Soil small-scale microcosms showed to be suitable for assessing the effects of Bt-toxins (crystal (Cry) proteins), copper and plant material containing Cry-proteins on the structure of nematode communities (Höss et al. 2014). The microcosms are 50-ml centrifuge tubes filled with approx. 30g of soil (see Fig. 1). In this small volume of soil, a sufficiently high number of nematodes is present to perform a statistically valid analysis of the community structure.