玉米对有机氯农药污染土壤的修复潜力(英文)

[目的]确定玉米对土壤中老化滴滴涕和六六六的累积、迁移和转化能力。[方法]温室盆栽试验。取均匀掺入梯度浓度滴滴涕和六六六农药的科研土壤装盆,收集持续盆栽过程中不同时段的土壤和植物样品进行残留测试。[结果]所选择的玉米植株在所设计的土壤污染浓度范围内具有宽域的滴滴涕和六氯环己烷清除能力,其茎秆、根系的生物浓缩系数分别介于0.004至0.027和0.036到0.097之间,但去除率均低于0.1,滴滴涕和六六六梯度处理间无显著差异。滴滴涕可通过被动吸附和主动吸收被玉米植体积累,且由还原性脱卤化介导,p,p’-DDT向p,p’-DDE转化。[结论]玉米对土壤有机氯农药具有清除修复能力,且有机氯农药的对玉米脂肪的亲和力是影响其在植物体内的吸收和转运的主要因素之一。     

Enhanced dissipation of chrysene in planted soil: the impact of a rhizobial inoculum

Results from an innovative approach to improve remediation in the rhizosphere by encouraging healthy plant growth and thus enhancing microbial activity are reported. Mixed grass-legume systems, together with microbial inoculants, were used to remediate a polycyclic aromatic hydrocarbon (chrysene) spiked agricultural soil. Inoculants were symbiotic rhizobia, which may play an important role in rhizoremediation by increasing plant and root growth. An inoculum of an isolate of Rhizobium leguminosarum bv. trifolii, selected for PAH tolerance, was produced using a peat carrier. The inoculum and white clover (Trifolium repens L.), were planted into soils with ryegrass (Lolium perenne L.). The soils spiked with chrysene (500 mg kg⁻¹) then aged for 4 weeks. Shoot- and root-biomass of plants, and the amount of root nodulation, were determined. Rhizobial populations, soil pH and soil nitrogen were also monitored throughout the trial. In addition, the ability of the inoculated rhizobial strain to utilise chrysene as a sole carbon source was assessed. Direct uptake and/or degradation of chrysene by the clover and ryegrass did not occur to a significant degree. Enhanced losses of chrysene were seen in planted, non-sterile soils that contained a rhizobial inoculum. No direct degradation of chrysene by R. leguminosarum bv. trifolii was observed and no enhanced losses of PAHs were detected in sterile soils after inoculation with rhizobia. Results suggest that the enhanced dissipation of chrysene, observed in the non-sterile planted inoculated pots, was not a result of degradation of chrysene by R. leguminosarum bv. trifolii. The symbiotic association with R. leguminosarum bv. trifolii improved plant vigour and growth in inoculated planted treatments. This may have stimulated the rhizospheric microflora to degrade chrysene.     

Biotransformation of pentachlorophenol by Chinese chive and a recombinant derivative of its rhizosphere-competent microorganism, Pseudomonas gladioli M-2196

The use of plants or microorganisms to detoxify contaminated soil or groundwater is a potentially cost-effective alternative to traditional remediation technologies. This study investigated the effects of a rhizosphere microbe on the biotransformation of pentachlorophenol (PCP). Chinese chive (Allium tuberosum Rottler) and its rhizosphere-competent bacterium, Pseudomonas gladioli M-2196, were used as a plant-bacterium pair. The genes encoding PCP-degrading enzymes from Sphingobium chlorophenolicum ATCC39723 were introduced into the chromosome of P. gladioli M-2196. The resultant transformants were able to degrade PCP almost completely in liquid medium within 4 d in culture. PCP degradation experiments showed that the amount of PCP in soil (3.3 μg g⁻¹) planted with the P. gladioli transformant (T-9) and Chinese chive decreased by 40% as compared with untreated soil (control) by day 28. Strain T-9, which was used in the PCP degradation experiments, retained the ability to colonize the Chinese chive rhizosphere after 28 d. Tetrachlorocatechol (TCC) was detected as a metabolite of PCP in Chinese chive extract. The amount of PCP in soil treated only with Chinese chive decreased by 30% as compared with the control, but the total amount of PCP plus TCC detected in the plant was less than 10% of the amount of PCP removed from soil. This might be due to the enhancement of a soil microflora population capable of degrading PCP by root exudates from Chinese chive. Therefore, Chinese chive itself, in addition to the rhizosphere-competent bacterium, seemed to play an important role in reducing the PCP level in the soil.     

