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51.
Enhanced 1,2-dichloroethane degradation in heavy metal co-contaminated wastewater undergoing biostimulation and bioaugmentation 总被引:1,自引:0,他引:1
Biostimulation, bioaugmentation and dual-bioaugmentation strategies were investigated in this study for efficient bioremediation of water co-contaminated with 1,2-dichloroethane (1,2-DCA) and heavy metals, in a microcosm set-up. 1,2-DCA concentration was periodically measured in the microcosms by gas chromatographic analysis of the headspace samples, while bacterial population and diversity were determined by standard plate count technique and Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR–DGGE) analysis, respectively. Dual-bioaugmentation, proved to be most effective exhibiting 22.43%, 26.54%, 19.58% and 30.49% increase in 1,2-DCA degradation in microcosms co-contaminated with As3+, Cd2+, Hg2+ and Pb2+, respectively, followed by bioaugmentation and biostimulation. Dual-bioaugmented microcosms also exhibited the highest increase in the biodegradation rate constant (k1) resulting in 1.76-, 2-, 1.7- and 2.1-fold increase in As3+, Cd2+, Hg2+ and Pb2+ co-contaminated microcosms respectively, compared to the untreated microcosms. Dominant bacterial strains obtained from the co-contaminated microcosms were found to belong to the genera Burkholderia, Pseudomonas, Bacillus, Enterobacter and Bradyrhizobium, previously reported for 1,2-DCA and other chlorinated compounds degradation. PCR–DGGE analysis revealed variation in microbial diversity over time in the different co-contaminated microcosms. Results obtained in this study have significant implications for developing innovative bioremediation strategies for treating water co-contaminated with chlorinated organics and heavy metals. 相似文献
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摘要重金属废水对环境的污染已经引起科研人员的广泛关注。以粉煤灰和水泥为原料、添加活性成分FeS,制备一种免烧陶粒用于含重金属Cu2+、Zn2+、Pb2+的废水处理。探讨了物料配比及蒸养时间对陶粒筒压强度及其比表面积的影响;研究了固液比、接触时间、pH、温度及初始溶液浓度等因素对Cu2+、Zn2+、Pb2+离子净化效果的影响规律,并对实验结果进行了等温线拟合。XRD分析显示,免烧陶粒中存在Ca(OH)2、C—D—H、FeS等矿物相,对重金属离子具有非常好的固定化作用。该免烧陶粒对重金属离子具有很好的去除效果,具备较好的应用前景。 相似文献
54.
Szlinder-Richert J Usydus Z Malesa-Ciećwierz M Polak-Juszczak L Ruczyńska W 《Chemosphere》2011,85(11):1725-1733
Chemical analyses were performed in nine fish species that are popular on the Polish market. These included Baltic fish (cod, herring, salmon), fish farmed in Poland (carp, trout), marine fish imported from China (Alaska pollock, sole), and farmed fish imported from Vietnam and China (sutchi catfish, tilapia). The nutritional composition (amino acid, micro- and macronutrients, fat-soluble vitamins - A1, D3, E) and certain contaminants (organochlorine pesticides, OCPs; indicator polychlorinated biphenyl, PCB6; polychlorinated dibenzo-paradioxins and polychlorinated dibenzofurans, PCDD/Fs; dioxin-like polychlorinated biphenyls, dl-PCBs; organotin compounds, OCTs; dyes, malachite green and crystal violet; veterinary drug residues, nitrofurans and chloramphenicol; toxic metals, Cd, Pb, Hg) in the muscle tissues of fish were determined. It was confirmed that the fish species analyzed were excellent sources of amino acids, and were rich in phosphorous and selenium. Baltic Sea fish (salmon, herring), fish farmed in Poland (carp and trout), and tilapia were also rich in vitamin D3.Traces of OCP, PCB6, OCT, dyes, veterinary drug residues, and heavy metals were detected in concentrations which do not pose a threat to consumers at the current rate of fish consumption in Poland. However, the problem might arise from the content of PCDD/Fs and dl-PCBs in fatty Baltic fish. The fish species analyzed, differed in their nutritional values and degrees of contamination. We suggest that for optimum health and safety, it is advisable that consumers include a variety of different fish species in their diets. 相似文献
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生活垃圾填埋场封场后种植植物中重金属迁移研究 总被引:3,自引:1,他引:3
在上海老港生活垃圾填埋场填埋单元封场的覆盖土中掺混了矿化垃圾种植植物,分析Cd、Pb、Cu、Zn 4种重金属在土壤和植物中的迁移变化,研究表明:(1)覆盖土土质从一般耕作土变成肥沃土壤;覆盖土和种植混合土重金属Cd、Pb、Cu、Zn中Cd、Pb含量相近,但种植土的Cu含量略大于覆盖原土,Zn含量远大于覆盖原土;(2)植物能富集土壤和垃圾中的重金属,木本植物的根部富集重金属的能力强于草本植物,但重金属在草本植物根、茎、叶中的迁移速度大于木本植物;(3)植物根、茎、叶的Cu、Zn含量均远大于未受污染土壤种植植物相应部位的Cu、Zn含量,种植的植物不能供家养动物食用,以免通过食物链作用危及人体安全. 相似文献
57.
