The area of the Horná Nitra region is to a large extent affected by the long term coal mining that spatially devastates the countryside. The method of brown coal mining used in the Nováky coal deposit activates surface deformations in cadastral area of the village Koš. Notable negative influences of mining are related not only to ecosystems of the original landscape, but also to essential demographic changes in career structure of its inhabitants. By means of comparison of landscape structure mapped in the years 1850, 1960, 1991 and 2007, changes in landscape utilisation have been evaluated. In relation to biodiversity development the most significant changes are recorded in enlarging of the surface of water bodies or in generation of new water bodies (24,66 ha). High biodiversity is linked to water bodies and wetlands: we documented the occurrence of 259 vascular plant species, 96 spiders species, 33 dragonfly species, 9 amphibian species, 7 ichthyic species, 185 bird species and 11 small ground mammals species. Under the current legislation, negative effects of coal mining have to be eliminated through reconstruction of the affected areas. It is obvious that all these measures require a large amount of financial sources. We found out that it is appropriate to leave these areas without any management intervention, because ongoing spontaneous processes result in an increase in local biodiversity and tend to restore ecological, economic, aesthetic and social functions of the landscape. Nowadays, the wetlands of Koš represent a biodiversity centre in the Horná Nitra region, with supra-regional importance as for bird species.