中条山铜尾矿库坝面土壤微生物群落结构特征

发布时间：2018-11-05 20:22

【摘要】：中条山铜基地是我国七大铜基地之一,位于山西省垣曲县,是非煤地下开采矿山,铜储量300多万吨,年采矿700万吨,选矿720万吨。采矿活动造成环境破坏和土壤重金属污染,重金属通过食物链在动植物和人体中积累,影响人身体健康。植物定殖可以吸收、转移、挥发土壤中的重金属。微生物是土壤生态环境中最重要、最活跃的部分,其参与地球生物化学循环、降低重金属的毒害、改善土壤质量、促进植物健康生长。在贫瘠脆弱的生态环境中,微生物可作为土壤恢复的敏感指标,微生物的群落结构和多样性动态,有助于了解矿区土壤的生态恢复状况。本文以细菌16S rDNA V3区和真菌ITS1区高通量测序的结果,分析了3个恢复时间段的铜尾矿库坝面土壤微生物群落结构;并通过变性梯度凝胶电泳(DGGE)分析了6个恢复梯度坝面土壤细菌群落多样性变化的时空动态,进一步分析了尾矿库坝面土壤恢复过程中,微生物群落的结构特征及构建机制。得出以下结论:1)尾矿库坝面土壤环境因子动态特征研究区坝面重金属Cu、Pb、Cd和As超标,Cr、Ni和Zn均不超标。土壤pH随恢复时间差异显著,恢复30年、15年和1年样地高于45年、40年和5年样地。在不同季节,土壤pH在4月份高于7月、9月和11月。土壤养分含量沿恢复时间变化明显。土壤TC和TN从45年和40年样地到30年和15年,呈降低趋势。9月和11月的养分(TC和TN)高于7月和4月。TS在9月和11月含量最高。2)尾矿坝植物群落多样性变化动态野外调查分析植物群落多样性的变化。植物Shannon指数随恢复时间变化明显,45年和40年样地显著高于30年、15年和5年样地。Pielou指数在不同样地间差异不显著。植物Shannon指数与Simpson指数在不同季度间变化不明显。3)尾矿坝土壤质量变化情况土壤质量(土壤酶活性和土壤呼吸)与土壤养分含量变化趋势一致,随不同恢复时间形成演替变化。土壤脲酶和蔗糖酶活性在9月和11月较高,过氧化氢酶活性在11月最低。土壤呼吸在45年、40年和5年样地9月最弱,但在30和15年样地4月最弱。土壤质量主要受到养分含量、植物群落多样性和微生物群落结构的影响。重金属(Mn和Pb等)含量抑制土壤的恢复,但对其作用较小。4)尾矿坝微生物群落结构特征及影响因素采用Illumina MiSeq平台对尾矿坝45、15和1年样地进行高通量测序,尾矿坝不同梯度的土壤细菌优势门有变形菌门、放线菌门和厚壁菌门等。土壤真菌优势门有子囊菌门、接合菌门和担子菌门。非度量多维测度(NMDS)和mantel test分析结果表明土壤理化性质、重金属含量、植物群落多样性和土壤质量影响细菌和真菌群落结构变化,且土壤细菌与真菌相互作用显著。其中,变形菌门的鞘脂单胞菌科(Sphingomonadaceae)对重金属有一定的耐受性,可以指示重金属的污染程度。5)尾矿坝细菌群落多样性时空动态通过变性梯度凝胶电泳(DGGE)分析尾矿坝6个梯度,4个季节细菌群落结构的多样性变化。尾矿坝细菌群落Shannon指数和Richness指数与土壤恢复年限关系显著,与土壤养分含量和土壤质量变化趋势一致,但是Simpson指数和Pielou指数随恢复时间变化不明显。在45年、30年和15年样地中,7月细菌群落多样性(Shannon指数和Richness指数)显著高于11月。RDA分析结果表明,细菌群落多样性(Shannon指数和Richness指数)主要受到土壤养分含量(TC和TN)变化的影响。结构方程模型(SEM)结果表明在7月、11月和4月理化性质和土壤质量是土壤细菌群落多样性变化的主要影响因子,但在9月份,理化性质和植物多样性对细菌多样性的作用更大。
[Abstract]:Zhongtiaoshan Copper Base is one of the seven largest copper bases in China. It is located in Qqu County of Shanxi Province. It is a non-coal underground mining mine, with copper reserves of more than 3 million tons, annual mining of 7 million tons, and mineral separation of 7.2 million tons. Mining activities cause environmental damage and soil heavy metal pollution. Heavy metals accumulate in animals and plants and human bodies through the food chain and affect human health. Plant colonization can absorb, transfer, and evaporate heavy metals in soil. The microorganism is the most important and active part of the soil ecological environment, which participates in the biochemical circulation of the earth, reduces the toxicity of heavy metals, improves the soil quality and promotes the healthy growth of plants. In barren and fragile ecological environment, microorganism can be used as sensitive index of soil recovery, microbial community structure and diversity dynamics, which can help to understand the ecological restoration status of soil in mining area. Based on the results of high-throughput sequencing of bacterial 16S rDNA V3 region and fungal ITS1 region, the microbial community structure of soil microbial community in three recovery time periods was analyzed. By denaturing gradient gel electrophoresis (DGGE), the temporal and spatial dynamics of soil bacterial community diversity in six restoration gradient dams were analyzed. The conclusions are as follows: 1) The heavy metals Cu, Pb, Cd and As in the dynamic characteristics of soil environmental factors in the dam face are not exceeding the standard, and Cr, Ni and Zn are out of the standard. Soil pH was significantly different with recovery time, recovered for 30 years, 15 years and 1 year, and was more than 45 years, 40 years and 5 years. In different seasons, soil pH was higher in April than July, September and November. The soil nutrient content changes obviously along the recovery time. Soil TC and TN decreased from 45 and 40 years to 30 and 15 years. The nutrients (TC and TN) in September and November were higher than July and April. TS was the highest in September and November. 