Figure 1. Conceptual impression of the scientific background and the experimental approach.

Organic matter (OM) and agricultural chemicals from agricultural fields enter the adjacent ditches either directly or via leaching through the soil, potentially affecting the degradation of organic matter. To investigate realistic effects of agricultural practices on OM quality, decomposition and consumption tablets (DECOTABs) were prepared from natural organic material (OM) collected from agricultural drainage ditches adjacent to either hyacinth bulb field or grass lands and plant material free from agricultural chemicals to account for the chemical composition of the OM. These DECOTABs were offered to invertebrate communities in the field and a laboratory incubation of the key detritivore Asellus aquaticus.