Summary:

Forest surfaces, under which the exploitation of the hard bituminous coal takes place with “the infarction of the ceiling" method are the object of this work. The scope of research includes the surface of 6.2 square km of Zacisze and Ksiazenice forestries at the Forestry Commission Rybnik, located in the Mining Area of the Szczyglowice and Knurów coal mines. The applied way of extracting coal causes settling of the mountain base and transformations of forest surfaces. They manifest themselves mainly: with different deformations of the surface, development of hollows, inundated areas, as well as with changes in the natural-woody environment. The changes which are taking place are seriously curbing the possibilities of leading rational forest management on these areas. There is a most urgent need of creating a comprehensive way of redeveloping forests located in the mining areas. The plan of forest redevelopment will be based on the present and future changes of forest surfaces occurring under the influence of coal exploitation. This work shows methodology and research findings of forest surface transformations located in the zone of post exploitation descent of Szczygłowice and Knurów coal mines. Areas of intense transformations of forest surfaces were also outlined until the year 2015. In the research period till 2001 the majority of forest area in the Szczygłowice Mining District was transformed only in a low degree, about 376.5 ha that is 61% of the researched area. The second group consisted of areas with a medium degree of transformations and difficult accessibility - 99.9 ha that is 16% of the researched area. The size of the surface with a high degree of transformations included 86.2 ha that is 14% of the researched area. The remaining 55.5 ha that is 9% of the research area was located outside of the zone of descent. In the period till 2015 major changes will take place in the degree of transformations of the researched area. Lands with a medium and high degree of transformations will constitute the majority of the researched area and will be virtually inaccessible. They will take up approximately 327.7 ha that is 53% of the researched area. Only 24.8 ha that is 4% of the forest surface will remain outside of the descent zone. Results presented in the tabular and graphical form will be the base for further work on developing forests located in the areas of varying degrees of surface transformations.