The differentiation of soil parameters is most frequently studied between soil horizons. However, in drained organic soils, mursh-forming process changes the peat into mursh in the topsoil, which layers may behave differently. The aim of the study was to characterize how soil chemical properties and labile carbon pool respond to mursh-forming process at three depths:  0-10 cm, 10-20 cm and 20-30 cm as well as at various TOC levels. Secondly, we attempted to answer the question whether different labile carbon fractions have the same response and can be regarded as indicators of the changes in mursh. In the study we determined the following soil properties: organic matter, carbon, nitrogen contents, hot and cold water-extractable carbon (HWC and CWC), calcium chloride extractable carbon (CaCl2-C), soil sorption properties, bioavailable forms of Fe, Mn, K, Ca, Mg, Zn, Cu. The results of the study revealed that the studied soil properties were changing along with the depth and were also dependent on total organic carbon contents. Most of decomposable and mineralizable organic matter occurred in the 10-20 cm or 20-30 cm layers, especially when HWC or CaCl2-C were taken into account. The variability of the results among studied depths was explained in PCA analysis by organic matter and carbon contents as well as soil sorption properties, Zn content and labile carbon fractions contents, mainly HWC. The study revealed that HWC is an excellent indicator of changes occurring under mursh-forming process whereas CWC proved to be ineffective.