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261.
At the centre of the debate surrounding sustainable development is a recognition that companies can make a major contribution by being environmentally and socially responsible and that tools associated with these concepts can enhance the competitiveness and economic performance of the firm. In this paper we go further in arguing that in a world of globalisation it is equally important to look at issues of international trade.

In an examination of free trade we argue that it is neither fully consistent with sustainable development nor to the benefit of business. We point to a new imperative to develop sound sourcing, and equitable and fair trading relationships. We identify issues associated with fair trade (including issues of human rights, fair wages, sustainability reporting procedures and codes of conduct on ethics) and associated tools of analysis (guaranteed prices, codes of conduct and end price audits).

The paper argues that in a world of globalisation with greater transparency and information availability it will be important for companies to be clear about their policies on supply chain management and trade. Indeed, with the growth of an active and sophisticated civil society, it will be argued that policies associated with sound sourcing, equitable trade and fair trade could provide companies with a new competitive strategy based on ethical standards communicated to the consumer through a strategy of differentiation. We explore strategies for the integration of fair trade policies, strategies and standards, and the opportunities for new markets and niches that this presents. It is argued that the integration of fair trade into a business strategy can enhance competitiveness.  相似文献   
262.
This paper examines the problem of measuring sustainable governance in the European Union (EU-27) through the use of duality and the Slutsky equation. The proposed methodology is based on the application of a three-dimensional optimisation model, where the arguments of the objective (sustainable social welfare) function are economic goods that contribute to sustainable economic growth; environmental goods that provide for sustainable environmental protection; and social goods through which sustainable social development is achieved. The dual problem, formulated through this three-dimensional theoretical model, is solved to find the optimal solution, indicating a certain sustainability level. We suggest that this solution can be used for calculating the value of what we define here as the sustainable governmental policy indicator, which is considered to provide quantitative measurement of government policies on sustainable development within the context of ‘good governance’. Furthermore, it is suggested that the Slutsky equation can be used as a reliable method for long-term monitoring and planning of national as well as international good governance with regard to sustainable development policies. In its empirical part, the paper applies the theoretical model in an analysis of the sustainable development indicators (as set out in the Sustainable Development Strategy (SDS) of the EU) in Bulgaria for the period 2000–2010 and compares them to those of the EU-27.  相似文献   
263.
Seventeen immature green turtles Chelonia mydas were tracked concurrently by automated ultrasonic receivers at a coral reef off North-Eastern Australia (September–December 2010, 16.4°S, 145.6°E). The majority (n = 11) were tracked for the entire 100-day study, the remainder for 23–85 days. Detection data aggregated at 30-min intervals produced median 6.5–35 daily locations for individual turtles. Home range areas (95 % utilisation distribution) were ≤1 km2, $ {\bar{\text{x}}} $  ± SD = 0.74 km2 ± 0.159. To the best of our knowledge, these are the first home range estimates for C. mydas foraging at offshore tropical reefs. The findings are important for conservation in revealing near-continuous presence of the same individuals within a small geographic area. Time between detections was very short (median <3 min) demonstrating passive ultrasonic technology can track multiple turtles in a foraging environment with higher temporal resolution than typically achieved by satellite tracking.  相似文献   
264.
Although some sectors have made significant progress in learning from failure, there is currently limited consensus on how a similar transition could best be achieved in conservation and what is required to facilitate this. One of the key enabling conditions for other sectors is a widely accepted and standardized classification system for identifying and analyzing root causes of failure. We devised a comprehensive taxonomy of root causes of failure affecting conservation projects. To develop this, we solicited examples of real-life conservation efforts that were deemed to have failed in some way, identified their underlying root causes of failure, and used these to develop a generic, 3-tier taxonomy of the ways in which projects fail, at the top of which are 6 overarching cause categories that are further divided into midlevel cause categories and specific root causes. We tested the taxonomy by asking conservation practitioners to use it to classify the causes of failure for conservation efforts they had been involved in. No significant gaps or redundancies were identified during this testing phase. We then analyzed the frequency that particular root causes were encountered by projects within this test sample, which suggested that some root causes were more likely to be encountered than others and that a small number of root causes were more likely to be encountered by projects implementing particular types of conservation action. Our taxonomy could be used to improve identification, analysis, and subsequent learning from failed conservation efforts, address some of the barriers that currently limit the ability of conservation practitioners to learn from failure, and contribute to establishing an effective culture of learning from failure within conservation.  相似文献   
265.
A passively vented landfill site in Northern Germany was monitored for gas emission dynamics through high resolution measurements of landfill gas pressure, flow rate and composition as well as atmospheric pressure and temperature. Landfill gas emission could be directly related to atmospheric pressure changes on all scales as induced by the autooscillation of air, diurnal variations and the passage of pressure highs and lows. Gas flux reversed every 20 h on average, with 50% of emission phases lasting only 10h or less. During gas emission phases, methane loads fed to a connected methane oxidising biofiltration unit varied between near zero and 247 g CH4 h(-1)m(-3) filter material. Emission dynamics not only influenced the amount of methane fed to the biofilter but also the establishment of gas composition profiles within the biofilter, thus being of high relevance for biofilter operation. The duration of the gas emission phase emerged as most significant variable for the distribution of landfill gas components within the biofilter.  相似文献   
266.
