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1.
Upcoming decades will experience increasing atmospheric CO2 and likely enhanced O3 exposure which represents a risk for the carbon sink strength of forests, so that the need for cause-effect related O3 risk assessment increases. Although assessment will gain in reliability on an O3 uptake basis, risk is co-determined by the effective dose, i.e. the plant's sensitivity per O3 uptake. Recent progress in research on the molecular and metabolic control of the effective O3 dose is reported along with advances in empirically assessing O3 uptake at the whole-tree and stand level. Knowledge on both O3 uptake and effective dose (measures of stress avoidance and tolerance, respectively) needs to be understood mechanistically and linked as a pre-requisite before practical use of process-based O3 risk assessment can be implemented. To this end, perspectives are derived for validating and promoting new O3 flux-based modelling tools.  相似文献   

2.
Steps towards a European dioxin emission inventory   总被引:7,自引:0,他引:7  
Quass U  Fermann MW  Bröker G 《Chemosphere》2000,40(9-11):1125-1129
The results of a project aiming at collection and evaluation of information regarding the industrial and non-industrial emission sources for dioxins and furans (PCDD/PCDF) in 17 European Countries (EU 15, CH, N) are presented. An overview about national documents covering dioxin emission inventories for the period 1990-1995 is given. Some data on emissions associated with residual materials, waste and waste water are presented additionally. Based on the air emission data contained in these documents the most important emission sources were determined which are assumed to cover about 90% of the overall emissions. For the selected sources and for all 17 countries new estimates of the atmospheric PCDD/PCDF emissions were derived from average emission factors and statistical activity rates for the year 1994. As a result, on the European scale the largest annual PCDD/PCDF emission is assessed to be released from municipal waste incineration, quite closely followed by emissions from iron ore sintering. Considerable releases of dioxins and furans--based, however, on highly uncertain data--are further assessed for domestic burning, accidental fires and (former) use of contaminated wood preservatives (pentachlorophenol). A lower but still significant emission is further assigned to the sector of non-ferrous metal production; particular processes used in this branch proved to generate very high PCDD/PCDF flue gas concentrations.  相似文献   

3.
4.
Energy return on investment: toward a consistent framework   总被引:2,自引:0,他引:2  
Mulder K  Hagens NJ 《Ambio》2008,37(2):74-79
Numerous technologies have been proposed as partial solutions to our declining fossil energy stocks. There is a significant need for consistent metrics to compare the desirability of different technologies. The ratio of energy produced to energy consumed by an energy production technology-known as the energy return on investment (EROI)-is an important first indicator of the potential benefits to society. However, EROI analysis lacks a consistent framework and has therefore yielded apparently conflicting results. In this article, we establish a theoretical framework for EROI analysis that encompasses the various methodologies extant in the literature. We establish variations of EROI analysis in two different dimensions based on the costs they include and their handling of nonenergy resources. We close by showing the implications of the different measures of EROI upon estimating the desirability of a technology as well as for estimating its ultimate net energy capacity.  相似文献   

5.
BACKGROUND, AIM AND SCOPE: The Damage-Function method is an efficient tool recently used in decision-making processes concerning environmental management. It is based on finding the relation between the origin of an environmental charge, and its impact on human health and the environment. The aim of the present investigation was to assess the positive impacts, also called benefits, of changes in environmental quality, and the economic viability of an industrial project on reduction of PCDD/F emissions. It has been developed with monetary criteria of two worldwide ambits: USA and European-Union countries. METHODS: The current study is a continuation of a previous investigation in which Substance Flow Analysis and Control Analysis Techniques were used to identify and to analyze all main flow values of PCDD/Fs inside the system of Tarragona Province (Spain). In the present study, Cost-Benefit Analysis (CBA) has been employed. The benefits derived from a minimization in the incidence of cancer due to a reduction in the emission of PCDD/Fs have been evaluated considering the value of a statistically saved life (VSL). Statistical analysis about uncertainty has also been incorporated. Here, the Monte Carlo simulation technique has been used. RESULTS: It is shown that CBS results depend firstly on the kind of VSL used. In fact, the differences between the decisions as a result of applying monetary criteria in USA and EU can be explained by differences between VSL values. CONCLUSION AND RECOMMENDATION: It is concluded that, for prices estimated in Euros, the emission cleaning project in the industrial plant is not feasible under any circumstance. However, although CBA seems to be a good analytical method, the final decision corresponds to the managers, who must weigh up not only the monetary criteria, but factors such as social questions.  相似文献   

6.
Present governmental and environmental policy is curative and reactive in nature, directed towards cleaning up past environmental disasters and passing laws to limit pollutants emitted by individuals and enterprises. Such policies fail to recognize that the root causes of environmental degradation are the result of an exponentially expanding population and a rising standard of living. No environmental programme can be successful without controlling population and reforming governmental policies in the areas of family planning, abortion, immigration, and economic regulation. Controlling population by liberalizing family planning and abortion laws is a more humane approach than reducing standards of living, especially in developing countries, where poverty is the cause of so much misery.  相似文献   

