A laboratory food-web mesocosm experiment was conducted following the design of the soil multi species test systems (SMS)described by (Scott-Fordsmand et al., 2008). In brief, the species composition of the SMS represents a Danish agroecosystem (Kroghet al., 1996). Six species were included: four Collembolan, one predatory mite and one enchytraeid. These belong to different functional groups with mutualism, competition, predation (and other less discriminated) interactions being represented. The soil was taken from a well-studied site with a history of Cu contamination and known Cu gradient. Soil, collected from clean and contaminated areas was first defaunated and then inoculated with a controlled microbial substrate. Soil community structure was followed over time, sampled at days 28, 61 and 84. Soil function parameters were also measured using bait lamina and litterbag tests to assess feeding activity and organic matter turnover, respectively. A total of 124 SMS units were prepared.