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211.
分别于2014年10月,2015年1、3、5月采集重庆南山老龙洞地下河出口的水样,过滤取水悬浮物质,采用气相色谱-质谱联用仪(GC-MS)定量分析悬浮物中甾类物质的成分与质量浓度;利用多指标综合分析对南山老龙洞地下河粪便污染进行判断并追溯粪便污染物的主要来源.结果表明,样品中共测出10种甾类物质,其中包括9种醇类和1种酮类.总甾类物质的质量浓度为1 573~5 007 ng·L-1,且3、5月均大于10、1月.虽然各月间地下河的组成存在差异,但以胆固醇、β-谷甾醇和粪醇为主要成分,三者的质量浓度之和占总甾类的50.8%~80.4%.另外,(差向异构粪醇+粪醇)/(粪醇+差向异构粪醇+二氢胆固醇)的值均大于0.7,指示各月均受到粪便污染;10月差向异构粪醇/粪醇的值小于0.2,指示污水主要来自上游污水处理厂;1、3、5月的粪醇/ΣSteroids、粪醇/24-乙基粪醇的值分别为0.109~0.254、6.3~10.3,指示地下河主要受到人类粪便的影响;3月的24-乙基粪醇/24-乙基胆甾烷醇为0.86,小于1月的5.4和5月的2.3,说明该月地下河受家禽类动物粪便的影响较1月和5月严重. 相似文献
212.
湖北省某钢铁厂工业区及周边铅污染调查 总被引:2,自引:0,他引:2
为了解湖北省某钢铁厂周边铅污染的现状,通过对钢铁厂工业区及其周边乡村的土壤、蔬菜、居民体内和排污渠污泥中铅元素含量的研究,其结果表明:钢铁厂周围的土壤、蔬菜、居民均受到了一定程度的铅等重金属元素的污染,其含量高于国家标准或正常范围;钢铁厂工业区周边土壤铅污染主要由于工业废气(烟尘)扩散沉降和废水灌溉引起;污染区人体尿样中铅元素含量(116~160 ng/mL)普遍超标,头发样(2.09~12.04 μg/g)基本正常,尿样比头发样更能显示铅等重金属元素在人体内的分布特征. 相似文献
213.
大宝山矿区水体中重金属的行为研究 总被引:4,自引:0,他引:4
广东大宝山矿区矿山废水的排放使周边生态环境遭受了严重的破坏。水体中重金属Cu、Zn、Cd和Pb的溶解态浓度分别达到13.82、50.83、0.103和2.91 mg.L-1。Cu、Zn、Cd和Pb的溶解态和悬浮态含量沿河流主干道断面呈相似的空间分布规律,上游都是沿水流方向降低,下游因吸附于悬浮物中的重金属重新释放略有增加。悬浮物中重金属元素的化学形态提取和扫描电镜能谱分析(SEM/EDAX)表明:4种重金属元素都以残渣态为主要存在形态,其次为可还原态,个别断面的Cd可还原态甚至超过了残渣态的含量,说明该水体这4种元素对环境都有一定的潜在威胁性。 相似文献
214.
明确了建设用地土壤污染状况调查监管的对象,分析了我国现阶段调查监管存在的监管力量不足、从业门槛不明确、实时监管措施缺乏等问题.结合国内外调查工作监管经验和近年苏州工业园区调查监管的探索实践,提出了鼓励引导相关利益方参与调查监管、建立健全从业人员和机构监管制度、引入监理机制、推进信息化过程管理等对策建议. 相似文献
215.
Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China 总被引:24,自引:0,他引:24
Khan S Cao Q Zheng YM Huang YZ Zhu YG 《Environmental pollution (Barking, Essex : 1987)》2008,152(3):686-692
Consumption of food crops contaminated with heavy metals is a major food chain route for human exposure. We studied the health risks of heavy metals in contaminated food crops irrigated with wastewater. Results indicate that there is a substantial buildup of heavy metals in wastewater-irrigated soils, collected from Beijing, China. Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher (P相似文献
216.
