Archaea diversity of reclaimed soil in the coal gangue hill

Abstract

Coal gangue is the most discharged solid waste in the process of coal mining. The coal gangue hill formed by stacking brings serious environmental pollution to the surrounding environment. The vegetation reconstruction of the coal gangue hill is one of the effective ways to solve the huge accumulation of coal gangue and environmental restoration. The growth of plants can affect the number and diversity of soil microorganisms, while microorganisms can promote soil nutrient cycling. Current reports have focused mainly on bacteria, actinomycetes and fungi, but little is known about the composition and function of archaea in the coal gangue reclamation soil. In this study, PCR-16S rRNA gene high-throughput sequencing technology was used to investigate the diversity of archaea in the coal gangue soil reconstructed by vegetation, to enrich the ecological assessment of coal gangue hill. The results showed that the species richness and diversity of archaea were great different in different sampling sites. Thaumarchaeota (>90%) and SCG (>90%) was the absolute dominant phylum and class of archaea in the gangue soil, respectively. Identified dominant genus was unidentified_SCG (5.5%), and more than 90% of archaea genera were unidentifiable, indicating a large number of unknown archaea resources in this soil environment. SCG, as a kind of chemoautotrophic ammonia oxidizing archaea, plays potential roles in nitrogen cycling of the coal gangue reclamation soil.