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1.
Bunge Michael Khknen Mika A. Rmisch Winfried Opel Matthias Vogler Susanne Walkow Fred Salkinoja-Salonen Mirja Lechner Ute 《Environmental science and pollution research international》2007,14(1):3-10
Background, Aims and Scope Sediments of the Spittelwasser creek are highly polluted with organic compounds and heavy metals due to the discharge of untreated
waste waters from the industrial region of Bitterfeld-Wolfen, Germany over the course of more than one century. However, relatively
few data have been published about the chloroorganic contamination of the sediment. This paper reports on the content of different
(chloro)organic compounds with special emphasis on polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F), and chlorobenzenes. Existing concepts for the remediation of Spittelwasser sediment include
the investigation of natural attenuation processes, which largely depend on the presence of an intact microbial food web.
In order to gain more insight in terms of biological activity, we analyzed the capacity of sediment microflora to degrade
organic matter by measuring the activities of extracellular hydrolytic enzymes involved in the biogeochemical cycling of carbon,
nitrogen, phosphorus and sulfur. Furthermore, the detection of physiologically active bacteria in the sediment, particularly
of those known for their capability to reductively dehalogenate organochlorine compounds, illustrates the potential for intrinsic
bioremediation processes.
Methods PCDD/F and chlorobenzenes were analyzed by gas chromatography(GC)/mass spectrometry and GC/flame ionization detection, respectively.
The activities of hydrolytic enzymes were determined from freshly sampled sediment layers using 4-methylumbelliferyl (MUF)
or 7-amino-4-methylcoumarin-conjugated model compounds and kinetic fluorescence measurements. Physiologically active bacteria
from different sediment layers were microscopically visualized by fluorescence in situ hybridization (FISH). Specific bacteria were identified by 16S rRNA gene amplification and sequencing.
Results and Discussion The PCDD/F congener profile was dominated by dibenzofurans. In addition, the presence of specific tetra and pentachlorinated
dibenzofurans supported the assumption that extensive magnesium production was one possible source for the high contamination.
A range of other chloroorganic compounds, including several isomers of chlorobenzenes, hexachlorocyclohexane and 1,1,1-trichloro-2,2-bis
(p-chloro-phenyl)ethane (DDT), was present in the sediment. Activities of extracellular hydrolytic enzymes showed a strong
decrease in those sediment layers that were characterized by high contents of absorbable organic halogen (AOX), indicating
disturbed organic matter decay. Interestingly, an abnormal increase of cellulolytic enzyme activities below the organochlorine-rich
layers was observed, possibly caused by residual cellulose from discharges of sulfite pulping wastes. FISH revealed physiologically
active bacteria in most sediment layers from the surface down to the depth of about 60 cm, including members of Desulfitobacterium (D.) and Sulfurospirillum. The presence of D. dehalogenans was confirmed by its partial 16S rRNA gene sequence.
Conclusions Results of chemical sediment analyses demonstrated high loads of organochlorine compounds, particularly of PCDD/F. Several
years after stopping the waste water discharge to Spittelwasser creek, this sediment remains a main source for pollution of
the downstream river system by way of the ongoing mobilization of sediment during high floods. As indicated by our enzyme
activity measurements, the decomposition potential for organic matter is low in organochlorine-rich sediment layers. In contrast,
the comparably higher enzyme activities in less organochlorine-polluted sediment layers as well as the presence of physiologically
active bacteria suggest a considerable potential for natural attenuation.
Recommendations and Perspectives From our data we strongly recommend to explore the degradative capacity of sediment microorganisms and the limits for in situ activity towards specific sediment pollutants in more detail. This will give a sound basis for the integration of bioremediation
approaches into general concepts to reduce the risk that permanently radiates from this highly contaminated sediment.
Submission Editor: Dr. Henner Hollert (Henner.Hollert@urz.uniheidelberg.de) 相似文献
2.
