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1.
The present study constitutes the first investigation to demonstrate pyrethroid bioaccumulation in marine mammals, despite the assumption that these insecticides are converted to non-toxic metabolites by hydrolysis in mammals. Twelve pyrethroids were determined in liver samples from 23 male franciscana dolphins from Brazil. The median concentration values for total pyrethroids were 7.04 and 68.4 ng/g lw in adults and calves, respectively. Permethrin was the predominant compound, contributing for 55% of the total pyrethroids. Results showed a distinct metabolic balance of pyrethroids through dolphin life. High loads are received at the beginning of their lives and, when they reach sexual maturity, these mammals seem to degrade/metabolize pyrethroids. Maternal transfer of these compounds was also evaluated through the analysis of breast milk and placenta samples. Pyrethroids were detected in both matrices, with values between 2.53–4.77 ng/g lw and 331–1812 ng/g lw, respectively. Therefore, for the first time, a study shows mother-to-calf transfer of pyrethroids by both gestational and lactation pathways in dolphins.  相似文献   

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3.
Illicit trafficking of fissionable material in container cargoes is recognized as a potential weakness in Nuclear Security. Triggered by the attacks of 11 September 2001, measures were undertaken to enhance maritime security in extension to the Safety Of Life At Sea Convention and in line with the US Container Security Initiatives. Effective detection techniques are needed that allow the inspector to intercept illicit trafficking of nuclear weapons components or components of other nuclear explosive devices. Many security measures focus on active interrogation of the container content by X-ray scan, which might be extended with the newly developed tagged neutron inspection system. Both active interrogation techniques can, with the current huge volume of container traffic, only be applied to a limited number of selected containers. The question arises whether a passive detection technique can offer an alternative solution. This study investigates if containers equipped with a small passive detector will register during transport the neutron irradiation by fissionable material such as plutonium in a measurable way. In practice, 4/5 of the containers are about 1/8 filled with hydrogenous material and undergo a typical 2 months route. For this reference case, it was found that the most compatible passive detector would be an activation foil of iridium. Monte-Carlo simulations showed that for the reference case the activity of a 250 μm thin foil with 6 cm2 cross-section would register 1.2 Bq when it is irradiated by a significant quantity of Reactor-Grade PuO2. However this activity drops with almost two orders of magnitude for other fillings and other isotopic compositions and forms of the Pu-source. The procedure of selecting the target material for Pu detection is detailed with the theoretical methods, in order to be useful for other applications. Moreover the value of such additional passive sensors for securing maritime container transport is situated within the global framework of the First, Second and Third Line of Defense against illicit trafficking.  相似文献   

4.
Environment, Development and Sustainability - The issues concerning mining have been causing a wide variety of emotions. Objection to and disagreement with new investments, but also social...  相似文献   

5.
Australian resource-extraction industries—mining, fisheries and forestry—operate year-round in the natural environment with all three exposed to climate extremes and to long-term climatic change. However, the industries differ in terms of size, ownership and mobility. Although mining companies are ‘mobile,’ a commitment to a mine site makes them immobile at a location dictated by the presence of a mineral; forestry of natural and managed trees takes place in a specifically selected location that can be changed given a reasonably long time-frame and high financial investment; fishing is the last of the major hunting industries, and despite operating from fixed ports, fishers chase fish across the ocean. All three industries as employers and product providers seek a sustainable future under a changing climate but are subject to environmental variability that impacts on their activities. As each industry has historically dealt with and survived major climate impacts, they typically consider themselves to be resilient, although we illustrate in several case studies that recent climate variability significantly impacts productivity and current resilience is limited. Projected climate change and variability are likely to exacerbate impacts on these industries through new or intensified hazards. Although each industry performs risk management controls to minimize climate-related impacts, a new approach incorporating future climate projections in addition to historical experiences would better prepare each to reduce vulnerability to changing climate. We find that wholesale transformation may not be appropriate or necessary at this time for these industries, and in most cases anticipatory, incremental adaptation should be encouraged, while larger-scale changes are considered in the longer term. Additionally, to overcome some of the barriers and promote the drivers of adaptation, we suggest that a model of adaptive governance coupled with greater use of climate champions may be the most effective method for improving adaptation uptake in these industries.  相似文献   

