# Peat Thickness Changes at the \"Wolosate\" Raised Bog in the Western Bieszczady Mountains
## 3 Study Results and Discussion  
The study demonstrated that the peatland dome has been successively lowering. The data on peat thickness at measuring points on the characteristic stratigraphic A-B transect of the bog dome (a study period of 1967-2016) are presented in Table 1.  
The change in the average peat thickness on the A-B transect (Table 1 and Figure 3, in relation to the beginning of the studied period in 1967, is, respectively: 1980 (\(-\)10.6%), 1988 (\(-\)34.3%), 2016 (\(-\)27.2%). Detailed analyses of the data for individual analyzed periods showed that in the years was recorded:  
* 1967-1980 the average lowering of the peatland area was \(-\)0.9 cm/year,
* 1980-1988 the average lowering of the peatland surface was \(-\)6.5 cm/year,
* 1988-2016, the average increase in the peatland surface by +0.6 cm/year. It follows that the greatest lowering of the peatland surface occurred in 1980-1988 by \(-\)6.5 cm/year. Such a rapid subsidence of the peatland surface was caused by the fact that 21 years earlier, the drainage of the entire Wolosatka stream valley had started. However, at the beginning of the 1990s, the Bieszczady National Park began the process of renaturation of the Wolosatka stream valley. As a result, the degradation process of the Wolosate bog was stopped, mainly in its western part, where at the core control points (core number 2-5) an increase in peat thickness from 17 to 78 cm was noted. Changes in peat  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{ \begin{tabular}{c} **Core** \\ **No** \\ \end{tabular}  } & \multicolumn{4}{c}{**Peat thickness (cm) in Subsequent Years**} \\ \cline{2-5}  & **1967** & **1980** & **1988** & **2016** \\ \hline
1 & 0 & 0 & 0 & 0 \\ \hline
2 & 69 & 62 & 37 & 104 \\ \hline
3 & 150 & 135 & 83 & 161 \\ \hline
4 & 250 & 22  
thickness throughout the analyzed period of 49 years (1967-2016) are also graphically presented on the transect of the peat dome (Figure 3). It is evident that compared to 1967, changes in the average peat thickness are unfavourable. A higher transect layer can only be observed on the western side, over a length of approx. 50 m. A similar situation occurs on a section of approx. 130 m (the western side) but only in relation to 1988. It can be assumed that this is the effect of restoration measures taken by the Bieszczady National Park. On the other hand, radically adverse changes took place on the studied transect (along a length of approx. 75 m, on its eastern side); this is illustrated by Table 1 and Figure 3.  
Figure 4 presents characteristic stratigraphic cross-section through \"Wolosate\" raised bog, developed on the basis of research in 2016 supplemented with data from the works of [12; 36]. Figure 4: A characteristic stratigraphic A-B transect through the “Wolosate” raised bog (1—_Sphagnum_ peat growing in tufts (_Eusphagnetti_), 2—cottongrass and _Sphagnum_ peat (_Eriophoro-Sphagnetti_), 3—Sphagnum and sedge peat (_Sphagno-Carcietti_), 4—woody alder peat (_Alneti_) with degree of decomposition R > 60%, 5—clayey formation, 6—European spruce _Pica abies_). Figure 3: Changes in the longitudinal transect of the “Wolosate” bog dome in the Western Bieszczady Mountain in the years 1967–2016 (1—mineral substrate, 2—the dome surface on 15 May 1967, 3—the dome surface on 12 June 1980, 4—the dome surface on 26 July 1988, 5—the dome surface on 5 May 2016). The dominant factor that affects the stratigraphic structure of peat deposits is the hydrographic conditions, and this changed during the analyzed period. The average annual level of groundwater at the top of the peat dome was 0.10m, while in the lower parts it was 0.21m. In the remaining research periods, the average groundwater level was, respectively: 0.28 m (0.10 m-0.48 m) in 1980, 0.35 m (0.12 m-0.57 m) in 1988, 0.21 m (0.00 m-0.42 m) in 2016.