国际海事组织目前正在对《MARPOL73/78公约》附则Ⅱ-控制散装液体有毒物质污染规则作重大修改,内容包手胡毒液体物质和化学品,这很可能对主管机关、船公司和化工界造成严重的冲击。 相似文献
3.
Chemical process simulation (CPS) software has been widely used by chemical (process) engineers to design, test, optimise, and integrate process plants. It is expected that industrial ecologists to bring these same problem-solving benefits to the design and operation of industrial ecosystems can use CPS. This paper provides industrial ecology researchers and practitioners with an introduction to CPS and an overview of chemical engineering design principles. The paper highlights recent research showing that CPS can be used to model industrial ecosystems, and discusses the benefits of using CPS to address some of the technical challenges facing companies participating in an industrial ecosystem. CPS can be used to (i) quantitatively evaluate and compare the potential environmental and financial benefits of material and energy linkages; (ii) solve general design, retrofit, or operational problems; (iii) help to identify complex and often counter-intuitive solutions; and (iv) evaluate what-if scenarios. CPS should be a useful addition to the industrial ecology toolbox. 相似文献
4.
安徽月山地区是长江中下游地区的重要成岩-成矿区段。本文通过岩石学、岩石化学和同位素地球化学等方面的研究,探讨和阐明了月山地区闪长岩类的形成环境、物质来源、源区特征、岩浆形成与演化机理等。 相似文献
5.
6.
从动力地质作用原理探讨沙漠化成因 总被引:2,自引:0,他引:2
大规模沙漠化从岩石记录中可以追溯到中生代中期,第四纪以来南北两半球各存在一条中纬度沙漠带,中国的沙漠化是这个全球沙漠化进程的一个组成部分。沙漠化是在地质演化过程中受内、外动力地质作用联合控制的地质事件。是岩石圈与大气圈、生物圈及水圈强烈作用在地壳表层形成的一种特殊地质现象。这种现象的形成与演化是漫长的和具有周期性的,不会因为局部的条件变化而发生整体意义上的突变。人类活动是局部的,在整个地球沙漠化进程中只是起到一个加速剂的作用。沙漠化过程可分为3个阶段,即物理风化与沙源积聚阶段、风沙作用阶段和沙漠化阶段。沙漠期后沙丘沙经过固化生草、胶结成岩阶段后即形成风成砂岩。 相似文献
7.
全球环境变化给发展中国家和南北关系带来深刻影响,理解环境问题的全球不平等需要以发展中国家80年代开始的经济结构调整和沉重债务为背景。南方的环境政策优先在很大程度上与其生活的可持续性相连,而不是通常与全球环境变化的长期性风险相关,然而,全球环境变化又与发展中国家贫困人口的日常生活紧密相关。从南方的立场看,当“问题”对他们不十分迫切时,就很难同意采取措施,仅此原因,北方对全球环境变化的关切要得到成功回应,真正的全球契约就需要解决基本“发展”问题,主要是贫困。 相似文献
8.
针对鱼油工业废水排放特点及处理技术难点,结合实例,采用混凝、破乳进行物化预处理;采用A/O生化处理技术,提出合适的工艺流程。 相似文献
9.
提出生物作用强化城市污水一级处理工艺 ,探讨利用生物絮凝吸附作用独立承担城市污水处理任务的可行性、影响因素及运行参数。试验证明 ,处理城市污水 ,当HRT为 1 1h ,DO为 1 0mg L ,CODCr污泥负荷为 3 4~ 4 0kg kg·d时 ,CODCr、BOD5和SS去除率分别为 6 8%~ 78%、6 5 %~ 72 %和 75 %~ 85 %。 相似文献
10.
从二(?)(?)类化合物的结构、来源、毒性等简要说明对其监测的必要性,且从仪器监测(包括气相色谱、气质联用、串联质谱等)和生物监测(包括利用指示生物、生物标志物等)概述了80年代以来国内外对二(?)(?)类物质尤其是几种极毒性化合物如多氯代二苯二(?)(?)(PCDDs)和多氯代二苯呋喃(PCDFs)等化合物的检测技术成果。 相似文献