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1.
Contaminant input into the environment can affect the biochemical responses of exposed organisms. Activity of conjugation enzymes, such as glutathione S-transferase (GST) has been proposed as a biomarker of susceptibility to the presence of potentially damaging xenobiotics. The aim of the present study was to evaluate the activity of total and Pi-class GST in the hepatopancreas of pink-shrimp Farfantepenaeus brasiliensis. The shrimp were caught at a single site at Concei??o Lagoon and transplanted to another site (Canto da Lagoa - CA) in the same lagoon, and to the laboratory (LAB), where they were kept for 15 days. This experiment was carried out in winter 2003 and in summer 2004. Shrimp were sampled before the exposure, at a zero time (t0), and after 15-days at CA site and LAB. The activity of total GST and Pi-isoform were analyzed using CDNB and ethacrynic acid (EA) as substrates, respectively. Shrimp caught in winter showed higher levels of Pi-class GST than those caught in summer, for both t0 and CA groups. Moreover, differences in the activity of this GST isoform between groups were observed only in winter, where the animals from t0 and CA groups presented higher activity when compared to those kept in the laboratory. This difference could be associated either to changes in the contaminant input or to other water quality parameters in this ecosystem. The elevated GST Pi activity observed in the shrimp of both t0 and CA groups sampled in winter could be related to salinity, since it was higher in winter than in summer. We could also suggest a possible association of this finding to a seasonal metabolic variation in this penaeid. If that is the case, one should take into account these alterations when considering the use of this GST isoform as biomarker in F. brasiliensis in environmental monitoring programs.  相似文献   

2.
The current status of ecotourism in rural China was analyzed in this paper.Empirical surveys covering the whole country indicate that ecotourism in rural China has attracted a large number of tourists who,however,didn’t generate revenues that can match the number.Although the environmental quality of those rural ecotourism destinations is high with little negative impacts,several problems have already appeared,suggesting a need to monitor those areas.The current practice of interpretation in most rural ecotourism destinations did not provide environmental education opportunities to the tourists.And local communities need more effective ways to decide on the prospects of local ecotourism development by themselves.Finally,a few recommendations for improving the sustainability of ecotourism destinations were provided.  相似文献   

3.
以长江中游城市群60处国家水利风景区为研究对象,利用最邻近点指数、Voronoi多边形面积变异系数、核密度分析、图层叠加分析等空间分析手段和GIS空间分析工具,对区域水利旅游资源的空间结构特征进行分析。解释了水利风景区空间分布的影响因素。最后基于谷歌地图搜索测算了各水利风景区对于相应城市群地级市的交通可达性。结果表明:水利风景区呈随机、均匀分布态势,但有集聚分布倾向;空间集聚形态上表现为三处高密度集聚圈、三处低密度集聚圈、一处真空地带;水利风景区空间分布受资源禀赋、交通区位、政策支撑等多因素影响;水利风景区的通达度均值为212.15分钟,大部分水利风景区可达性并不理想;湖南各地级市到达所有水利风景区平均耗时优于江西和湖北。  相似文献   

4.
Earth System Analysis was postulated as a theory by Hans-Joachim Schellnhuber in 1998 as a way to characterise the Earth System—the coupled relationship between the environment and humans. Within this theory is the notion of Geocybernetics—management of the Earth System in order to achieve strategies and mechanisms of co-evolution between the environment and humans. This is regarded as the concept and application of sustainable development. However, whilst fundamental definitions in Earth System Analysis are presented for the coupled relationship between the environment and humans, no such definitions exist for sustainable development within the Earth System context. Consequently, this paper presents a mathematical model of sustainable development that provides for the fundamental abstraction of the key concepts and parameters necessary for sustainable development to occur. The model utilises basic mathematics to detail these concepts and parameters, as well as the conditions required for sustainable development to occur. The model presented is, in some regards, a work in progress, and further refinements will be made given the nature of the research performed to this point, i.e. the fundamental mathematical definition of sustainable development and its application. However, the research conducted thus far has made it reasonable to communicate the findings made up to the present point. The paper also provides a brief example of the application of the model to an environmental impact assessment of a metro rail scheme in India, for the purpose of evaluating the level of sustainable development (if appropriate) for the project under consideration.  相似文献   

