Technical reclamations are wasting the conservation potential of postindustrial sites
The view of postindustrial sites is rapidly changing, as many studies confirm their value as biodiversity refuges in many regions. Containing abiotic conditions actually rare in common European landscapes, they offer refugees for endangered species of early-successional habitats. In this context, the restoration method is crucial for their conservation potential. In abandoned limestone quarries in the Bohemian Karst, Central Czech Republic, the diversities of ten invertebrate groups and vascular plants of technically reclaimed and spontaneously developed plots were compared. The quarries hosted 69 species of national red lists (10% of all detected species), and many xeric specialists. Both specialists and endangered species were affiliated to non-reclaimed plots, while just the common generalists were affiliated with the technically reclaimed plots. These results were consistent across studied taxa. We showed the negative effects of very expensive technical reclamations of the post-mining sites. The high conservation potential of postindustrial sites could be realized by allowing succession to progress spontaneously. Given the decline of sparsely vegetated habitats, active restoration measures at postindustrial sites should be limited to maintenance of early successional stages.