Spatial variability of enzyme activities in a 100-year old long-term field experiment

We attempted to clarify the importance of obtaining representative soil samples for microbiological purposes by comparing results from composite samples and individual cores taken at a depth of 30 cm from four different treatments at the “Static Fertilisation Experiment” in Bad Lauchstadt, Germany. As enzyme activities can be related to microbiological activities, we analysed alkaline phosphatase, β-glucosidase and protease activities from the composite and individual samples. When comparing both kinds of samples, protease activity was found to be the most and β-glucosidase activity the least variable parameter. Comparing just the individual cores, the greatest variation was found for alkaline phosphatase and the lowest variation for β-glucosidase activity; however, the latter enzyme activity also showed significantly different values. Thus, care should be taken when sampling in the field for microbial purposes.