EN
Intense changes in the land use of lake catchment basins in the Polesie Lubelskie region (E. Poland), observed over the last decades, have a strong, significant effect on the functioning of lakes and wetlands in the landscape. One of the methods of investigating these changes is analysis of the network of land use boundaries. The studies included 11 basins of lakes located in 3 neighboring river valleys. Basing on the analysis of air photographs from the years 1952 through 1992, 55 types of land use boundaries (transitional zones) had been identified in that region. The changes, which had taken place during this period, related to the features like: character of the transitional zones, density of their network and size of the patches were also examined. Most stable and most transformed areas were pointed out. Suggestions concerning directions and methods of environmental protection in that region were formulated.