雷州半岛土壤重金属分布特征及其污染评价 总被引:5,自引:1,他引:5
在雷州半岛采集了106个土壤表层样品,分析了其中8种重金属元素(Cu、Pb、Zn、Cr、Ni、Cd、Hg和As)的全量.结果表明,雷州半岛土壤重金属污染由高到低排序为Ni>Cr>Hg>Cu>Zn>Cd>As>Pb,Zn、Cd、As和Pb质量浓度均没有超标,Hg和Cu质量浓度超标率亦不高,但Ni和Cr平均质量浓度达49.81、87.13 mg/kg,高于国内外其他对照区域,超标率分别为25.47%和24.53%;重金属元素在雷州半岛各土壤利用类型中分布规律不明显,按4种主要土壤利用类型受重金属污染程度大小排序为甘蔗地>果园土>水田>菜地;雷州半岛土壤综合污染指数总平均为0.970,土壤总体上尚清洁,重金属污染处于警戒水平;雷州半岛各区域中,徐闻、雷州两地土壤重金属质量浓度明显高于其他地区,其主要原因是徐闻、雷州两地成土母质主要为玄武岩,造成土壤Cr、Ni及其他重金属背景值较高. 相似文献
58.
三峡水库135 m蓄水前后水体重金属环境健康风险评价 总被引:4,自引:0,他引:4
三峡水库135 m蓄水后,水体中各重金属的单因子污染指数和Nemerow综合污染指数均有不同程度的增大,特别是Pb污染应该引起重视.健康风险评价结果表明,成库前后非致癌有毒化学物质(Hg、Pb和Cu)所引起的健康危害的个人年风险为Pb>Cu>Hg,致癌物质对人体健康危害的个人年风险均大于非致癌物.各类污染物所致个人平均健康危害成库前后均低于国际辐射防护委员会(ICRP)推荐的标准,为可接受水平. 相似文献
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60.
Belias CV Bikas VG Dassenakis MJ Scoullos MJ 《Environmental science and pollution research international》2003,10(5):287-295
GOAL, SCOPE AND BACKGROUND: Over the last decade Greece has become a leading country in the EU as concerns the cage farming of seabream and seabass. A strong debate has risen, however, about the environmental impacts of aquacultures in the coastal areas. The present paper deals with this problem and it is based on measurements of physico-chemical parameters in the water column, particulate matter and sediments in the area of Astakos Gulf, a coastal embayment in western Greece where three big fish farms are currently operating. METHODS: Water samples were collected by using Hydro-Bios sampling bottles, whereas a prototype sediment trap was installed under a fish cage for the collection of particulate matter. Temperature, dissolved oxygen, pH and salinity were measured in situ using portable equipment. Nutrients were determined by standard spectrophotometric methods. Trace metals were determined by Atomic Absorption Spectrometry. Dissolved organic carbon was determined by a Shimadzu 5000A carbon analyzer, whereas organic carbon in sediments was determined titrimetrically. RESULTS AND DISCUSSION: No clear eutrophication incidents have been identified, although the water column near the fish farms was enriched in nutrients and organic carbon. A sludge 'blanket' covers considerable parts of the seabed and is enriched in colloidal organic carbon and trace metals (Cd, Cu, Fe and Zn) that come from unused fish food. The biodegradation of this sludge leads to the development of anoxic conditions followed by the formation of undesirable gases, precipitation or remobilization of metals and the extinction of benthic fauna. CONCLUSION: The operation of fish farms at the coastal area of Astakos Gulf, and probably in similar Mediterranean gulfs, affects the marine environment, particularly in the vicinity of the cages. The most significant influence concerns the near-bottom water layer. The environmental impacts depend on the amount of food given to fishes, the mode of feeding, the fish density in cages, the annual production and the years of unit operation. The hydrology and the geomorphology of the area are also critical factors for its environmental quality. RECOMMENDATION AND OUTLOOK: The success of the fish-farming sector in the Mediterranean is accompanied by environmental and, in some extents, by social and marketing problems. These problems, derived from the rapid development of fish farming, can be solved only through an integrated management, using methods such as environmental impact assessment, risk assessment, economic evaluation, vulnerability assessments, resource accounting, cost-benefit analysis and outcome-based monitoring. 相似文献