6.
Efficient use of energy helps to achieve increased production and productivity and contributes to the economy, profitability, and competitiveness of agricultural sustainability of rural communities. Evaluation of wheat and barley production systems in view of energy balance was conducted in Khorasan Razavi Province, Iran. Data were collected by using a face-to-face questionnaire from wheat and barley fields in 2011. Results revealed that total energy input for wheat was 51,040 MJ ha?1 and for barley 44,866; in wheat and barley systems, renewable energy was consumed by 25.43 and 23.53 %, while non-renewable energy was consumed by 74.57 and 76.47 %, respectively. Energy use efficiency, energy productivity, and net energy were 1.7 kg MJ?1, 0.088 kg MJ?1, and 35,987 MJ ha?1 in wheat system and 1.83 kg MJ?1, 0.092 kg MJ?1, and 33,833 MJ ha?1 in barley system, respectively. Energy intensiveness in wheat fields (61.84 MJ $?1) was higher than in barley fields (58.71 MJ $?1). Also, benefit-to-cost ratio in wheat system (1.59) was higher than in barley system (1.35). In general, production in barley fields was more sustainable than wheat production because, in view of ecological indices such as amount of energy use and renewable energy consumption, it was more environment-friendly production.  相似文献   

7.
Mercury (Hg) is a global contaminant impacting even remote environments. In alpine watersheds, glacial meltwater is a source of Hg, which accumulated in glaciers during the 1960–1980 cooling cycle. The considerable variation observed for Hg exposure of alpine animals in proximal watersheds could result from differences among those watersheds in Hg loading from glacial meltwater. Alternatively, variation may be the result of hydrology, atmospheric Hg deposition patterns, or food web characteristics. To examine those possibilities, we measured Hg in ospreys (Pandion haliaetus), apex predators in 15 watersheds in western Canada. Mercury levels in feathers of nestlings increased with increasing modeled atmospheric deposition rates and decreased with lake size. In eggs mercury decreased with δ13C, an indicator of food web structure, and with pH and elevation. Thus, Hg levels in chicks were strongly associated with local patterns relevant when the chicks were growing (e.g. the period post-snow melt: Hg deposition, lake size) while Hg levels in eggs were weakly associated with local patterns relevant during the snow melt (elevation, δ13C), with the remainder of the Hg variation in eggs determined by other factors such as possible Hg accumulation by the adult elsewhere. Modeled atmospheric deposition from prevailing upwind locations including Asia, followed by runoff into small lakes, were related to Hg patterns in osprey, with little apparent role for recent melting of glaciers. Our study highlights the importance of physical patterns to the environmental chemistry of top predators.  相似文献   

8.
The nonionic biodegradation-resistant ("hard") alkylphenol ethoxylate (APEO) surfactants and their degradation products are known endocrine disrupting chemicals (EDCs). We report here the findings concerning the APEOs concentrations and homologic distribution profiles in Israel's estuarine and coastal zone seawater to serve as a case study. The concentrations in sewage-containing rivers, estuaries and 50-60-m offshore sea (Mediterranean) water were found to be 12.5-75.1, 4.2-25.0 and 0.9-2.6 microg/L, respectively. The corresponding homologic distribution profiles were found to be within the range of 1-10% each, somewhat skewing, as expected, towards the more toxic shorter-chain ethoxylates. Egg production by zebrafish, exposed to 75, 25 and 10 microg/L of a typical industrial APEOs was reduced up to 89.6%, 84.7% and 76.9%, respectively, between the 8th and 28th days of exposure. Apparently, there is a potential APEOs-related ecotoxicological health risk problem.  相似文献   

9.
It has been nearly 20 years since a working definition for “sustainable development” was put forward by the World Commission on Environment and Development. The concept endures in the mission statements and frameworks of action of various societal actors, including those of neighborhood associations, metropolitan development authorities, environmental ministries, and United Nations (UN) specialized organizations, to name a few. Yet many observers doubt that sustainable development is occurring in poor countries. This failure, the critics contend, stems from miserly transfers of foreign aid. The extent to which inadequate aid is to blame for poor environmental/developmental outcomes is an open question. But vocal demands for increasing aid to meet sustainable development goals come from many parts of society and are persistent. Exhortations for more aid to help poor countries are noble, perhaps even justifiable, but there are understandable doubts about the wisdom of transferring large capital and technical resources to countries that are slow to adopt needed institutional reforms. Aid without institutional reform is a recipe for wasted resources and donor fatigue. Worse, it may enhance inequities of wealth and power in recipient countries. There are few illustrations to draw on demonstrating how institutionally impoverished societies are affected when they are compelled to absorb massive aid inputs over a short period––a remedy suggested by some prominent aid experts. As a proxy, it is valuable to examine instances where swift macroeconomic changes, spurred by external investment and export-led growth, has occurred without significant institutional development. The case of Equatorial Guinea and its sudden oil riches is examined to discern whether, in the absence of meaningful institutional reform, rapid and profound increases in foreign direct investment and export income enable poverty alleviation and sustainable development.
Matthew R. AuerEmail:
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10.
The world coastal-zone population and coastal tourism are expected to grow during this century. Associated with that, there will be an increase in the use of sunscreens and cosmetics with UV-filters in their formulation, which will make coastal regions worldwide susceptible to the impact of these cosmetics. Recent investigations indicate that organic and inorganic UV-filters, as well as many other components that are constituents of the sunscreens, reach the marine environment - directly as a consequence of water recreational activities and/or indirectly from wastewater treatment plants (WWTP) effluents. Toxicity of organic and inorganic UV filters has been demonstrated in aquatic organism. UV-filters inhibit growth in marine phytoplankton and tend to bioaccumulate in the food webs. These findings together with coastal tourism data records highlight the potential risk that the increasing use of these cosmetics would have in coastal marine areas. Nevertheless, future investigations into distribution, residence time, aging, partitioning and speciation of their main components and by-products in the water column, persistence, accumulation and toxicity in the trophic chain, are needed to understand the magnitude and real impact of these emerging pollutants in the marine system.  相似文献   