2) Dynamic field investigation of plant community diversity in tailings dam analyzed the variation of plant community diversity. The plant growth index changed significantly with the recovery time, significantly higher in 45 and 40 years than in 30, 15, and 5 years. Pielou's index was not statistically significant. The change of soil quality (soil enzyme activity and soil respiration) in tailings dam was consistent with the variation trend of soil nutrient content. The activity of soil and sucrose was higher in September and November, and catalase activity was lowest in November. Soil respiration was the weakest in 45, 40, and 5 years, but was weakest in April and 15. Soil quality is mainly influenced by nutrient content, plant community diversity and microbial community structure. The contents of heavy metals (Mn and Pb, etc.) inhibit the recovery of soil, but have little effect on it. 4) The structural characteristics and influencing factors of microbial community of tailings dam adopt Illumina MiSeq platform to carry out high-flux sequencing on tailings dams 45, 15 and 1 year, and the soil bacteria advantage gate with different gradient of tailings dam has deformation bacteria door. Actinomyces and thick-walled bacteria doors, etc. The fungal dominant gate of the soil has a fungus gate, a joint fungus door, and a basidiomycetous door. The results of non-metric multi-dimensional measure (NMDS) and mel test show that soil physical and chemical properties, heavy metal content, plant community diversity and soil quality affect bacterial and fungal community structure changes, and soil bacteria interact with fungi. Among them, Sphingaradaceae has a certain tolerance to heavy metals, The pollution degree of heavy metals can be indicated. 5) The spatial and temporal dynamics of bacterial community diversity in tailings dam are analyzed by denaturing gradient gel electrophoresis (DGGE), and the diversity of bacterial community structures in 4 seasons is changed. The relationship between the Shannon index and the Richards index of the bacterial community in the tailings dam was significantly related to the soil restoration years, but the Simpson index and the Pielou index were not obvious with the recovery time. In the 45-year, 30-year and 15-year-like plots, the bacterial community diversity was significantly higher in July than in November. The results showed that the bacterial community diversity (Shannon index and Richness index) was mainly influenced by soil nutrient content (TC and TN). The results of structural equation model (SEM) indicate that the physical and chemical properties and soil quality in July, November and April are the main factors affecting the diversity of soil bacterial communities, but in September, the physical and chemical properties and plant diversity play a greater role in bacterial diversity.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S154.3

【参考文献】