Depth distribution of organic matter concentration and stocks in soils of Vojvodina

Despite the fact that soil organic matter (SOM) concentration is much lower compared to mineral portion, its importance is very valuable for soil fertility, agriculture, ecosystems and global environmental change. Soil organic carbon (SOC) is a key component of SOM. The amount of SOC varies greatly in surface layer of soil, but the vertical distribu?tion of SOC is also very important. The purpose of the study was to investigate vertical distribution of SOC in soil profiles of the most common soil types in Vojvodina (Arenosols, Chernozems, Fluvisols, Vertisols, Solonetz) and in different land uses (arable land, meadow and forest). Soil samples were collected from 0-30, 30-60 and 60-100 cm depth. Dichromate wet oxidation method proposed by Tyurin?s was performed to determine SOC concentration. Except arenosols, obtained results showed the decrease of SOC concentration with depth in all observed soil types and land uses. Vertisols had the highest SOC concentration in both surface (0-30 cm) and subsurface (30-60 cm) layers compared to the other soil types, while arenosols had the highest SOC concentration in the deepest layer (60-100 cm). Higher con?centrations of SOC in surface layers were measured in forests and meadows in relation to arable land, while in the lower layers these differences were not detected. Differences in SOC concentration in observed soil types and land uses were more pronounced in surface than in deeper layers. Soil organic carbon concentrations in deeper layers were substantially different only between soil types.