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[Objective] The present paper aimed to reveal the mechanism of action of soil bacterial community environment in woodland under different restoration patterns. [Method] Using high-throughput sequencing technology, we analyzed the relationship between soil physicochemical properties and dominant bacterial communities through the composition and diversity of soil bacterial communities in southern Aquilaria sinensis, Acacia mangium forests and natural secondary woodlands. [Result] (i) In the taxonomic study of soil bacteria in different forest stands, there were 44, 32 and 35 phyla of soil bacteria in the Aquilaria sinensis, Acacia mangium and secondary forest, respectively.The composition of soil bacteria in the three forest stands was relatively similar, and the dominant bacterial groups were Proteobacteria and Acidobacteria, and the communities with relative abundance ＞1% were all Actinobacteria, Verrucomicrobia and Planctomycetes. (ii) In the α-diversity analysis of soil bacteria in different forest stands, the highest Chao1 index of secondary forest soil indicated the highest bacterial community in this soil, and the highest Shannon index of soil sedum forest soil indicated high bacterial diversity in this soil. (iii) In the β-diversity analysis of soil bacteria in different forest stands, the soil bacterial community structure of soil sedum forest and Acacia mazanensis forest was differential, while the secondary forest had similar soil bacterial structure to the former two. (iv) In the RDA redundancy analysis of soils in different stands, Phytophthora variegata and Phytophthora floxa were significantly and positively correlated with fast-acting potassium, effective phosphorus and total phosphorus. Acidobacteria were negatively and significantly correlated with soil pH, effective phosphorus and fast-acting potassium. [Conclusion] The results reveal the structural variability and diversity of soil bacterial community composition in three different forest stands in Shenzhen, and provide a theoretical basis for further exploring whether the artificial restoration model is superior to natural forests. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to take the open-pit coal mining area in southern Karamari mountains as an example, the contents, enrichment characteristics and spatial distribution of heavy metals in typical desert plant Reaummuria soongorica（Rs）and surrounding soil were analyzed. The pollution status of six heavy metals, zinc, copper, chromium, lead, mercury and arsenic (Zn, Cu, Cr, Pb, Hg, As) was evaluated and their sources were explored. [Method] Mathematical statistics and GIS methods were used to analyze the enrichment characteristics and spatial distribution of heavy metals in bipachai, analyze the pollution sources and evaluate the potential ecological risk. [Result] The over-standard rates of Cr, Pb and As in soil samples were more than 70%, and the average values exceeded the background values of Changji. The over-standard rates of Hg in Rs samples were 23.08%. The enrichment coefficient (3.658) of Hg in Rs was much higher than that of other elements, indicating that Rs has a strong tolerance to Hg. Except for Pb, the retention rate of other elements was positive, indicating that there was a certain tolerance in the root of Rs. Zinc and copper mainly came from crustal sources, while other elements were affected by both human and natural factors, especially Hg, which was heavily affected by disturbance in mining area and seriously polluted. Potential ecological hazard assessment results showed that in soil and plant, Zn, Cu, Cr, Pb, As five elements were relatively light pollution, Hg pollution was more serious. The distribution of Cu, Cr and As in Rs was similar, which might come from same sources. The enrichment ability of Rs to As was related to the content of As in soil. [Conclusion] The content of elements exceeding the standard in the soil of the study area was low in Pipa. At the same time, Pipa had a certain tolerance and can be used as a dominant species for ecological restoration. [ABSTRACT FROM AUTHOR]