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'Mining subsidence - a new challenge for Silesian environment' EDYTA SIERKA
University of Silesia, Faculty of Biology and Environmental Protection, |
Description popularizing the research project
Several hundred meters below the surface the ground looks like cheese. Extraction of coal seams and rocks has left cavities in the orogen. In places they have not been refilled the roof collapses under tensions and the ground caves in. Then if it happens in a city we can see a notice 'Caution! Mining Damage'.
When it happens in the midst of a forest nobody puts such notices and nobody cares about repairing the damage. Such a left alone subsidence soon starts a new life. First water fills the depression. Flooded roots suffocate without air and trees die making room for a lake. The lake in turn attracts plants which prefer wet areas. After a few years the lake has its own plankton and fauna. Tubifexes and other interesting animals inhabit its bottom deposits. In spring larvae of mosquitoes and dragonflies develop in the water. Soon amphibians will learn about a new lake and come to spawn there. More and more animals will settle down around the lake although life there is not easy. Because of its small size and capacity each season is in some way difficult. Summer heat often dries the lake. In autumn a thick layer of fallen leaves covers its surface, and in winter it freezes to the bottom. Nevertheless the squat, inhabited by enterprenous fauna and flora, becomes a sanctuary for them.
The forest lakes, so numerous in Silesia and known as flooded mine subsidences are mining damages. According to the legal regulations they ought to be leveled, reclaimed and renaturalized. In other words they should be removed. But is it the right thing to do so? We do not have too many lakes in our region. Certainly forest mine subsidences will not turn Silesia into Mazury Lake District but they can help us increase and keep the biodiversity received as an undeserved gift.
Abstract
At the end of prosperity of coal mining industry in Upper Silesia in Poland, in deformed areas new habitats were created which, in case of flooded mine subsidences, led to forming ecological niches of not encountered hitherto types. However, according to the regulations of "Geological and Mining Act" (Dz. U. No. 27, position 96 from 1.03.1994), after cessation of exploitation "one should take endeavors aimed to protect nature environment and start land reclamation as well as management of post coal-mining areas".
Basing on the legal regulations (the most frequently without taking into account natural viewpoint because of lack of complex plans) certain improvement actions are taken, so called land reclamations, which mean filling depressions up with barren rock and later afforestation.
Therefore, valuable ecosystems which are precious landscape elements affecting species and biocoenotic diversity - very important especially in industrialized areas, are destroyed.
The proposed research project is guided by main aim: to analyze qualitative and quantitative diversity of phytocoenotic systems occurring in areas of anthropogenic water ecosystems and in forests in their vicinity with regard to age and size of water reservoirs.