Abstract: | Scale-dependent spatial variability of microbiological characteristics in soil of a beech forest The spatial variability of the microbial biomass content (Cmic), the microbial respiration rate (basal respiration) and the metabolic quotient (qCO2) was analyzed in sandy Cambisols and Luvisols in a beech forest in Northern Germany. Highest variability of microbiological features and, thus, the distance of independent samples was around 10 m that is discussed with reference to spatial hierarchy. Structural changes between the 10 m and 50 m grid were suggested for the Ah horizon due to the break of correlations of Cmic content and the contents of Corg and plant-available Ca, Mg, K and Nt. The Cmic content correlated with the Corg content close to tree trunks and ecotones like borders of the forest and clearings. The qCO2 did not generally increase with declining pH value. High H+ concentrations and Corg content in the litter layer near to the tree trunk indicated retarded microbial mineralization rates. High proportion of microorganisms that are resistant to low pH value and adjusted ro readily-degradable substrates seems to dominate in the soil close to the tree. |