5.
For centuries, mankind has contributed to irreversible environmental changes, but due to the modern science of recent decades, scientists are able to assess the scale of this impact. The introduction of laws and standards to ensure environmental cleanliness requires comprehensive environmental monitoring, which should also meet the requirements of Green Chemistry. The broad spectrum of Green Chemistry principle applications should also include all of the techniques and methods of pollutant analysis and environmental monitoring. The classical methods of chemical analyses do not always match the twelve principles of Green Chemistry, and they are often expensive and employ toxic and environmentally unfriendly solvents in large quantities. These solvents can generate hazardous and toxic waste while consuming large volumes of resources. Therefore, there is a need to develop reliable techniques that would not only meet the requirements of Green Analytical Chemistry, but they could also complement and sometimes provide an alternative to conventional classical analytical methods. These alternatives may be found in bioassays. Commercially available certified bioassays often come in the form of ready-to-use toxkits, and they are easy to use and relatively inexpensive in comparison with certain conventional analytical methods. The aim of this study is to provide evidence that bioassays can be a complementary alternative to classical methods of analysis and can fulfil Green Analytical Chemistry criteria. The test organisms discussed in this work include single-celled organisms, such as cell lines, fungi (yeast), and bacteria, and multicellular organisms, such as invertebrate and vertebrate animals and plants.  相似文献   

6.
Coping with global environmental change demands new forms of civic engagement and interaction able to transform passive audiences attending to the drama of unsustainability into committed actors for sustainability. This entails linking diverse sources of scientific knowledge with personal experiences, emotion and ethical judgments. In this paper, we assess the potential as well as the limitations of innovative theatre-based participatory tools and methods aimed at supporting sustainability learning and agent transformation. To this aim, we first review a series of experiences using theatrical performance and introduce the notion of performative methods. Second, we assess to what extent these new approaches can be of relevance in environmental action research and sustainability science, practice and learning. Finally, we list a series of key research questions to further guide methodological innovation in this promising area of sustainability science and practice. Our findings show a growing and successful use of such methodologies worldwide, both in academia and in implementation-oriented approaches. An increasing number of topics and complexity is being embraced by these methods, offering a fertile ground for innovation in participatory sustainability science.  相似文献   

7.
A sustainable national policy on waste electronic and electrical equipment reuse has to ensure an integrated environmental economic and social approach. In this paper, a quantitative model is developed that permits a comparative analysis of re-use and non-re-use scenarios from an environmental and economic perspective. The model demonstrates the importance of considering user consumption profiles and the changing national electricity generation portfolio in determining the best end-of-life strategy, whether it should be reuse or recycling. A case study of Ireland is used to demonstrate the model. From a social perspective, qualitative aspects of reuse, such as the job creation potential and the impact on prosperity for low income families, are also considered. Reuse of white goods, if conducted through social enterprises, will create more employment than an equivalent amount of recycling for those most vulnerable to unemployment. Any environmental and social dividends from re-use can be realized only in the context of an economically sustainable system. This would include such factors as a secure supply of suitable equipment, a competitive cost base and sufficient revenues from sales and other sources in order for the business to survive. In an attempt to examine whether a white goods re-use program could possibly operate in a competitive manner with new appliances, this study has examined examples of comparable businesses operating in the EU as well as interpreting data on consumer demand.  相似文献   

8.
Land change science has emerged as a fundamental component of global environmental change and sustainability research. Still, much remains to be learned before scientists can fully assess future roles of land-use/cover changes (LUCC) in the functioning of the Earth system and identifying conditions for sustainable land use. The objective of this paper is to gain a better understanding of the complex interactions of human and natural drivers underlying LUCC. We do so by developing and estimating a novel structural model of land use and using spatially explicit longitudinal observations from the Upper Yangtze basin of China. Our analysis focuses on the multiple dimensions of agriculture—not only cropland use itself, but also grain production, soil erosion, and related technical change—and our data cover 31 counties over four time periods from 1975 to 2000. Our results show that technical change plays an important role in supplying food on a limited cropland; limiting cropland expansion in turn reduces soil erosion, which then benefits grain production in the longer term. It is also found that policies and institutions have significant impacts on land use and the status of soil erosion. Together, these results carry some great implications to sustainable land use and ecosystem management.  相似文献   