11.
Regional Environmental Change - Lake Baikal is the largest near-surface global freshwater source and of high interest for water quality alterations, as deterioration of water quality is a main...  相似文献   

12.
Regional Environmental Change - Climate change is projected to prolong Finland’s short growing season at both ends though warming autumns are not expected to benefit arable crops such as...  相似文献   

13.
Russian Journal of Ecology - The question of the nature (random or ordered) of the loss of species in plant communities as a result of an increase in the participation of dominants is considered....  相似文献   

14.
BackgroundExposure to disinfection by-products (DBPs) during pregnancy was associated with reduced foetal growth. Genetic susceptibility might play a role, especially for genes encoding for the Cytochrome P450 (CYP2E1) and Glutathione S-Transferase (GST) enzymes, involved in metabolism and activation of DBPs. Few epidemiological studies evaluated these gene-environment interactions and their results were never replicated.ObjectiveThis study aims to examine interactions between trihalomethanes (THM) or haloacetic acids (HAA) exposure and genetic polymorphisms on small for gestational age (SGA) neonates by investigating single nucleotide polymorphisms (SNPs) in CYP2E1 gene and GSTM1 and GSTT1 deletions in mothers-children pairs.MethodsA population-based case-control study of 1549 mothers and 1455 children was conducted on SGA and THM/HAA exposure. DNA was extracted from blood or saliva cells. Targeted SNPs and deletions were genotyped. Statistical interaction between SNPs/deletions and THMs or HAAs in utero exposure with regard to SGA occurrence was evaluated by unconditional logistic regression with control of potential confounders.ResultsPreviously reported positive modification of the effect of THM uterine exposure by mothers or newborns CYP2E1 rs3813867 C allele or GSTM1 deletion was not replicated. However interactions with CYP2E1 rs117618383 and rs2515641 were observed but were not statistically significant after correction for multiple testing.ConclusionsPrevious positive interactions between THMs exposure and CYP2E1 and GSTM1 were not replicated but interactions with other CYP2E1 polymorphisms are reported.  相似文献   

15.
It is shown here that one burns 1 gallon of gasoline equivalent in fossil fuels to produce 1 gallon of gasoline equivalent as ethanol from corn. When this corn ethanol is burned as a gasoline additive or fuel, its use amounts to burning the same amount of fuel twice to drive a car once. Therefore, the fuel efficiency of those cars that burn corn ethanol is halved. The widespread use of corn ethanol will cause manifold damage to air, surface water, soil and aquifers. The overall energy balance of corn conversion to ethanol demonstrates that 65% of the input energy is lost during the conversion. Carbon dioxide sequestration by corn is nullified when corn ethanol is burned, and there will be additional carbon dioxide, nitrous oxides, and sulfur oxide emissions from the fossil fuels used to produce the ethanol. Students in the Spring 2003 CE24 Freshman Seminar offered at U.C. Berkeley by the Civil and Environmental Engineering Department Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

16.
It has been widely acknowledged that people’s beliefs and perceptions influence implementation of climate change adaptation. Regarding perception barriers, some authors keep highlighting the confused definition of adaptation and its various interpretations. Our research contributes to this area by exploring how adaptation to climate change is perceived through 83 semi-structured interviews with stakeholders (public and municipal organizations, ENGO, private sector) from Montreal and Paris. Our results demonstrate a mirror opposition in the perception of adaptation to climate change. Indeed, while several respondents interpreted adaptation as a resignation, many interviewees perceived adaptation as an opportunity. The analysis showed that adaptation referring to resignation includes the ideas of a non-action and detrimental to mitigation; an excuse for not changing; anxiety about climate change; fatalism; and human failure. Adaptation perceived as an opportunity is divided into a source of creativity; toward sustainable development; led by the emergency; and awareness and making society of its responsibilities. Our findings confirm that terminological ambiguity of the term “adaptation” has to be considered in the decision-making process, which can be influenced by the perception of stakeholders.  相似文献   

