Influence of European beech (Fagus sylvatica) and Norway spruce (Picea abies) on composition of low molecular mass organic acids and on composition of microbial community in forest soils

Locations of interest for this diploma thesis are located in the Jizera Mountains and represent forest soils developed on acidic rocks (porfyric granite). The sites are tens of meters apart, making sure that all the abiotic conditions affecting the soil-forming process are very similar. The only significant difference between the localities is the species composition of the overstorey vegetation. On one site there is only the European beech (Fagus sylvatica), on the other only the Norway spruce (Picea abies). At both locations, soil samples were taken from each horizon L-B in which basic soil parameters and elemental contents (active and exchangeable soil reactions, moisture, cation exchange capacity, basic saturation, dissolved organic carbon and others) were analyzed. The low molecular mass organic acids were determined by ion-exchange chromatography. The bacterial phyla in the soil were calculated based on the Illumina sequencing to which preceded DNA isolation and quantitative PCR. Based on the results of the analyzes, the monitored soils were characterized as acidic with an unsaturated to strongly unsaturated soil sorption complex. Between the beech and spruce stands, differences in the contents of some water-extractable elements and the exchangeable elements (Ca, K, Mg, Fe, Al) and moisture..