactions which control the chemistry of this silicate dominated landscape. These two reactions are so dominant that the rate of chemical denudation for Kärkevagge is approximately 46 tons per km2 per year, which is more in line with a sedimentary rock basin. The dissertation also investigated the ammonia/ammonium ion content of the rock materials which make up Kärkevagge. It was found that ion chromatography could be used to measure ammonium ion content of these rocks. An experimental weathering study was undertaken to investigate the potential impacts of increased atmosphere carbon dioxide on the rates of ammonia/ammonium ion and potassium release from the rock materials. A potential doubling or tripling of weathering rates could be expected from a tripling of atmospheric carbon dioxide.