7.
Environmental Science and Pollution Research - Improper disposal of animal waste is responsible for several environmental problems, causing eutrophication of lakes and rivers, nutrient overload in...  相似文献   

8.
Environmental Science and Pollution Research - The study determines the development of the sustainability reporting domain using a dataset of publications extracted from the Web of Science (WoS)...  相似文献   

9.
A case study is presented where an integrated, ecologically relevant exposure assessment is presented for a polluted lowland river. Using partial least squares regression of latent structures (PLS), an analysis of the impact of two effluents on physico-chemical water quality measures, macroinvertebrate and diatom communities, and in situ bioassay responses with four different test species are combined into an integrative exposure assessment. Bioassays focussed on growth and condition related endpoints, because they are key functional processes of organisms and populations. Integrating these multiple lines of evidence, we were able to discriminate among the impact of both effluents, link changes in physico-chemical water quality with bioassay endpoints and ecological quality of the ecosystem, and address the importance of integrating all information into one exposure assessment framework. The bioassays under field conditions indicated that most endpoints measured are a reflection of ecological effects rather than pollution related effects, or at least a combination of both ecological and toxicological effects. Factors such as food availability clearly influenced the outcome of in situ bioassays and ecological information was essential to explain observed discrepancies when trying to extrapolate bioassay results from the laboratory to the field.  相似文献   

10.
Zheng MH  Bao ZC  Zhang B  Xu XB 《Chemosphere》2001,44(6):1335-1337
An extensive investigation on the input, formation and fate of PCDD/Fs in a pulp mill using reeds as raw materials in China was carried out. The main PCDD/Fs input in the production process came from reeds, which may be contaminated by PCDD/Fs from sodium pentachlorophenate to control snailborne schistosomiasis. High levels of I-TEQ in the products were observed.  相似文献   

11.
Emerging after World War II “the environment” as a modern concept turned in the years around 1970 into a phase of institutionalization in science, civic society, and politics. Part of this was the foundation of journals. The majority became “environmental specialist journals”, typically based in established disciplines. Some became “environmental generalist journals”, covering broad knowledge areas and often with an ambition to be policy relevant. A significant and early member of the latter category was Ambio, founded 1972. This article presents an overview of the journal’s first 50 years, with a focus on main changes in scientific content, political context, and editorial directions. A key finding is that the journal reflects an increasing pluralization of “the environment” with concepts such as global change, climate change, Earth system science, Anthropocene, resilience, and environmental governance. Another finding is that the journal has also itself influenced developments through publishing work on new concepts and ideas.  相似文献   

12.

Owing to their ultrathin two-dimensional structure and efficient catalytic ability for persulfate activation, graphene-based nanocarbons exhibit considerable application potential in fabricating carbonaceous composite membranes for in situ catalytic oxidation to remove organic pollutants. This approach offers significant advantages over conventional batch systems. However, the relationships between the physicochemical properties of carbon mats and performance of graphene-based catalytic membranes in water purification remain ambiguous. Herein, we summarize the main mechanisms of in situ catalytic oxidation and the facile fabrication strategies of carbonaceous composite membranes. Different factors influencing the performance of graphene-based catalytic membranes are comprehensively discussed. The defective level, heteroatom doping, and stacking morphology of carbon mats and operational conditions during filtration play critical roles in the oxidative degradation of target pollutants. Long-term operation leads to the deterioration of catalytic activity and transmembrane pressure, especially in the complex water matrix. Finally, the present challenges and future perspectives are presented to improve the anti-fouling performance and catalytic stability of membranes and develop scalable fabrication methods to promote the engineering applications of in situ catalytic oxidation in real water purification.

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13.
The chemical product diaryl-p-phenylene diamine (DAPD), produced by The Goodyear Tire & Rubber Company as POLYSTAY 100® (CAS 68953-84-4), is employed as an antidegradant in polymers used in tires and industrial rubber products. Previous evaluations pertaining to the ecological fate of DAPD indicated a lack of biodegradative activity in aquatic media. In order to further pursue the biodegradation potential of DAPD, it was deemed necessary to enhance the sensitivity of the aquatic biodegradation assay through (a) employment of a radiotracer of the test substance, and (b) optimisation of conditions for achieving maximal solubilisation of test material in the aquatic media of the incubation vessels. Test vessels were prepared according to the OECD ready biodegradability test guidelines, with DAPD added on silica gel at concentrations of 10 or 100 μg L−1, together with a surfactant to aid solubilisation. After 63 d incubation up to 37% mineralisation was measured and up to 29% of the applied radioactivity was incorporated into cell biomass. Also, after 28 d no DAPD could be measured in solution by radio-TLC and HPLC–MS. These three results demonstrate that the antioxidant DAPD undergoes microbiologically mediated biodegradation and is highly unlikely to persist in the environment.  相似文献   