9.
This essay interprets Cox's keynote as a call for environmental communication to reorient itself as a form of ideological criticism and identifies the potential pitfalls of heeding that call. First, the author revisits key arguments surrounding the practice of ideological criticism in Communication Studies and articulates their relevance to discussions about the mission and purpose of environmental communication. Second, he suggests that an uncritical embrace of the rationale for a “crisis discipline” may perpetuate problematic assumptions about communication, both as a social practice and as a scholarly discipline. Third, he argues that such problems may be sidestepped by making environmental crisis itself a central concept and object of environmental communication inquiry, such that environmental communication does not merely respond to crisis but becomes a discipline of and about crisis. A focus on the dynamics of crisis, the author concludes, entails a persistent concern with judgment in its political, scholarly, and pedagogical contexts.  相似文献   

10.
A meta-analysis of wetland contingent valuation studies   总被引:8,自引:1,他引:7  
There is growing interest in the potential for producing generally applicable models for valuing non-market environmental services which do not rely upon expensive and time-consuming survey work, but rather extrapolate results from previous studies. This paper presents a meta-analysis for the use and non-use values generated by wetlands across North America and Europe. The study assesses the socio-economic values attributable to the hydrological, biogeochemical and ecological functions provided by such complex environmental assets. The clustering of multiple values derived from single studies is examined through the application of multilevel modelling methods allowing for the hierarchical structure of such data. Received: 24 February 1999 · Accepted: 6 June 1999  相似文献   

11.
This paper discusses the relationship of new information and communication technologies (ICTs) and sustainable development. It deconstructs popular myths about a sustainable information society. One myth is that telework has reduced the need to travel and hence environmental pollution. The reality is that teleworkers make up only a small share of the total workforce, telework can generate new social relationships and hence the need for more travelling, work-related travel produces only a small amount of the total carbon dioxide emissions, and that the total distance travelled per employee is constantly rising. Another myth is that information economy is weightless and dematerialized which reduces environmental impacts. The energy and resource intensities of the ICT sector are indeed lower than the one of the total economy. The ICT sector also emits less CO2 than the total economy. But the ICT sector constitutes only a small portion of the total value added and fossil fuel combustion is still the dominant activity of modern industrial economies. Some stakeholders argue that virtual products allow resource, energy, and transport savings. But burning digital music on compact discs and DVDs, printing digital articles and books, etc. results in rebound effects that cause new material and energy impacts, computers have a low life span of 2–3 years, reusable and upgradeable computers and computer equipment are hardly used and might not be as profitable as non-reusable ones, computers are consuming much energy. Alternatives such as energy consumption labels on ICTs and green ICTs that consume less energy contradict dominant economic interests. A sustainable information society is a society that makes use of ICTs and knowledge for fostering a good life for all human beings of current and future generations by strengthening biological diversity, technological usability, economic wealth for all, political participation of all, and cultural wisdom. Achieving a sustainable information society costs, it demands a conscious reduction of profits by not investing in the future of capital, but the future of humans, society, and nature.  相似文献   

12.
The protection of drinking water sources is vital to urban development and public health. In this study, the current situation of the mandatory protection area for drinking water source in the Pearl River Delta region was investigated using a method combining Google Earth with the field survey. The gaps between management practices and legislation requirements were analyzed. Finally, several countermeasures for water resource protection were proposed as follows: to promote delineation in a more scientific way, to safeguard the sanctity of the law, to make better plan on water saving, and to encourage public participation in supervision and management.  相似文献   

13.
土地利用规划环境影响评价是针对土地利用的宏观结构调整与布局对环境可能造成的影响作出的预测性评估。当前我国的土地利用规划环境影响评价工作刚刚起步,国内还没有形成公认的范例,旨在通过实例研究建立一个适用于土地利用规划环境影响评价的方法。选用综合指数和协调度指标相结合的方法对贵州省毕节地区的土地利用规划环境影响进行评价,并且系统地探讨了基于该方法的评价指标体系的建立。结果表明,毕节地区土地利用规划修编方案对生态、社会和经济环境的综合影响属中等水平协调,通过适当的环境影响减缓措施加以改善即可。  相似文献   

