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371.
Remediation of copper polluted red soils with clay materials 总被引:2,自引:0,他引:2
Attapulgite and montmorillonite were utilized to remediate heavy metal polluted red soils in Guixi City, Jiangxi Province, China.
The e ects of clay minerals on availability, chemical distribution, and biotoxicity of Cu and Zn were evaluated. The results provided
a reference for the rational application of clay materials to remediate heavy metal contaminated soils. From the sorption experiment,
the maximum adsorbed Cu2+ by attapulgite and montmorillonite was 1501 and 3741 mg/kg, respectively. After polluted red soil was
amended with attapulgite or montmorillonite and cultured at 30 and 60 days, soil pH increased significantly compared to the control. An
8% increase in the amount of montmorillonite in soil and 30 days incubation decreased acid exchangeable Cu by 24.7% compared to the
control red soil. Acid exchangeable Cu decreased with increasing amounts of attapulgite and montmorillonite, with best remediation
e ect reached at a dose of 8%. Results also showed that the Cu poisoning e ect on earthworms was reduced with the addition of
attapulgite and montmorillonite. Montmorillonite showed the best e ect, with the addition of a 2% dose the mortality of earthworms
decreased from 60% to zero compared to the control. Our results indicated that the bioavailability of Cu in soils was reduced more
e ectively with the application of montmorillonite than attapulgite. 相似文献
372.
This study compares the accumulation of Cr(VI) and biochemical changes (total chlorophyll, carotenoid, protein, malondialdehyde
(MDA) and cysteine contents) and roles of antioxidant enzymes (superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate
peroxidase (APX)) in tolerance to metal induced stress in Cucumis utillissimus L. grown in Cr contaminated soil (CS) with garden
soil (GS). Furthermore, Cr bioavailability was enhanced by ethylene diamine tetra-acetic acid (EDTA) addition to the soil to forecast
the plant’s accumulation pattern at elevated Cr environment. Accumulation of Cr in the leaves of the plant increased with increase in
substrate metals concentration. It further increased with the addition of EDTA by 1437% and 487% in GS and CS, respectively at the
highest treatment level. The lipid peroxidation increased proportionately with increase in Cr accumulation in the leaves. All the activity
of antioxidant enzymes (SOD, GPX and APX) and the level of cysteine increased with dose dependant manner. SOD and cysteine were
observed to be higher in the GS than in CS, but APX and GPX were found to be higher in CS than in GS. The increase in GPX and APX
activities with the increase in Cr concentration could be assumed that these two enzymes have a major role in the defense mechanism
towards stress induced by Cr in C. utillissimus. 相似文献
373.
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375.
人类利用资源的矛盾,实质上源于人类对资源需求的不断增加与自然资源的自然供给的相对有限性之间的矛盾。要解决这一矛盾,实现资源的永续利用,就是要实现资源的人类需求与自然供给之间的平衡,即:自然资源需求量≤自然资源的最大供给能力;自然资源需求量的增长速度≤技术支持下的自然资源供给能力的提高速度。 相似文献
376.
2010年,韶关市紧紧围绕创建“全国生态文明示范市”目标,采取加快经济发展方式转变、维护生态屏障、创建优美宜居乡村等措施,综合整治环境,还优美环境于民。加快经济发展方式转变大力发展生态经济,加快推进以资源高效利用和循环利用为核心、以“减量化、再利用、资源化”为原则的低消耗、低排放、高效率的经济增长模式, 相似文献
377.
378.
《资源节约和综合利用》2011,(10):4-4
9月19日,南科技部和国家发改委联合举办的碳收集领导人论坛(CSLF)第四届部长级会议在北京举行。科技部部长万钢在致辞中指出,未来十年将是决定全球CO2捕集、利用和封存(CCUS)技术发展最重要的时期,中方愿与各方一道,共同推动CO2资源化利用技术的发展。 相似文献
379.
从芒硝法(Na2SO4)氟硅酸钠生产工艺过程分析了氟硅酸钠母液废水的来源和主要成分,剖析了现有污水处理工艺过程存在的三个方面缺陷,并从实施清洁生产、节能减排和完善治理设施两方面提出了改进对策,全面实现了废水的循环利用。 相似文献
380.