This project aims to increase the understanding of how soil characteristics such as pH, organic matter content, and soil solution characteristics influences on the bioavailability and toxicity of two metals - copper and cadmium - to selected soil organism s. The link between chemical speciation and the toxicity of these metals in soil will be investigated by combining information on their metal geo- and hydrochemistry (chemical measurements and speciation models) with experimental data on their toxicity to terrestrial plants, invertebrates and micro-organisms. Some experiments will be performed in both single-species and two-species (plant-earthworm) test systems, to see if metal bioavailability may be changed by the presence of other species.