14.
This study correlated extractabilities of 37 d aged phenanthrene residues in four dissimilar soils with the fraction that was available for earthworm (Lumbricus rubellus) accumulation and microorganism (Pseudomonas sp.) mineralisation. Extractability was determined using two established techniques, namely, (1) a water based extraction using CO(2) equilibrated water and (2) an aqueous based hydroxypropyl-beta-cyclodextrin (HPCD) extraction. Results showed no relationship between earthworm accumulation and phenanthrene extractability using either HPCD (r(2)=0.07; slope=-4.76; n=5) or the water based extraction (r(2)=0.31; slope=-5.34; n=5). Earthworm accumulation was overestimated by both techniques. In contrast, the fraction of phenanthrene extractable using both the HPCD technique and the water based extraction correlated strongly with microbial mineralisation. However, the slopes of these linear relationships were 0.48 (r(2)=0.96; n=10), and 0.99 (r(2)=0.88; n=10) for the water based extraction and HPCD, respectively. Thus, the HPCD extraction provided values that were numerically close to the mineralisation values, whilst the water based extraction values were approximately half the mineralisation values. It is submitted that HPCD extraction provided an appropriate method of assessing the fraction of contaminant available for microbial mineralisation in these dissimilar soils.  相似文献   

15.
采用水热法制备新型光-类芬顿纳米钒酸铁,通过X射线衍射(XRD)、粒径和比表面积(BET)对产物进行表征。以盐酸四环素模拟废水,通过光-类芬顿体系下对盐酸四环素的催化降解效果评价钒酸铁的催化活性,研究分析光源、盐酸四环素初始浓度、pH值、FeVO4的用量以及H2O2的用量对盐酸四环素催化降解性能的影响。结果表明,在可见光下,盐酸四环素初始浓度为50 mg·L-1,pH值为7,H2O2的用量为60 μL时,1.5 g·L-1纳米钒酸铁,经过120 min反应后降解率为97.63%。  相似文献   

16.
As is the case in most developing countries, China relies on command-and-control regulation to control air pollution. While it has instituted a modest air pollution levy system in the past 20 years for emissions in excess of standards, the effect on emission levels has been minimal. This paper focuses on how to use emissions trading as a policy instrument to achieve cost-effective reductions in air pollution in Beijing. Emissions or allowance trading has been widely applied to air pollution control in the USA during the past 25 years. Three of the most recent programmes will be examined, which provide applicable experience for possible SO2 and NOx trading in the Beijing region. A trading strategy for Beijing will be proposed by comparing the economic and political institutional differences between the USA and China, which could eventually facilitate acceptance of an international greenhouse gas trading system.  相似文献   

17.
Environmental Science and Pollution Research - Aerogels are a unique class of nanoporous ultralight materials exhibiting wide range of textural characteristic properties and tunable porosities. Due...  相似文献   

18.
Nonylphenols (NPs) are the primary stable metabolites of alkylphenol polyethoxylates (APEs), a family of compounds widely used in industry and in some domestic products. As NPs accumulate in sediments in aquatic environments, the risk to benthic organisms needs to be assessed. In this study 4NP-spiked sediments were tested on larvae of the dipteran Chironomus riparius. First instar larvae obtained from populations at three different sources were used. To spike the sediments, an equilibration procedure between water and sediment was adopted to avoid the use of solvents. Lower 10-d LC50 values were determined for two populations of C. riparius from clean environments (315-465 and 315-350 microg g(-1) d.w., respectively) than those of a strain deriving from a population collected in a polluted river (600-680 microg g(-1) d.w.). Larval growth always decreased with increasing 4NP concentration but without any defined trend. The results of this study suggest that tolerance to the toxicant can be developed in populations of polluted environments and that testing procedures should be standardised.  相似文献   

19.
20.
This study characterizes the cholinesterasic forms present in the bivalve Corbicula fluminea, through the analysis of differential affinity towards various substrates and inhibitors. This approach also permitted the validation of cholinesterase inhibition in the mentioned species for monitoring purposes by evaluating the inhibitory activity of a detergent (SDS) and a pesticide (chlorfenvinphos), both in vitro and in vivo. The cholinesterasic form present in the tissues of C. fluminea showed intermediate properties in terms of its relation with substrates and inhibitors. Furthermore, it was not inhibited by the detergent SDS under any of the test conditions, but was clearly inhibited by the selected organophosphate. The data show clearly that the main cholinesterasic form in C. fluminea is responsive to the organophosphate chlorfenvinphos, thus supporting the use of this biomarker for the environmental monitoring of specific contaminants such as anticholinesterasic pesticides. Despite not being commonly attained in the wild, the levels of chlorfenvinphos required to elicit a significant ChE inhibition were only one order of magnitude above actual values of aquatic contamination by this pesticide.  相似文献   

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