17.
This paper examines ideologies about nature and the environment in popular, animated Hollywood films—including The Lorax, Wall-E, and Ice Age 2—through a symptomatic reading. The primary goal of the analysis is to elucidate key omissions in these texts through an assessment of the problematic—defined in this research as an a-priori answer to perceived audience concerns regarding the role of consumerism and corporate culture in environmental problems. Silences in the films revolve around: how environmental problems are defined; what the consequences are; who the responsible parties are; and what potential solutions exist to mitigate them. The significance of the research is underscored by the formation of an increasingly intimate relationship between children, consumer culture, and commercial media in the USA, as well as the increasingly dire information emerging about global environmental issues. This analysis reveals the dual, often conflicting, messages that commercial film provides for its young audiences about pivotal environmental problems and their potential resolution.  相似文献   

18.
We present a new multimedia chemical fate model (SESAMe) which was developed to assess chemical fate and behaviour across China. We apply the model to quantify the influence of environmental parameters on chemical overall persistence (POV) and long-range transport potential (LRTP) in China, which has extreme diversity in environmental conditions. Sobol sensitivity analysis was used to identify the relative importance of input parameters. Physicochemical properties were identified as more influential than environmental parameters on model output. Interactive effects of environmental parameters on POV and LRTP occur mainly in combination with chemical properties. Hypothetical chemicals and emission data were used to model POV and LRTP for neutral and acidic chemicals with different KOW/DOW, vapour pressure and pKa under different precipitation, wind speed, temperature and soil organic carbon contents (fOC). Generally for POV, precipitation was more influential than the other environmental parameters, whilst temperature and wind speed did not contribute significantly to POV variation; for LRTP, wind speed was more influential than the other environmental parameters, whilst the effects of other environmental parameters relied on specific chemical properties. fOC had a slight effect on POV and LRTP, and higher fOC always increased POV and decreased LRTP. Example case studies were performed on real test chemicals using SESAMe to explore the spatial variability of model output and how environmental properties affect POV and LRTP. Dibenzofuran released to multiple media had higher POV in northwest of Xinjiang, part of Gansu, northeast of Inner Mongolia, Heilongjiang and Jilin. Benzo[a]pyrene released to the air had higher LRTP in south Xinjiang and west Inner Mongolia, whilst acenaphthene had higher LRTP in Tibet and west Inner Mongolia. TCS released into water had higher LRTP in Yellow River and Yangtze River catchments. The initial case studies demonstrated that SESAMe performed well on comparing POV and LRTP of chemicals in different regions across China in order to potentially identify the most sensitive regions. This model should not only be used to estimate POV and LRTP for screening and risk assessments of chemicals, but could potentially be used to help design chemical monitoring programmes across China in the future.  相似文献   

19.
The (usually not professed) truth is that we are not destroying the planet due to lack of technology, but due to lack of application of technology. Indeed, opportunities exist for renewable energy technologies’ diffusion under the new climate change regime as they contribute to global sustainability through GHG mitigation and, they conform to national priorities by leading to the enhancement of local economic activity, capacities and infrastructure. The clean development mechanism (CDM), although is considered one of the global policy tools to contribute to sustainable development and technology transfer, has recently been criticised for its unequal distribution of projects across countries and for insufficiently being embedded in developing countries’ national energy context. In the above framework, this article presents the ENTTRANS approach, five indicative renewable energy technologies, and insights about a more effective application of CDM, which may be part of the international process striving towards sustainable development.  相似文献   

20.
Eco-certification has been used as a tool to mitigate adverse effects of aquaculture production and might thus be understood as a private approach to sustainable ecosystem management. In production forests in Ca Mau, Vietnam, where mangrove have suffered degradation despite legal protection, different projects have targeted reversing this trend by means of private certification using the ‘Naturland’ organic standard as a reference. So far the outcomes have, however, been proven unsatisfactory. With the aim to better understand the reasons for these poor outcomes, a survey of forty households was conducted in a production forest in Rach Goc commune, Ngoc Hien District. We evaluated farmers’ perceptions on mangrove management, the drivers guiding shrimp farming, and whether there was a difference between participants and non-participants in a former ‘Naturland’ organic project. To complement the survey, a range of stakeholders involved in shrimp value chains were interviewed to better understand the terms and benefits of certification. The results of this survey suggested that, when applied to shrimp–mangrove farming systems in production forests in Ca Mau, ‘eco-certification’ and associated benefits are not very satisfactory. The survey results revealed that certified farms do not show significant differences to non-certified farms in terms of social and environmental benefits. As far as the implementation process was concerned, the survey results showed that a failure to integrate local farmers as participants consequently resulted in households becoming ‘objects’ for certification and not project partners with equal weight and power. It appears that rather than being a tool for improvement, ‘Naturland’ certification for shrimp–mangrove farming systems in Ca Mau’s production forests has become an end in itself.  相似文献   

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