The aim of the study was to determine the content of soil organic carbon (SOC) in various types of highland temperate meadows. The analysis covered 360 soil samples collected in 6 types of meadows in SE Poland. Meadows were grouped on the basis of the analysis of phytosociological records taken according to the Braun-Blanquet method. In the laboratory, pH in 1 mol dm-1 KCl solution, organic C content by the Tiurin method, general N form by the Kjeldahl method, and assimilable P and K forms by the Egner-Rhiem method were determined. In the calculation of SOC in kg ha-1, the 0-30 cm profile layer was analyzed, assuming an average soil weight equal to 103 kg m-3. Analyses showed that the SOC content significantly depended on the type of meadow (moisture, plant species composition), pH, N and P content, but no relationship with K was found. The average content of SOC varied depending on the type of meadow from 22.1 to 172.4 g kg-1 (66.44-517.35 kg 103 ha-1), with the highest value being in rush meadows, and the lowest – in psammophilic meadows. The total SOC stock estimated at work for the studied types of upland meadows (30921 ha) in SE Poland is 11.33 kg 109. The correlation of SOC with pH is positive, with easily discernable limits determined by 3.5 and 7 pH values, beyond which, in all tested meadows, the carbon content in the soil does not exceed 100 g kg-1. SOC is also positively correlated with the content of N and P in the soil. We have proven that the diverse habitat conditions of meadow ecosystems have an impact on the accumulation of organic carbon in the soil. It is necessary to consider the possibility of taking protective measures for these ecosystems of meadows in the temperate climate, which are characterized by the highest SOC accumulation. The implementation of such measures could positively affect the struggle against global warming, while preserving the mosaic landscape of fields, meadows and forests characteristic for this region.

25.1.2020