14.
虚拟水战略:拯救民勤绿洲的新思路   总被引:11,自引:0,他引:11  
位于甘肃石羊河下游的民绿洲,水资源极度缺乏,生产、生活和生态用水矛盾突出,出现了严重的生态危机,其中湖区的生态经济系统已呈“崩溃”之势。拯救民勤绿洲成为社会广泛关注的重大问题。“虚拟水”是20世纪90年代初Tony Allan提出的一个新概念,虚拟水战略是指贫水区域通过贸易的方式从富水地区购进水资源密集型产品来获得本区水资源安全的一种构想。本文通过对节水、调水、移民等常规方案与虚拟水战略的对比分析后,认为虚拟水战略是拯救民勤绿洲的一个全新思路,探讨了虚拟水战略实施的政策建议;提出了创新区域水资源管理体制和区域经济发展思路以及建立国家生态补偿机制的主张。  相似文献   

15.
In recent years, churches across the world have become involved in dialogue on the theory and practice of sustainable development. A number of Western churches have expressed their concern about climate change and destructive living patterns, stressing the need for human beings to exercise the care for all creation based on a life of sharing and sacrifice. Some Orthodox churches, however, quite recently included the environmental issues in their agendas. While the Bases of Social Concept, a major doctrine of the Russian Orthodox Church adopted in 2000, for the first time emphasises the Churchs position in overcoming environmental crisis and presents a solid basis on which to build the future environmental strategy of the Church, the Ethiopian Orthodox Church has not yet drawn up a programme document that might serve as a framework for the Churchs current extensive activities in the field of biodiversity conservation and sustainable forestry practices. Hence, despite certain closeness of both institutions, there is the potential for strengthening their roles in promoting sustainable development, based on the Biblical concept that the Earth belongs to the Lord and humans are responsible stewards assigned the duty to work for creation and care for it. This paper seeks to demonstrate by means of comparable analysis between the two Churches, Orthodox in nature but different in rites and religious practices, that traditional, highly conservative faiths may serve as powerful instruments of spreading out the ideas of sustainable development as the basis of spiritual revival in the situation of the two concurrent and interrelated crises – spiritual and ecological.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.
Much of the widespread poverty, environmental desecration, and waste of human life seen around the globe could be prevented by known (to humanity as a whole) technologies, many of which are simply not available to those that need it. This lack of access to critical information for sustainable development is directly responsible for a morally and ethically unacceptable level of human suffering and death. A solution to this general problem is the concept of open source appropriate technology or OSAT, which refers to technologies that provide for sustainable development while being designed in the same fashion as free and open source software. OSAT is made up of technologies that are easily and economically utilized from readily available resources by local communities to meet their needs and must meet the boundary conditions set by environmental, cultural, economic, and educational resource constraints of the local community. This paper explores both the open source and appropriate technology aspects of OSAT to create a paradigm, in which anyone can both learn how to make and use needed technologies free of intellectual property concerns. At the same time, anyone can also add to the collective open source knowledge ecosystem or knowledge commons by contributing ideas, designs, observations, experimental data, deployment logs, etc. It is argued that if OSAT continues to grow and takes hold globally creating a vibrant virtual community to share technology plans and experiences, a new technological revolution built on a dispersed network of innovators working together to create a just sustainable world is possible.  相似文献   

17.
The detection of illicit drugs in environmental matrices may be a cause for concern, both from the perspective of their potential environmental impacts and the fact that their presence in detectable concentrations would be an indicator of significant drug use. The primary goal behind recent studies on this subject has been to use measured influent concentrations of selected illicit drugs or their in vivo metabolites in the environment as a means of estimating the abuse level of these drugs and patterns of consumption. Thus-far, such calculations have hinged on the use of solitary excretion estimates from single studies of limited scope and/or studies of limited applicability. Therefore, the need exists to conduct a comprehensive meta-analysis of metabolic disposition studies to construct excretions profiles for the various illicit drugs and their in vivo metabolites. The constructed excretory profiles should not only provide mean excretion values but also indicate the expected variations in excreted fractions that arise due to differences not only in the metabolic capacity of users but also in the efficiencies of various routes of administration for a given illicit drug. Therefore, the primary goal of the research presented here was to refine sewer epidemiology extrapolation mass balances for various illicit drugs of interest by constructing their excretory profiles segregated by route-of-administration. After conducting such a study with a multi-national scope on illicit drugs including cocaine, heroin and ecstasy, the results obtained clearly indicate that extrapolation factors currently being used in literature for these drugs to enumerate prevalence of abuse required significant refinement to increase their reliability.  相似文献   

