菲胁迫下栾树与樟树根系活性的动态特征

发布时间：2018-03-12 22:37

  本文选题：菲　切入点：栾树　出处：《中南林业科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着工业化的发展和城市化水平不断提高,我国土地环境污染状况随之变得极为严重。利用植物来降解土壤有机污染物,修复环境污染是目前最具潜力的土壤生物修复技术之一。本研究选取栾树(Koelreuteria paniculata)与樟树(Cinnamomumcamphora)这两种我国南方城市常用的绿化树种为研究对象,拟定菲为多环芳烃代表物,设置菲浓度为LO:0 mg·kg~(-1),L1:100mg·kg~(-1),L2:1000 mg ·kg~(-1)3个处理水平,选取每一季度(Q1、Q2、Q3、Q4)的代表天进行取样,分析比较其根系分泌物中全碳、全氮含量及根系活性的季节动态,探讨其根系分泌物数量的动态特征及其在菲胁迫下根系分泌物的响应机制,以期为被PAHs污染的土壤提供植物修复的理论参考。同时,有望为城市森林布局、建设和管理提供重要的指导作用。其研究结果表明:栾树根系分泌物中TC、TOC的含量大多高于樟树。四个季度中栾树根系分泌物中TC的含量在Q1、Q2和Q4的L0处理水平下低于樟树,其余各季度各处理水平下均高于樟树,尤其是在L2处理水平下,两树种在Q2存在极显著性差异(P0.01),其余三季度也表现出显著性差异(P0.05);四个季度中栾树根系分泌物中TOC的含量Q1、Q2的L0处理水平下低于樟树,其余各季度均高于樟树,尤其是在L2处理水平下,两树种在Q2存在极显著性差异(P0.01),Q1、Q4也存在显著性差异(P0.05);栾树根系分泌物中TN的含量除在Q2的L0处理水平下低于樟树,其余各季度均高于樟树,并在Q1的L2处理水平下存在极显著性差异(P0.01),在Q3的L1、L2处理水平下均存在显著性差异(P0.05)。栾树根系总吸收面积和活跃吸收面积在四季度中,只有Q1的L0处理水平,Q2的L2处理水平,Q3的L0、L1处理水平低于樟树,其余各季度各处理水平均高于樟树。四个季度,栾树根系分泌物中TC、TOC与TN的含量经不同浓度菲处理后基本均高于樟树,这说明栾树根系分泌量大于樟树;栾树根系吸收总面积和活跃面积在L1、L2处理水平下有三个季度均高于樟树,这说明在菲胁迫下,栾树根系活性高于樟树。通过菲胁迫下根系分泌量和根系活性的比较,表明栾树对菲的添加表现出了一定的耐受作用,而樟树根系则表现出受胁迫现象,因此,栾树相较于樟树具有较好的耐菲的能力。
[Abstract]:With the development of industrialization and the increasing level of urbanization, the pollution of our country's land environment becomes very serious. Plants are used to degrade soil organic pollutants. Remediation of environmental pollution is one of the most promising soil bioremediation techniques at present. In this study, Koelreuteria paniculata and Cinnamomum camphora), two common greening trees in southern cities of China, were selected as the research objects, and phenanthrene was chosen as the representative of polycyclic aromatic hydrocarbons (PAHs). The concentration of phenanthrene was LO:0 mg 路kg ~ (-1) 路kg ~ (-1) 路kg ~ (-1). The seasonal dynamics of total carbon, total nitrogen content and root activity in root exudates were analyzed and compared by selecting the representative days of phenanthrene concentration as LO:0 mg 路kg ~ (-1) 路kg ~ (-1) 路L ~ (-1): 1: 1 mg 路kg ~ (-1) 路kg ~ (-1) 路kg ~ (-1) 路L ~ (-1). The dynamic characteristics of root exudates and the response mechanism of root exudates under phenanthrene stress were discussed in order to provide theoretical references for phytoremediation of soils contaminated by PAHs. The results showed that the content of TCU TOC in root exudates of Luan was higher than that of camphor, and the TC content in root exudates of Luan in four seasons was lower than that of camphor at Q1Q2 and Q4 L0 levels. In the other seasons, all the treatments were higher than those of camphor trees, especially under L2 treatment. There was a very significant difference between the two species in Q2, the other three seasons also showed a significant difference (P0.05), the content of TOC in root exudates of Luan was lower than that of camphor at L0 level in four seasons, and the other seasons were higher than that of camphor. Especially under L2 treatment, there was a very significant difference between the two species in Q2. The TN content in root exudates of Luan tree was higher than that of camphor tree in other seasons, except that in Q2 L0 treatment, there was also a significant difference in Q2 between the two species. There was a significant difference between L2 treatment and Q3 treatment in L2 and Q3, respectively. The total absorption area and active absorptive area of Luan tree root were all different in the fourth quarter, and there were significant differences in Q1 treatment and Q3 treatment in L2 and Q3 treatments respectively, and there were significant differences in Q1 treatment and Q3 treatment in L2 treatment and Q3 treatment in L2 treatment and Q3 treatment, respectively. Only Q1, L0, Q2, L2, Q3, L0 and L1, were lower than camphor, the other seasons were higher than camphor. The content of TCU TOC and TN in root exudates of Luan was higher than that of camphor after different concentrations of phenanthrene, which indicated that the root exudation of Luan was larger than that of camphor. The total area of root absorption and active area of Luan tree were higher than that of camphor tree in three seasons under L _ (1) L _ (2) treatment, which indicated that the root system activity of Luan tree was higher than that of camphor tree under phenanthrene stress, and the root exudation and root activity were compared under phenanthrene stress. The results showed that Luan had a certain tolerance to phenanthrene, while the root system of camphor showed stress. Therefore, Luan had a better ability to tolerate phenanthrene than camphor.
【学位授予单位】：中南林业科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X173;S792.99;S792.23
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本文编号：1603571