Holtze MS Sørensen SR Sørensen J Aamand J 《Environmental pollution (Barking, Essex : 1987)》2008,154(2):155-168
The benzonitriles dichlobenil, bromoxynil and ioxynil are important broad-spectrum or selective herbicides used in agriculture, orchards and public areas worldwide. The dichlobenil metabolite 2,6-dichlorobenzamide is the most frequently encountered groundwater contaminant in Denmark, which suggests that the environmental fate of these three structurally related benzonitrile herbicides should be addressed in detail. This review summarises the current knowledge on microbial degradation of dichlobenil, bromoxynil and ioxynil with particular focus on common features of degradation rates and pathways, accumulation of persistent metabolites and diversity of the involved degrader organisms. 相似文献
217.
重金属污染土壤接种丛枝菌根真菌对蚕豆毒性的影响 总被引:6,自引:1,他引:5
采用盆栽实验的方法,研究了重金属(包括Cu、Zn、Pb和Cd)复合污染和接种丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)Glomus mosseae对蚕豆(Vicia faba)生长及DNA损伤的影响.结果表明,虽然接种菌根真菌对蚕豆生物量的影响并不显著,但是却显著影响植物对重金属的吸收,接种菌根真菌对蚕豆吸收4种重金属元素的作用有差异.采用单细胞凝胶电泳(single cell gel electrophoresis,SCGE)法研究接种菌根真菌对蚕豆叶片的DNA损伤的影响,与重金属吸收的结果相吻合.结果表明,接种处理可显著增加蚕豆叶片的DNA损伤程度,这与接种处理可提高植物的重金属吸收相一致. 相似文献
218.
Spatial and temporal patterns of metal mobilisation from former water-powered, Pb working sites in a suburban area of Sheffield (UK) were investigated. Twelve time-integrated mass flux samplers were strategically deployed over two contrasting campaign periods (summer and winter). Suspended sediment samples were characterised magnetically and subjected to metal analysis. Metal levels in the upper River Sheaf showed a marked spatial and temporal variability. Pb concentrations in particular were relatively high (maximum 2132 mg kg(-1)). Their distribution tended to reflect the historical contamination of the valley by 17th to 19th century industry, especially during summer high discharge conditions. The mean suspended sediment Pb concentration (803 mg kg(-1)) exceeds contamination guidelines. It is unclear whether ground remediation of one of the seven floodplain sites in the catchment has been successful. The river is still affected by the legacy of at least two other Pb working sites. 相似文献
219.
Jacobsen CS van der Keur P Iversen BV Rosenberg P Barlebo HC Torp S Vosgerau H Juhler RK Ernstsen V Rasmussen J Brinch UC Jacobsen OH 《Environmental pollution (Barking, Essex : 1987)》2008,156(3):794-802
Pesticide mineralization and sorption were determined in 75 soil samples from 15 individually drilled holes through the vadose zone along a 28 km long transect of the Danish outwash plain. Mineralization of the phenoxyacetic acid herbicide MCPA was high both in topsoils and in most subsoils, while metribuzine and methyltriazine-amine was always low. Organic matter and soil pH was shown to be responsible for sorption of MCPA and metribuzine in the topsoils. The sorption of methyltriazine-amine in topsoil was positively correlated with clay and negatively correlated with the pH of the soil. Sorption of glyphosate was tested also high in the subsoils. One-dimensional MACRO modeling of the concentration of MCPA, metribuzine and methyltriazine-amine at 2 m depth calculated that the average concentration of MCPA and methyltriazine-amine in the groundwater was below the administrative limit of 0.1 μg/l in all tested profiles while metribuzine always exceeded the 0.1 μg/l threshold value. 相似文献
220.