Economic, environmental, and social limits of the current capitalist mode of production have led to a rethinking and reconceptualisation of economic processes and models including the role of businesses in sustainable development. While green economies and more specifically green entrepreneurs have been identified as agents of change that can challenge the mainstream and seek to induce environmental, social, and ethical transformation of society, much research has stayed within existing models of thinking predominantly rooted in technocratic approaches (e.g. ecological modernisation and more recently transition studies). This paper seeks to offer an alternative understanding of green entrepreneurship that breaks open these discussions using an environmental justice frame that focuses on the role of extra-economic discourses in shaping the social relations of economic systems. By drawing on an exemplary case study of “just” entrepreneurship from Boston, Massachusetts, USA, the paper seeks to start a conversation around the ideas of green entrepreneurship and environmental justice as vehicles to deliver potentially broader system changes and explores both conceptual and practical aspects of green development. As such, it offers (1) evidence of a just green economy that can be realised within existing capitalist structures as well as (2) a different conceptual entry point to understanding green entrepreneurship.  相似文献   
267.
268.
Silver nanoparticles: behaviour and effects in the aquatic environment   总被引:3,自引:0,他引:3  
This review summarises and evaluates the present knowledge on the behaviour, the biological effects and the routes of uptake of silver nanoparticles (Ag NPs) to organisms, with considerations on the nanoparticle physicochemistry in the ecotoxicity testing systems used. Different types of Ag NP syntheses, characterisation techniques and predicted current and future concentrations in the environment are also outlined. Rapid progress in this area has been made over the last few years, but there is still a critical lack of understanding of the need for characterisation and synthesis in environmental and ecotoxicological studies. Concentration and form of nanomaterials in the environment are difficult to quantify and methodological progress is needed, although sophisticated exposure models show that predicted environmental concentrations (PECs) for Ag NPs in different environmental compartments are at the range of ng L(-1) to mg kg(-1). The ecotoxicological literature shows that concentrations of Ag NPs below the current and future PECs, as low as just a few ng L(-1), can affect prokaryotes, invertebrates and fish indicating a significant potential, though poorly characterised, risk to the environment. Mechanisms of toxicity are still poorly understood although it seems clear that in some cases nanoscale specific properties may cause biouptake and toxicity over and above that caused by the dissolved Ag ion. This review concludes with a set of recommendations for the advancement of understanding of the role of nanoscale silver in environmental and ecotoxicological research.  相似文献   
269.
Abstract: Differences in the storm‐event responses of dissolved organic carbon (DOC) and nitrogen (DON) in streamflow and ground water were evaluated for a glaciated forested watershed in western New York. Eight to ten storm events with varying rainfall amounts, intensities, and antecedent moisture conditions were studied for three catchments (1.6, 3.4, and 696 ha) over a three‐year period (2003‐2005). Concentrations of DOC in streamflow exiting the catchments were significantly higher for storm events following a dry period, whereas no similar response was observed for DON. Highest DON concentrations in streamflow were typically associated with storm events following wet antecedent moisture conditions. In addition to antecedent moisture conditions, DOC concentrations were also positively correlated with precipitation amounts, while DON did not reveal a consistent pattern. Streamwater and ground‐water concentrations of DOC during storm events were also strongly correlated with riparian ground‐water depths but a similar relationship was not observed for DON. Ground‐water DON concentrations were also more variable than DOC. We hypothesized that the differences in DOC and DON responses stemmed from the differences in catchment sources of these solutes. This study suggests that while DOC and DON are intrinsically linked as components of dissolved organic matter, their dynamics and exports from watersheds may be regulated by a different set of mechanisms and factors. Identifying these differences is critical for developing more reliable and robust models for transport of dissolved organic matter.  相似文献   
270.
Nitrogen deposition is a continuing problem in European alpine regions. We hypothesised that, despite climatic limitations, low-alpine Calluna heathland would respond to nitrogen addition with increased shoot growth and flowering and that fire and grazing would modify responses. In a five-year study, 0-50kgNha(-1)y(-1) were added, combined with burning (+/-) and clipping (+/-). Calluna vulgaris responded with increased shoot extension, but effects on flowering were variable. Burning enhanced the positive effect of nitrogen addition and negative effects of clipping. Sub-dominant shrubs generally did not respond to nitrogen. C. vulgaris shoot extension was stimulated by nitrogen addition of 10kgNha(-1)y(-1) (above background) supporting suggestions that alpine heathlands are sensitive to low levels of nitrogen deposition. Increased C. vulgaris growth could negatively impact on important lichen components of this vegetation through increased shading and competition. Climatic factors constrain productivity in this community, but do not prevent rapid responses to nitrogen deposition by some species.  相似文献   
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