哈密露天煤矿不同环境介质微生物群落特征分析

Microbial community characteristics of different environmental media in Hami open-pit coal mine

摘要:

【背景】干旱区露天煤矿开采过程中产生的粉尘颗粒物加剧了土壤生态环境的恶化和矿区空气质量的下降，针对煤矿区土壤和粉尘颗粒物的微生物群落组成的研究鲜有报道。【目的】研究新疆哈密南湖乡露天煤矿土壤、粉尘及大气PM_2.5颗粒物中的微生物群落结构和多样性特征，并预测潜在的功能类群。【方法】采用高通量测序技术，对煤矿露天采坑区和电厂粉煤灰堆放区的土壤、粉尘及大气PM_2.5颗粒物的微生物真菌及细菌群落组成进行比对分析。【结果】矿区优势真菌类群来自子囊菌门(Ascomycota)和担子菌门(Basidiomycota)，优势细菌类群来自变形菌门(Proteobacteria)和放线菌门(Actinobacteria)。真菌和细菌群落的丰富度及α多样性在整个矿区内无显著性差异，大气PM_2.5颗粒物的细菌群落生态位宽度显著大于露天采坑区和粉煤灰区。矿区内的土壤和PM_2.5颗粒物样本中均发现了一些丰度差异显著的功能类群，真菌特征功能类群为腐生营养型类群，细菌特征功能类群主要包括甲烷营养型类群、几丁质酶类细菌类群等。【结论】露天煤矿区粉尘可能对区域内土壤和PM_2.5颗粒物的微生物群落结构产生重要影响，具有煤组分降解功能的特定微生物类群可能是维持矿区土壤生态安全的重要微生物学机制之一。

关键词:露天煤矿;土壤;PM_2.5;微生物群落;营养功能类群

Abstract:

[Background] In open-pit coal mining in arid areas, the dust is destined to aggravate soil environment deterioration and air quality decline. A few studies on the microbial community structure in soil and dust particles in coal districts are available. [Objective] To study the microbial community structure and diversity of soil, dust, and atmospheric PM_2.5 from different functional regions in the open-pit coal mine in Nanhu Township, Hami, Xinjiang. [Methods] Illumina NovaSeq was employed for high-throughput sequencing to characterize the community structure and functional diversity of bacteria and fungi in the three media in the open pit area and fly ash area. [Results] Ascomycota and Basidiomycota dominated the fungi, while Proteobacteria and Actinobacteria were the dominant bacterial phyla in the coal district. The abundance and diversity of fungal and bacterial communities showed no significant difference in the entire coal district, but the niche breadth of bacterial communities in atmospheric PM_2.5 was significantly larger than that in the open pit area and the fly ash area. Some functional groups with significant difference in abundance were found between soil and atmospheric PM_2.5 in the coal district, such as saprophytic trophic fungi, methanotrophic bacteria, and chitinase-producing bacteria. [Conclusion] The dust produced in open-pit coal mining has important impact on the microbial community structure in soil and atmospheric PM_2.5 in the coal district. The specific coal components-degrading microbes are among the main contributors to the soil ecological safety in mining area.

Key words:open-pit coal mine;soil;PM_2.5;microbial community;functional-trophic group