Paz-Alberto AM Sigua GC Baui BG Prudente JA 《Environmental science and pollution research international》2007,14(7):498-504
Background, Aims and Scope The global problem concerning contamination of the environment as a consequence of human activities is increasing. Most of
the environmental contaminants are chemical by-products and heavy metals such as lead (Pb). Lead released into the environment
makes its way into the air, soil and water. Lead contributes to a variety of health effects such as decline in mental, cognitive
and physical health of the individual. An alternative way of reducing Pb concentration from the soil is through phytoremediation.
Phytoremediation is an alternative method that uses plants to clean up a contaminated area. The objectives of this study were:
(1) to determine the survival rate and vegetative characteristics of three grass species such as vetivergrass, cogongrass
and carabaograss grown in soils with different Pb levels; and (2) to determine and compare the ability of the three grass
species as potential phytoremediators in terms of Pb accumulation by plants.
Methods The three test plants: vetivergrass (Vetiveria zizanioides L.); cogongrass (Imperata cylindrica L.); and carabaograss (Paspalum conjugatum L.) were grown in individual plastic bags containing soils with 75 mg kg−1 (37.5 kg ha−1) and 150 mg kg−1 (75 kg ha−1) of Pb, respectively. The Pb contents of the test plants and the soil were analyzed before and after experimental treatments
using an atomic absorption spectrophotometer. This study was laid out following a 3 × 2 factorial experiment in a completely
randomized design.
Results On the vegetative characteristics of the test plants, vetivergrass registered the highest whole plant dry matter weight (33.85–39.39
Mg ha−1). Carabaograss had the lowest herbage mass production of 4.12 Mg ha−1 and 5.72 Mg ha−1 from soils added with 75 and 150 mg Pb kg−1, respectively. Vetivergrass also had the highest percent plant survival which meant it best tolerated the Pb contamination
in soils. Vetivergrass registered the highest rate of Pb absorption (10.16 ± 2.81 mg kg−1). This was followed by cogongrass (2.34 ± 0.52 mg kg−1) and carabaograss with a mean Pb level of 0.49 ± 0.56 mg kg−1. Levels of Pb among the three grasses (shoots + roots) did not vary significantly with the amount of Pb added (75 and 150
mg kg−1) to the soil.
Discussion Vetivergrass yielded the highest biomass; it also has the greatest amount of Pb absorbed (roots + shoots). This can be attributed
to the highly extensive root system of vetivergrass with the presence of an enormous amount of root hairs. Extensive root
system denotes more contact to nutrients in soils, therefore more likelihood of nutrient absorption and Pb uptake. The efficiency
of plants as phytoremediators could be correlated with the plants’ total biomass. This implies that the higher the biomass,
the greater the Pb uptake. Plants characteristically exhibit remarkable capacity to absorb what they need and exclude what
they do not need. Some plants utilize exclusion mechanisms, where there is a reduced uptake by the roots or a restricted transport
of the metals from root to shoots. Combination of high metal accumulation and high biomass production results in the most
metal removal from the soil.
Conclusions The present study indicated that vetivergrass possessed many beneficial characteristics to uptake Pb from contaminated soil.
It was the most tolerant and could grow in soil contaminated with high Pb concentration. Cogongrass and carabaograss are also
potential phytoremediators since they can absorb small amount of Pb in soils, although cogongrass is more tolerant to Pb-contaminated
soil compared with carabaograss. The important implication of our findings is that vetivergrass can be used for phytoextraction
on sites contaminated with high levels of heavy metals; particularly Pb.
Recommendations and Perspectives High levels of Pb in localized areas are still a concern especially in urban areas with high levels of traffic, near Pb smelters,
battery plants, or industrial facilities that burn fuel ending up in water and soils. The grasses used in the study, and particularly
vetivergrass, can be used to phytoremediate urban soil with various contaminations by planting these grasses in lawns and
public parks.
ESS-Submission Editor: Dr. Willie Peijnenburg (wjgm.peijnenburg@rivm.nl) 相似文献