Biological soil crusts (biocrusts) are early colonizers of bare sand, forming a layer of microorganisms associated with soil particles. Former sand mines are examples of habitats that favor biocrust formation in a temperate climate. However, the flat area and slopes of sand mines create contrasting environmental conditions. In this study, we compared key biocrust functional indicators between biocrusts formed on flat areas and slopes to assess whether their traits support ecosystem functions, which may be useful in future restoration strategies. We expected that biocrusts on flat areas would exhibit higher microbiological activity due to more stable habitat conditions, whereas those on slopes would show higher exopolysaccharide (EPS) levels to reinforce slope stability. Our study showed that topography is an important driver of biocrust development and function, although its effects are closely intertwined with the dominance of photoautotrophic group. Biocrusts dominated by filamentous algae on flat area contributed to the improvement of soil conditions more effectively than cyanobacteria-dominated biocrusts developing on slopes owing to higher carbon fixation potential, stronger support for microbial activity, and better ability to maintain favorable moisture levels. On the other hand, cyanobacteria-dominated biocrusts contributed to soil stabilization and erosion control mainly through EPS secretion. Our results provide practical guidance for post-mining restoration by indicating that different biocrust types should be applied on slopes versus flat areas to improve restoration outcomes. We concluded that biocrusts can support ecosystem function and offer a promising tool for restoring former sand mines, especially where traditional vascular-plant-based methods are limited by unstable sandy soils. Keywords: Biological soil crust; Mesic areas; Slopes; Biocrust restoration; Anthropogenic disturbances; Open pit mining.