Macroinvertebrate/sediment relationships along a pesticide gradient in Danish streams

摘要: Twenty-nine Danish streams were investigated in September 1998. The drained catchments of varying hydrology, topography, soil type and land use. In each stream, the newly accumulated streambed sediment was sampled subsequently analysed for pesticides. five replicate macroinvertebrate samples taken same sediments as pesticide samples. addition, riffles to provide a complete picture community composition. number detected pesticides reflected use: agricultural on clay soils average 4.3±2.2; sandy 2.6±1.0, while only 1.5±0.6 found without activities. composition showed clear changes along this gradient concentrations. amphipod Gammarus pulex negatively correlated with concentration, Oligochaeta Hirudinae positively correlated. findings indicate that have potential structure communities streams. However, impact is more than pesticides, several other factors, such channelisation, affect these are not easily separated.