摘要：为了考察外源生物炭在桑树对土壤铅植物修复方面的影响，本研究采用盆栽的方式，设置不同浓度的土壤铅胁迫进行实验，考察了桑树的根系参数、叶绿素含量、光合参数、活性物质、损伤指标和铅积累情况。结果发现，外源生物炭提高了桑树的吸收根根长、根尖长度、根尖表面积，促进了抗坏血酸、类黄酮的生成和铅积累。生物炭处理对桑树的根冠比、平均叶面积、叶绿素含量及成分组成、蒸腾速率、气孔导度、净光合速率无显著影响。与无生物炭处理相比，外源生物炭处理不同程度地降低了GSH、非蛋白巯基两种活性物质的含量。综合分析，外源生物炭增强了桑树在铅胁迫下的适应性，减轻了铅胁迫对桑苗的毒害作用，在桑树对土壤铅植物修复方面具有积极作用，可应用于土壤重金属植物修复技术的研究。

关键词：土壤铅胁迫；生物炭；桑树；铅积累；活性物质

Abstract：In order to investigate the effect of exogenous biochar on the remediation of lead in mulberry soil, the experiment was conducted by using potting test and different methods of soil lead stress. The main detection include biomass, root parameters, chlorophyll, photosynthesis, active substances, damage indicators and lead accumulation. The results showed that exogenous biochar increased the absorb root length, absorb root tip length, absorb root tip surface area of mulberry and promoted the formation of ascorbic acid, flavonoids and lead accumulation. The effect of biochar on root/shoot ratio, average leaf area, E, Gs, Pn, chlorophyll content and its composition was not obvious. Compared with the control group, the exogenous biochar reduced the contents of GSH and NPT in different degrees. Comprehensive analysis, exogenous biochar enhanced the  adaptability of mulberry under lead stress, reduced the toxic effects of lead stress on mulberry seedlings, assisted mulberry to repair lead pollution in soil, and it can be used for soil heavy metal phytoremediation research.

Keywords：Soil lead stress; biochar; mulberry; lead accumulation; active substance

目 录

第一章 绪论 1

1.1重金属铅对土壤污染的研究概况 1

1.1.1当前铅污染基本情况 1

1.1.2土壤中重金属污染对生物体的危害 1

1.2植物修复技术 3

1.2.1植物对环境中重金属的防御措施 3

1.2.2传统土壤修复和植物修复技术 6

1.3桑树在植物修复中的应用 9

1.4生物炭在植物修复中的应用 10

1.5本研究的意义 12

第二章 材料与方法 13

2.1实验材料 13

2.2实验器材 13

2.3材料处理 13

2.4指标测定 14

2.4.1生物量 14

2.4.2叶绿素、光合指标 15

2.4.3活性物质含量 15

2.4.4损伤指标和铅积累 17

第三章 结果与分析 19

3.1土壤铅胁迫下生物炭对桑树生物量及根系的影响