矿化垃圾强化微生物修复菲污染土壤研究

发布时间：2018-02-26 04:02

本文关键词： 矿化垃圾多环芳烃菲浓度作用机制微生物多样性　出处：《西南交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：由于各种矿物燃料、木材、纸和其他含碳氢化合物的不完全燃烧以及石油在开采、生产和运输过程中的泄露使得土壤中的多环芳烃增多,多环芳烃在土壤中具有稳定性高、降解性难、毒性强、具积累效应等特征而受到环境科学研究工作者的广泛关注。同时,矿化垃圾具有松散的结构、较好的水力传导性能和数量庞大的微生物,是一种优良的生物介质,因此,把矿化垃圾用于多环芳烃污染土壤修复具有较好的应用前景及现实意义。本文以人工配制的菲污染土壤为对象研究了矿化垃圾强化微生物修复不同浓度菲污染土壤的效果,并通过设置自然降解对照、添加灭菌矿化垃圾对照及添加营养物质对照研究了矿化垃圾强化微生物修复菲污染土壤的作用机制,主要的研究结果如下:1.浓度试验表明:添加矿化垃圾后,①菲污染土壤中总微生物量随时间先迅速增力加,从第13d开始降低,最后较为稳定,当土壤中菲的浓度在50～400mg/kg时,总微生物量和土壤中菲的浓度没有明显相关性;②土壤中多酚氧化酶活性随时间先降低,在修复的第39d时略有上升,然后又降低,最后较为稳定,当土壤中菲的浓度在50～400mg/kg时多酚氧化酶活性和土壤中菲浓度没有明显相关性;③不同浓度下小麦种子的发芽率相差不大,均在75%～95%之间;不同菲浓度土壤中小麦根伸长抑制率、芽伸长抑制率差距较小,说明在菲浓度为50～400mg/kg之间土壤生态毒性受土壤中菲含量影响较小。④对菲的降解动力学进行模拟后可以得出不同浓度下菲的降解速率相差不大,降解常数在0.434～0.637之间,菲浓度为50～400mg/kg菲的降解速率和土壤中菲的浓度没有明显相关性。⑤当土壤中菲浓度低于400mg/kg时,矿化垃圾在修复高浓度菲土壤有较好的优势。2.机理试验表明:①添加矿化垃圾和添加灭菌矿化垃圾的土壤其微生物总量明显高于自然降解土壤,说明矿化垃圾的加入能够促进土壤中微生物的生长;②添加矿化垃圾后在修复的前39d 土壤中的微生物由于竞争会使与多酚氧化酶相关的微生物活性降低,在修复的第49d后,添加矿化垃圾土壤中的多酚酶活性更高;③经过修复后,添加矿化垃圾的土壤中土壤生态毒性改善比未添加矿化垃圾的土壤好;④通过模拟得出的降解动力学方程可以看出添加灭菌矿化垃圾土壤中菲的降解速率最大,其次是添加矿化垃圾的土壤和添加营养物质的土壤,最后是自然降解土壤,说明矿化垃圾促进菲降解与其所含的营养物质有关。⑤从微生物多样性可以看出,添加矿化垃圾后菲污染土壤中细菌和真菌的数量分别提高了 2.75倍和8.92倍;细菌chaol指数增加了 0.78倍、Shannon指数增加了 0.20倍,说明细菌物种丰富度和群落多样性均有所提高;真菌chaol指数减小了 0.44倍、Shannon指数减小了 0.53倍,说明真菌的物种丰富度和群落多样性均有所降低。通过以上强化效果和作用机制的分析,可以为矿化垃圾强化微生物修复多环芳烃提供理论基础和技术支持。
[Abstract]:Due to a variety of fossil fuels, wood, paper and other hydrocarbons containing incomplete combustion and oil leakage in the mining, production and transportation of the PAHs in soil increased, PAHs in the soil has high stability, degradation of hard, strong toxicity, wide attention has accumulated features effect by environmental workers scientific research. At the same time, aged refuse has a loose structure, good hydraulic conductivity and large number of microorganisms, is an excellent biological medium, therefore, the mineralized refuse for PAHs pollution has a good application prospect and practical significance. Based on the artificial soil remediation of phenanthrene contaminated soil as research object the aged refuse enhanced microbial remediation effect of different concentrations of phenanthrene contaminated soil, and by setting up the natural degradation control, add sterilization and nutrition adding mineralized waste control Material control study of mineralized refuse mechanism enhanced bioremediation of phenanthrene contaminated soil. The main results are as follows: 1. showed concentration test: adding mineralized refuse, total microbial 1 of phenanthrene polluted soil with time rapidly enlarge, from the 13D began to decrease, finally more stable, when the soil phenanthrene concentration in 50 ~ 400mg/kg, there was no significant correlation between the concentration of total microbial biomass and soil phenanthrene; polyphenol oxidase activity in the soil with time first decreased and increased slightly in the 39d repair, and then decreased, finally more stable when the concentration of phenanthrene in soil in 50 ~ 400mg/kg and polyphenol oxidase activity in soil there was no significant correlation between the concentration of phenanthrene; the different concentration of wheat seed germination rate had little difference, both in the 75% to 95%; the concentration of soil phenanthrene in different wheat root elongation rate, bud elongation inhibition rate than the gap Small, in the phenanthrene concentration between 50 ~ 400mg/kg soil ecological toxicity affected by phenanthrene content in soil is smaller. The degradation kinetics of phenanthrene was simulated that the degradation rates of phenanthrene degradation under different concentrations had little difference, constant was 0.434 ~ 0.637, 50 ~ 400mg/kg for phenanthrene concentration of phenanthrene degradation rate and soil the Philippines has no obvious correlation. When the phenanthrene concentration in soil is lower than 400mg/kg, aged refuse test showed advantages of.2. in good repair mechanism of high concentration of soil phenanthrene: addition of mineralized refuse and add sterilization of mineralized refuse soil microbial amount was significantly higher than that of natural degradation of soil, indicating that addition of mineralized refuse can promote soil microbial the growth of the aged refuse; add in the repair of 39d soil microorganisms due to competition will make the microbial activity associated with polyphenol oxidase decreased in The 49D repair after adding polyphenol enzyme activity in the soil mineralized waste is higher; and after repair, adding mineralized refuse in soil to improve soil ecological toxicity than add mineralized waste of good soil; the degradation kinetic equation obtained by simulation shows that adding degradation rate of sterilization of aged refuse soil phenanthrene maximum secondly, adding mineralized refuse and soil nutrients in the soil, the last is the natural degradation of soil nutrients, that mineralized refuse phenanthrene degradation related. From the microbial diversity can be seen, after adding mineralized waste of bacteria and fungi in phenanthrene contaminated soil were increased by 2.75 times and 8.92 times bacteria; chaol index increased 0.78 times, Shannon index increased 0.20 times, that the bacterial species richness and community diversity were improved; fungal chaol index decreased by 0.4 4 times, the Shannon index decreased by 0.53 times, indicating that the species richness and community diversity of fungi were all reduced. Through the analysis of the above enhancement effect and mechanism, it can provide theoretical basis and technical support for strengthening microbial remediation of PAHs in aged refuse.

【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X53

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