Zmiany wielkości i struktury przestrzennej lesistości a rozwój sieci obszarów chronionych na Roztoczu w XX w.

The aim of the study is to assess the size and the spatial distribution of forest cover change in Roztocze in the period 1930-1990, the identification of main causes and the connection with the system of protected areas. Different types of protected areas in both Polish and Ukrainian part of Roztocze were selected as test areas. High rank of natural values of Roztocze area justifies this selection. In 2011, Biosphere Reserve was created in the Ukrainian part and Transboundary Biosphere Reserve Roztocze will be created in the near future, including the Polish part. The area of TRB Roztocze will include the most important protected areas in the Polish and Ukrainian part of Roztocze, where the forests are a significant element of biodiversity.The study was based on the spatial data on forest areas and built-up areas obtained from topographic maps at scale 1: 100 000 made in the 30s and 90sof the twentieth century. Maps selection was preceded by query cartographic materials and the assessment of their suitability for these types of researches. The spatial analysis methods (GIS) were used in the studies, mainly cartometric methods. Their results are presented on maps using cartographic methods of presentation: ranges and cartograms.The study showed that in Roztocze region the forest area increased by over 20% in the analyzed time period (approx. 60 years). This situation refers mainly to protected areas situated on Roztocze Rawskie and Tomaszowskie. However, there was almost no changes recorded in the case of Roztocze Gorajskie, where the protected areas are the smallest. The main reason for the forest area increase were settlement changes (many of villages on the Polish-Ukrainian border zone disappeared after World War II) and forestry succession on rural areas. The forest area reduction was caused by the spatial development of urban centers such as Tomaszów Lubelski, Józefów and a formation of the military training ground in the Ukrainian part of Roztocze.