## 4 Discussion  
Considering that the study area is 1754.5 ha, the carbon contribution to the environment is very important. It was estimated that this area provides 50.10-905.20 t ha\({}^{-1}\) of soil organic carbon to a 1 m depth. In a study on British forest soils [2], the authors noted high values of carbon stock (589 t ha\({}^{-1}\)) in the top 80 cm, and 664 t C ha\({}^{-1}\) in the top 1 m of soil, but their results were very dependent on climatic factors and soil type. In [26], the carbon stock in the forest soils of Europe was estimated to range between 1.3 and 70.8 t C ha\({}^{-1}\) for the O-layer and between 11.3 and 126.3 t C ha\({}^{-1}\) for the mineral soil to 0-20 cm. In [27], forest soil carbon stock of 79 Gt C was reported for all European soils, including peat. In [28], total stocks were estimated to be 3.50-3.94 Gt C on the forest floors and 21.4-22.7 Gt C in the mineral and peat soils to a depth of 1 m in European forests. The topsoil SOC values for agricultural soils across Europe were determined to range between 40 and 250 t C ha\({}^{-1}\)[29]. The highest SOC values were found in Ireland, the UK, the Netherlands, and Finland, all of which had values of \(>\)250 t C ha\({}^{-1}\) and correspond to peatland areas. The carbon stock in the mountain soils of BNP was comparable to the carbon stock for forest soils in other parts of Europe, and it is much higher than the average carbon stock in agricultural soils. Several papers confirm that the greatest organic carbon content is above a depth of 30 cm in different conditions [30; 31; 32]. The obtained results confirm the influence of topography on the accumulation of carbon in the soils of the BNP. The highest carbon stock was recorded in histosols, which are located in the lower positions of the BNP in valleys and on flat mountain areas. A high T-SOCstock was found in spruce stands created on podzols and located at higher altitudes. The temperature decreases with the altitude, which results in a slower rate of organic matter decomposition [33]. At the same time,  
Figure 10: Dendrogram with group identified in the cluster analysis. The altitude, slope, Total SOCstock and type of forest stands were used for diagram preparation (plots number plus symbol of different soil types, CD—dystrict cambisols, CE—eutric cambisols, FL—fuvisols, GL—gleysols, HI—histosols, PO—podzols, ST—stagnosols). low temperatures reduce the productivity of ecosystems [34]. In [35], the authors found that SOC stock showed a decreasing trend at higher elevations, which is where the forest vegetation types transform into alpine shrublands. Altitude importantly but indirectly influences the SOC stock by affecting properties such as lower soil depths, different distributions of forest species, different soil types, and increased percentages of stone content [7; 11; 36; 37]. In our study, the results of the PCA analysis confirm the importance of the slope in shaping the SOC stock. A lower slope position promotes vegetation growth, which results in higher SOC accumulation. In [38], it was suggested that, at the hill scale, the variability of soil organic carbon stock might be explained by the slope rather than the elevation. [39] observed a strong relationship between the slope and the quantity and quality of SOC accumulation in hillslope systems. Specifically, moderate slopes (15%) combined with a concave profile and plan curvature led to greater SOC accumulation. An important graphic factor that determines the accumulation of SOC in soils is the parent material [28; 38]. In our research, high SOC stock was associated with sediments accumulated on terraces, which occur in low-lying valleys and flat mountain areas and are characterized by strong waterlogging. The results of the cluster analysis identify high SOC stock in highly waterlogged soils. In [34; 40], the authors confirmed the relationship between SOC and soil water content, and soil moisture explained \(>\)50% of the total variation in SOC stock.