Abstract:
The metal tailings pond is a typical degraded habitat with high soil heavy metal content, low fertility, poor matrix structure and low vegetation coverage. To study the biological soil crust, samples were collected from two abandoned tailings ponds in 2016 from Huangshi City, Hubei Province to assess the species composition by spatial sequence method rather than time successional sequence. The absolute abundance of cyanobacteria, fungi and moss in the crusts were (0.63-2.01)×10
8, (0.19-1.53)×10
8 and (0.08-3.34)×10
7 copies/g DW soil, respectively, and the abundance of moss increased with the decreased abundance of cyanobacteria and fungi. A total of 41 species were analyzed from the biological soil crusts, in which Proteobacteria, Cyanobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Verrucomicrobia, Acidobacteria, Planctomycetes, Gemmatimonadetes and Thermomicrobia were the main components. The accumulative abundance in different crusts was more than 90%. The composition and successions of biological soil crust in the metal tailings ponds are similar to those in the desertified area, and Cyanobacteria have an irreplaceable role. Studies have shown that biological soil crust can be widely distributed in metal tailings ponds, and can enrich the soil nutrients in the tailings pond, which can be widely used for ecological restoration of metal tailings ponds.