植物修复技术在城市园林中的应用

植物修复作为一种有潜力、正在发展的清除环境污染的绿色技术,在城市环境土壤改良、水质改善以及空气污染物的清除等方面发挥着越来越大的作用,在园林绿化等实际工作中有着广阔的应用前景。     

有机污染物污染土壤的植物修复

综述了植物修复土壤有机污染物污染的机理及应用等的研究进展状况,提出了未来植物修复的研究重点。     

花卉修复污染环境的研究现状及发展潜力

近年来,污染环境植物修复技术是指利用绿色植物从环境中吸收带走重金属或将其无害化而达到治理目的的方法。花卉修复属于植物修复范畴,是目前发展最快的环境友好、经济、高效的治理技术,也是当前国内外研究的热点。在综述花卉修复技术的概念、类型和优点的基础上,详细论述了花卉植物修复污染环境的作用原理和研究现状,并对其发展潜力进行了分析。     

植物冶金的研究进展

介绍植物冶金的概念和基本方法,综述植物冶金的研究现状和已经取得的一些研究成果,分析植物冶金可行的经济模型,并总结植物冶金的优点和局限性,认为植物冶金是一种极具发展潜力的新型绿色冶金技术。     

The significant contribution of mycorrhizal fungi and earthworms to maize protection and phytoremediation in Cd-polluted soils

Mycorrhizal fungi and earthworms can individually or interactively influence plant growth and heavy metal uptake. The influence of earthworms and arbuscular mycorrhizal (AM) fungi either alone or in combination on maize (Zea mays L.) growth and cadmium (Cd) uptake was investigated in a calcareous soil artificially spiked with Cd. Soils were contaminated with Cd (10 and 20 mg Cd kg⁻¹), inoculated or un-inoculated with the epigeic earthworm Lumbricus rubellus and two AM fungal species (Rhizophagus irregularis and Funneliformis mosseae) for two months of growth under greenhouse conditions. Generally, earthworms alone increased both shoot P uptake and biomass but decreased shoot Cd concentration and root Cd uptake. AM fungi individually often increased total maize P uptake, declined shoot Cd concentration, and consequently produced higher total biomass. However, R. irregularis enhanced shoot Cd uptake at low Cd level and root Cd uptake at high Cd level. In plants inoculated with F. mosseae species, earthworms increased shoot biomass and Cd uptake, decreased root biomass and Cd uptake at all Cd levels, and increased shoot Cd concentration at low Cd level. In plants colonized by R. irregularis species, however, earthworm addition decreased maize biomass only at high Cd level and root Cd concentration and total maize Cd uptake at both Cd levels. Earthworm activity decreased Cd transfer from the soil to maize roots at low Cd level, but this was counterbalanced in the presence of F. mosseae. Mycorrhizal symbiosis significantly reduced the transfer of Cd from roots to shoots, independence of earthworm effect. Overall, it is concluded that L. rubellus and AM fungi, in particular F. mosseae isolate, improved maize tolerance to Cd toxicity both individually and interactively by increasing plant growth and P nutrition, and restricting Cd transfer to the aboveground biomass. Consequently, the single and interactive effects of the two soil organisms might potentially be important not only in protecting maize plants against Cd toxicity, but also in Cd phytostabilization in soils polluted by this highly toxic metal.     

植物激素处理对向日葵富集133Cs的影响

[目的]探寻高效修复~(133)Cs污染的技术手段。[方法]通过土壤盆栽试验,研究生长素(IAA)、赤霉素(GA)、水扬酸(SA)3种植物激素对超富集植物向日葵吸收和积累~(133)Cs的影响。[结果]~(133)Cs胁迫下,施用植物激素能显著增加向日葵对~(133)Cs的吸收、转运、积累富集。与茎和根相比,叶、花为主要富集~(133)Cs的器官。3种激素作用下的单株累积量总体表现为SAGAIAA。[结论]500 mg/L SA处理下,向日葵对~(133)Cs的吸收量、转运系数、富集系数达到最大值。     

植物激素处理对向日葵富集133Cs的影响

[目的]探寻高效修复133Cs污染的技术手段.[方法]通过土壤盆栽试验,研究3种植物激素对超富集植物向日葵吸收和积累133Cs的影响.[结果]133Cs胁迫下,施用植物激素能显著增加向日葵对133Cs的吸收、转运、积累富集.叶、花为主要富集133Cs的器官.3种激素作用下的单株累积量总体表现为SA＞GA＞IAA.[结论]100 mg/LSA处理下,向日葵对133Cs的吸收量、转运、富集系数达到最大值.