Environmental consequences and the role of illegal waste dumps and their impact on land degradation.
Landfilling is an anthropogenic activity that may causes land degradation and pollution. During the landfilling of waste, a wide range of pollutants can be released into the environment, e.g. landfill gases and leachate. The existence of illegal landfills is an increasing global problem. Illegal uncontrolled refuse storage areas, commonly referred to as "illegal waste dumps" (IWD), occur most frequently on forest margins, in ditches, on the peripheries of inhabited areas as well as at other places. IWD contaminate soils, pollute water, change vegetation, ecosystem functionality, and pose land degradation. It was hypothesized that IWD can disturb the species composition of native vegetation and create space for synanthropic as well as invasive plant species. These species may then spread from the IWD and affect the species composition of the natural ecosystems. The objective of this study was to search localities with the occurrence of IWD (within the Slovak Republic), to identify the types of waste, to assess the vegetation species composition, and based on the obtained results to determine the environmental impact. The monitored sites contained primarily municipal refuse and construction and demolition waste. The municipal refuse included plastic materials, glass and textiles. Tiles, pieces of concrete and insulation materials represented the construction and demolition waste. The results show that IWD represent specific habitats for plants. What is more, disturb the species composition of native vegetation and create space for the enforcement of synanthropic species as well as invasive plant species. The novelty of this work is that monitoring of vegetation can positively contribute to the evaluation of impacts of IWD on the environment. IWD should be removed and the concerned localities should be cleared, restored and reclaimed.