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植物对重金属镉的吸收及其体内积聚特征研究

时间:2019-04-08 10:13来源:毕业论文
摘要: 土壤是人类赖以生存的基础,近年来我国土壤镉污染日益严重,威胁着人类的生活健康,镉污染的治理迫在眉睫。植物修复技术对改善重金属污染土壤有重要的实践意义。本实验

摘要: 土壤是人类赖以生存的基础,近年来我国土壤镉污染日益严重,威胁着人类的生活健康,镉污染的治理迫在眉睫。植物修复技术对改善重金属污染土壤有重要的实践意义。本实验在三种浓度的镉(5、11、22mg/kg)胁迫下进行,通过观察种子在胁迫下萌发及幼苗生理特性的情况,以及鱼腥草、杂交狼尾、芒草这三种生长成熟的草本植物对镉的吸收能力、修复潜力分析,拟比较和筛选出能在镉污染土壤中能良好生长,并对镉超标土壤有改良作用的植物。结果表明,1、在种子萌发阶段,低浓度的镉对植物种子有促进萌发的作用,相对的,高浓度的镉对植物种子有抑制萌发的作用;2、在植物成熟阶段,随着时间的推移,叶片中镉的积累速率也存在差异,在7D时,叶中镉含量增长速度较快,相比,在移栽14D之后,叶中镉含量随天数增长缓慢,在这之后至40D期间,叶片中镉含量几乎不再增加,可以认为叶片对镉的吸收逐渐趋于饱和;3、鱼腥草、杂交狼尾、芒草这三种草本富极植物对重金属镉污染土壤有一定的修复潜力,并以鱼腥草最大,杂交狼尾和芒草次之。34393
毕业论文关键词:镉(Cd);土壤污染;重金属;植物修复    
Study on the accumulation characters and absorb on Cd of common plants
Abstract: Soil is the basis of human survival ,in recent years, Soil Cd contaminated is increasingly serious, threating human’s health , cadmium pollution control is extremely urgent.Phytoremediation technology has important practice significance to improve the contaminated soil. The experiment examined the effect of cadmium stress on seed germination and  physiological characteristics of seedling, planting three kind of plants under three concentrations of cadmium (5.5 / 11/22 mg / kg) stress, analyzing their ability to absorb heavy metals cadmium and the repair potential. Comparing and selecting some plants which can be well growing and having progressive effect on cadmium pollution soil based on theory by experiment. The results showed that,1, low concentrations of cadmium on the germination of plant seeds to promote the seed germination ,high concentration of cadmium could inhibit the seeds germination; 2, As time goes, leaves had different cadmium accumulation rate, in the 7D, the cadmium content in leaves grow faster than the 14D, the cadmium content in leaves of slow growth with the number of days in the period to 40D, after that cadmium content in leaves almost no increase, it is believed to absorb cadmium leaves gradually become saturated; 3, Herbaceous plant has some repair potential to the cadmium contaminated soil ,the effect on Houttuynia is better than Hybrid wolf tail and Miscanthus . 源自$六l维,论:文w网)加7位QQ3249^114 www.lwfree.cn
Keywords: Cadmium (Cd);Soil pollution; Heavy metals;Phytoremediation
目录
摘要    2
Abstract    3
目录    4
1 绪论    5
1.1土壤镉污染的现状与危害    5
1.1.1镉污染的现状    5
1.1.2镉污染的危害    5
1.2镉污染的背景值测定    6
1.3存在的问题    6
1.4植物修复技术基本概念    7
1.5超富极植物概念以及衡量标准    7
1.6国内外修复镉研究进展    8
1.7本研究问题的提出与意义    9
2 材料与方法    10
2.1实验材料介绍    10
2.1.1种子材料    10
2.1.2移植材料    10
2.2实验材料的处理与培养    12
2.2.1种子培养皿培育、阶梯浓度镉胁迫处理    12
2.2.2三种植物盆栽移植,阶梯浓度镉胁迫处理    12
2.3种子活力的测定    12 植物对重金属镉的吸收及其体内积聚特征研究:http://www.lwfree.cn/shengwu/20190408/31875.html
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