不同品种高羊茅对石油污染土壤的修复效果及其根际微生态研究

发布时间：2018-06-01 18:34

本文选题：石油污染土壤 + 高羊茅　；参考：《安徽师范大学》2017年硕士论文

【摘要】：伴随着石油开采和加工产业的持续增长,大量石油及其产品进入环境,导致石油污染土壤已经成为当今社会急需解决的环境问题。由于石油中含有多种有害的持久性的有机污染物,因此污染土壤不仅会对生态环境造成极大危害,也会影响人类健康。因此,寻求经济有效的修复方法仍是当前国内外研究的热点。相较于传统的物理化学方法,植物修复技术利用植物根系和土壤微生物的相互作用去除有机污染物,具有不产生二次污染、经济有效、并能够产生相应的生态景观价值等优点。在诸多修复植物中,高羊茅是一种根系发达、适应性强、分布广泛的多年生草本植物,对石油污染土壤具有良好的修复效果。但高羊茅品种众多,且不同品种生活习性、修复效果都有很大差异,目前关于筛选高效修复石油污染土壤的高羊茅品种的研究尚未见报道。因此,在修复过程中有必要开展高羊茅品种筛选,并探讨其修复机制,以便更好地开展实际修复工作。本研究通过盆栽试验,研究了 14个不同品种高羊茅对石油污染土壤的修复效果和根际微生物群落的影响;修复过程中土壤微生物群落与石油烃去除效率之间的关系;通过分析高羊毛根系分泌物对污染土壤的修复效果及微生物群落变化的影响,明确根系分泌物在实际修复过程中的潜在应用价值,深入探究植物与微生物的联合修复的作用机制。主要研究结果如下:(1)盆栽修复试验表明,高羊茅对石油烃具有良好的修复效果,但不同品种对土壤中石油的去除效果具有显著差异。其中品种太阳神对总石油烃的修复效果最好达到49. 4%,猎狗五号修复效率最低,仅有18.7%。另外研究发现,与石油污染物降解相关的功能微生物,如诺卡氏菌属(Nocardia)、溶杆菌属(Lysobacter)、假黄杆单胞菌属(Pseudoxanthomonas)、分枝杆菌属(Mycobacterium)、红球菌属(Rhodococcus)和浮霉状菌属(Planctomyces),其相对丰度较对照处理组显著增加,但在猎狗五号、可奇思和绿溪处理组中其相对丰度与其他修复效果较好的品种处理组相比却呈明显下降的趋势。总体而言,土壤中石油的去除效果与功能微生物的相对丰度变化呈正相关。(2)通过前期研究,明确了不同品种高羊茅对污染物的去除效率具有显著性差异,并对土壤微生物的群落结构和相对丰度产生了不同程度影响,在前期实验研究的基础上,筛选了瑞星、自豪、绿溪和雅典娜四个品种进行进一步的研究。其中,瑞星和自豪处理组对总石油烃的修复效果最好,绿溪的修复效率最低。在植物修复的过程中,微生物的数量和活性呈先上升后下降的变化趋势。(3)棕榈酸是高羊茅根系分泌物的主要有机酸之一,能够显著促进与降解相关的功能微生物的生长,从而促进石油污染物的去除。不同浓度的有机酸均能显著促进石油污染物的修复,但不同浓度、不同组分的有机酸及其衍生物对修复效率和土壤微生物产生了不同程度的影响。修复效果较好的处理组中与降解相关功能微生物的相对丰度的增加也更为显著,这表明特定的根系分泌物、有机酸的成分及其浓度会引起微生物群落组成的变化,从而对修复效果产生不同程度的影响。
[Abstract]:With the continuous growth of the oil mining and processing industry, a large number of oil and its products have entered the environment, which has caused the oil contaminated soil to become an environmental problem urgently needed to be solved in the society today. As the oil contains many harmful persistent organic pollutants, the contaminated soil will not only cause great harm to the ecological environment, but also the shadow of the soil. Therefore, the search for economic and effective restoration is still a hot spot at home and abroad. Compared with the traditional physical and chemical methods, the phytoremediation technology uses the interaction of plant roots and soil microbes to remove organic pollutants, which has no two pollution, is economical and can produce the corresponding ecological landscape. In many restoration plants, tall fescue is a kind of perennial herb with developed root system, strong adaptability and wide distribution, it has good restoration effect on oil contaminated soil. But there are many varieties of tall fescue, different varieties of living habits, and the effect of restoration are very different. The study of Tall Fescue Varieties in soil has not yet been reported. Therefore, it is necessary to select the varieties of tall fescue in the process of restoration, and to explore its repair mechanism, so as to better carry out the practical repair work. In this study, the potted experiment was conducted to study the restoration effect of 14 different varieties of tall fescue on the soil contaminated by stone oil and the rhizosphere microorganism. The relationship between soil microbial community and petroleum hydrocarbon removal efficiency during the process of restoration; the potential application value of root exudates in the actual restoration process by analyzing the effect of the root exudates on the remediation of contaminated soil and the change of microbial communities, and exploring the joint repair of plant and microorganism. The main research results are as follows: (1) the potted plant repair test shows that tall fescue has good repair effect on petroleum hydrocarbon, but the effect of different varieties on the removal of oil in the soil has significant difference. The best repair effect of variety Sun God to total petroleum hydrocarbon is 49.4%, the efficiency of Hound five repair is the lowest, only 18.7. Other functional microorganisms, such as Nocardia, Lysobacter, Pseudomonas sp. (Pseudoxanthomonas), Mycobacterium (Mycobacterium), red hnococcus (Rhodococcus) and floating mycophenolate (Planctomyces), are found to be related to the degradation of petroleum pollutants, and their relative abundance is significantly higher than that of the control group. But in hound five, the relative abundance of CaCO and green Creek treatment group was significantly lower than that of other varieties with better restorative effects. In general, the removal efficiency of oil in the soil was positively correlated with the relative abundance of functional microorganisms. (2) through the previous study, it was clear that different varieties of tall fescue were polluted. The removal efficiency of the dye has a significant difference, and has different influence on the community structure and relative abundance of soil microorganism. On the basis of the previous experimental study, four varieties of Ruixing, proudly, green brook and Athena were selected for further study. Well, the restoration efficiency of green Creek is the lowest. In the process of phytoremediation, the number and activity of microbes are rising first and then decreasing. (3) palmitic acid is one of the main organic acids in the root exudates of tall fescue, which can significantly promote the growth of functional microorganisms associated with degradation, thus promoting the removal of petroleum pollutants. Organic acids can significantly promote the remediation of petroleum pollutants, but the organic acids and their derivatives of different concentrations and components have different effects on the repair efficiency and soil microorganism. The relative abundance of the biodegradation related functional microorganisms in the better treatment groups is also more significant, which indicates the specific root. Secretions, the composition and concentration of organic acids can cause changes in the composition of microbial communities, thus affecting the repair effect to varying degrees.
【学位授予单位】：安徽师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X53;X173

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