Disposal of Sewage Sludge: Heavy Metal Fluxes in Norwegian Agriculture

Abstract

Heavy metal fluxes in Norwegian agriculture were estimated on the basis of annual sludge production, phosphate fertilization and crop production in the mail agricultural areas of Norway. Soil heavy metal input due to atmospheric deposition and output due to leaching were further included data from different reports.

In most cases, atmospheric was shown to be the most important source for Cd, Pb, Hg, Ni, and Cr while sludge, to be the most important source for Zn and Cu in Norway. Fertilization contributed the least proportion to soil input with respect to all seven heavy metals except for use of certain types of phosphate fertilizers with high cadmium concentrations.