Changes of the Physical-Waters Properties of Murshic Endofibric Histosols in the Aspect of Long-Term Investigation on the Drainage Object Supraśl Dolna

The paper deals with the study upon changes within the physical and water properties of murshic endofibric histosols in the drainage meadow object Supraśl Dolna. The scope of studies includes the description of the soil profiles, thickness of diagnostic layer, bulk density, full water capacity, porosity, ash content, and peat decomposition. The long-term investigation carried out in 1982–2015 allows for observing the changes within these soils. The changes were studied in two habitats: wet and dry. In wet habitat, the groundwater flowed 30–98 cm below land surface and supplied the rhizosphere zone. Dynamics of groundwater surface were dependent on the size of precipitation during vegetation period and peat decomposition degree within the soil profile. In the dry habitat, the level of groundwater decreased up to 110 cm (below peat layer). Adverse water conditions in the dry habitat (temporal and long-term water deficiency) caused the increase in bulk density to 0.405 g·cm-3; simultaneously, a decrease in full water capacity to 82.5%, as well as faster peat mineralization occurred. In wet habitat, physical and water properties of murshic endofibric histosols were not significantly altered. In order to inhibit the peat decomposition rate and delay the peatland degradation, optimum moisture content should be maintained within the soil profile along with rational meadow management.