Spoil Heaps From Brown Coal Mining: Technical Reclamation Versus Spontaneous Revegetation

摘要

Vegetation samples from either spontaneously re vegetated or technically reclaimed spoil heaps of different ages in one of the largest active brown coal mining districts in Europe were analyzed and compared. The spoil heaps are located in the northwestern part of the Czech Republic and represent ages between 0 and 45 years. Ordination analysis (detrended correspondence analysis) showed that vegetation on technically reclaimed spoil heaps developed in a different way than that on spontaneously revegetated ones. The latter exhibited much higher species diversity in the oldest stages with the number of species doubled that of technically reclaimed sites. The oldest stages were also more advanced along an expected successional gradient as indicated by the ordination. Accelerating the vegetation development by technical reclamation was only of temporal character, whereas spontaneous succession proceeded further over the longer time scale. Spontaneous succession is advocated as an inexpensive and easy alternative to technical reclamation, because it leads to a more natural and rich vegetation cover. Unfortunately, technical reclamation is still the only approach considered in the present reclamation activities for this region.