18.
Enchytraeids are important organisms of the soil biocenosis. They improve the soil pore structure and the degradation of organic matter. These organisms are used in standardized testing, using survival and reproduction (6 weeks) as endpoints. The use of biomarkers, linked to ecologically relevant alterations at higher levels of biological organization, is a promising tool for Environmental Risk Assessment. Here, enchytraeids were exposed for different time periods (two days and three weeks) to different soils (OECD artificial soil, different compositions in its organic matter, clay or pH value, and LUFA 2.2 natural soil) and different chemicals (Phenmedipham and copper). The main question addressed in the present study was if the effects of chemicals and different soil properties are preceded by alterations at the sub-cellular level, and if these endpoints may be used reliantly as faster screening tools for the assessment of different stress conditions in soils. The parameters measured in E. albidus whole body were: lipid peroxidation (LPO), total glutathione (TG), as well as the enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST). The results showed that biomarker responses in E. albidus were significantly affected by the soil type (GST, CAT, GPx, GR and LPO) and the duration of exposure in OECD artificial soil (GST, GPx, GR, CAT and LPO) but not in LUFA 2.2 natural soil. For the abiotic factors studied, after 2 days, low pH decreased significantly the TG levels and the activities of CAT and GR,and low OM also significantly decreased CAT and GR activities. After 3 weeks, differences in soil properties caused a decrease in GR and GPx activities, whereas increased GST activity was observed due to low organic matter and pH. Copper significantly increased the activities of CAT, GPx and GR, and decreased the activity of GST after 2 days as well as inscreasing LPO levels after 3 weeks. Phenmedipham increased LPO levels, associated with increased levels of TG as well as increased activities of CAT and GPx and decreased GST activity after 3 weeks exposure. This study shows that both abiotic and chemical stresses could be followed through biomarker analysis and that some of these determinations are potential endpoints in a quick soil contamination assessment procedure.  相似文献   

19.
Chromium toxicity in plants   总被引:56,自引:0,他引:56  
Due to its wide industrial use, chromium is considered a serious environmental pollutant. Contamination of soil and water by chromium (Cr) is of recent concern. Toxicity of Cr to plants depends on its valence state: Cr(VI) is highly toxic and mobile whereas Cr(III) is less toxic. Since plants lack a specific transport system for Cr, it is taken up by carriers of essential ions such as sulfate or iron. Toxic effects of Cr on plant growth and development include alterations in the germination process as well as in the growth of roots, stems and leaves, which may affect total dry matter production and yield. Cr also causes deleterious effects on plant physiological processes such as photosynthesis, water relations and mineral nutrition. Metabolic alterations by Cr exposure have also been described in plants either by a direct effect on enzymes or other metabolites or by its ability to generate reactive oxygen species which may cause oxidative stress. The potential of plants with the capacity to accumulate or to stabilize Cr compounds for bioremediation of Cr contamination has gained interest in recent years.  相似文献   

20.
虚拟耕地资源被广泛认为是缓解国内耕地资源压力和促进农业经济增长的重要举措之一。在论证虚拟耕地资源贸易对农业经济增长作用机理分析的基础上,计算1996~2018年中国主要农产品虚拟耕地资源贸易量,并对虚拟耕地资源对农业经济增长中的贡献份额进行实证分析,为调整对外贸易战略及优化耕地资源策略提供参考。结果表明:虚拟耕地资源可以在更大范围内实现耕地资源的优化配置;主要农产品贸易的巨大逆差决定了中国是虚拟耕地资源净进口大国,其中,油料是虚拟耕地资源净进口量最大的品种;虚拟耕地资源对农业经济增长的贡献率为0.26%,观点得到了佐证。同时,还提出了要试点实施虚拟耕地资源,全力以赴做好贸易政策调整战略;充分利用国内外“两种资源、两个市场”,倒逼主要农产品进行结构调整;努力构建虚拟耕地资源管理新模式,推动农业“走出去”与市场多元化结合等政策建议。  相似文献   

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