AN AUTOMATED MICROCOSM SYSTEM FOR STUDYING SOIL ECOLOGICAL PROCESSES

Soil ecological processes are characterized by high temporal and spati al variability. To evaluate effects of soil management and environment al parameters on single processes, it is necessary to investigate seve ral replicates of each soil type under controlled laboratory condition s. We developed a microcosm system in which 64 disturbed or undisturbe d soil columns, each controlled individually, may be evaluated. The te chnical design of the automated microcosm system demonstrates the broa d applicability of the system. For demonstration the effects of the he rbicide terbuthylazin (TA) on microbial respiration in microcosms trea ted with and without barley (Hordeum vulgare L.) straw are shown. Even high amounts of the herbicide applied did not reduce the CO2 release by the soil organisms. The C source added with the barley residues did not change this result significantly.