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1.
To comply with EU recycling targets for packaging waste, the UK relies on an industry run and market based eco-tax levied by reprocessors on obligated businesses. After examining the details of this approach, the use of Packaging Waste Recovery Notes is assessed in terms of its allocative impact and the contribution made to eco-efficiency. The evidence indicates the UK system has minimized the cost of delivering current EU targets, but has not been able to deliver allocative efficiency or to demonstrate dynamic improvements in resource use. Its effectiveness in meeting impending higher targets remains open to question.  相似文献   
2.
An Erratum has been published for this article in Remediation 14(4) 2004, 141. The selection of remediation options for the management of unacceptable risks at contaminated sites is hindered by insufficient information on their performance under different site conditions. Therefore, there is a need to define “operating windows” for individual remediation options to summarize their performance under a variety of site conditions. The concept of the “operating window” has been applied as both a performance optimization tool and decision support tool in a number of different industries. Remediation‐option operating windows could be used as decision support tools during the “options appraisal” stage of the Model Procedures (CLR 11), proposed by the Environment Agency (EA) for England and Wales, to enhance the identification of “feasible remediation options” for “relevant pollutant linkages.” The development of remediation‐option operating windows involves: 1) the determination of relationships between site conditions (“critical variables”) and option performance parameters (e.g., contaminant degradation or removal rates) and 2) the identification of upper‐ and lower‐limit values (“operational limits”) for these variables that define the ranges of site conditions over which option performance is likely to be sufficient (the “operating window”) and insufficient (the “operating wall”) for managing risk. Some research has used case study data to determine relationships between critical variables and subsurface natural attenuation (NA) process rates. Despite the various challenges associated with the approach, these studies suggest that available case study data can be used to develop operating windows for monitored natural attenuation (MNA) and, indeed, other remediation options. It is envisaged that the development of remediation‐option operating windows will encourage the application of more innovative remediation options as opposed to excavation and disposal to landfill and/or on‐site containment, which remain the most commonly employed options in many countries. © 2004 Wiley Periodicals, Inc.  相似文献   
3.
Model estimates of NOy and NHx deposition across Britain for 1996 (5 km square resolution) were applied as explanatory variables to account for national-scale, fine-grained changes in plant species composition between 1990 and 1998. Plant species data were recorded from up to 27 fixed plots located within a stratified random sample of 596 1 km2. The response variable was a cover-weighted Ellenberg fertility score for each plot. Analyses were carried out separately for woodlands, semi-natural grasslands and heaths/bogs. Most of the variation in the botanical response variable occurred between plots within squares and so could not be explained by the model deposition data. NHx deposition estimates accounted for significant, but small components of between 1 km2 variation in the change in Ellenberg score in grasslands (5.6%) and heath/bogs (9.8%) but not woodlands. NOy deposition estimates were not significantly associated with vegetation change. Linear models provided the best fit and the slope of the relationship was lower for heath/bogs than grasslands. Further signal attribution at sub-kilometre square scales requires the development of fine-grained models of N deposition that can be generalised across regional sampling domains.  相似文献   
4.
Using resource-monitoring data from seven protected areas, the effectiveness of three campfire policies—campfire ban, designated campfires, and unregulated campfires—were assessed based on the number of fire sites and the amount of tree damage. Results indicate that unregulated campfire policies permitted substantial numbers of fire sites and tree damage in campsites, although fire bans did not eliminate or even substantially decrease these problems. A designated campfire policy was effective in decreasing number of fire sites, but little difference was found among policies regarding tree damage. Given the importance of campfires to visitor experiences, campfire prohibitions could be viewed as unnecessarily restrictive based on their limited success in preventing resource damage. Conclusions encourage protected-area managers to consider designated campfire policies and prohibitions on axes, hatchets, and saws to better meet resource protection and visitor experience mandates.  相似文献   
5.
Methods are presented to extract intra-seasonal meteorological patterns at three scales to explain 24-h fine particulate matter (PM2.5) pollution events: evolving large-scale meteorological scenarios, synoptic regimes driving diurnal variability near the surface, and localized meteorological triggers. The methods were applied to understand how winter weather conditions impacted PM2.5 around the San Francisco Bay Area (SFBA). Analyzing data across 12 winters (November–March) ensured robust characterization of the SFBA conditions. SFBA 24-h PM2.5 exceedances (35 μg m?3) required several simultaneous characteristics: a ridge of aloft high pressure moving over SFBA, providing weak surface pressure gradients over Central California; persistent easterly flows through SFBA extending vertically to around the 925-hPa pressure level; orographically channeled winds resulting from stability; enhanced nocturnal cooling under clear-sky conditions providing for enhanced drainage flows off the Central California slopes; and at least two consecutive days of these conditions.  相似文献   
6.
Regional Environmental Change - Louisiana faces extensive coastal land loss which threatens the livelihoods of marginalized populations. These groups have endured extreme disruptive events in the...  相似文献   
7.
Regional Environmental Change - Research that projects biophysical changes under climate change is more advanced than research that projects socio-economic changes. There is a need in adaptation...  相似文献   
8.
This paper investigates multi-stakeholder arrangements initiated by businesses and NGOs from the North that aim to enhance a more sustainable agricultural production at specific localities in Southern countries. We aim to better understand the search for concerted action in multi-actor arrangements. Therefore, this paper presents a diagnostic framework with three strategic challenges the partnership projects are facing: linking global economic objectives to local needs, values and interests; bridging public and private interests and responsibilities; and seeking trade-offs between social, environmental and economic values. Starting from the partnerships’ Theory of Change, this diagnostic framework is applied to comparative case studies of partnership projects in the cocoa sector in Indonesia, which are part of a Northern-based public–private partnership to improve farmers’ prospective. It is concluded that the economic reality faced by the farmers differs from that of the Northern actors; collaboration with governments is difficult because of different organizational cultures; and the partnership projects underestimate the strength of vested social relations the smallholders are part of. Overall, the initiators of the partnerships seem to work with a too restricted economic interpretation of the local reality.  相似文献   
9.
This study examined the influencing factors of the self-reported behavioral intentions toward genetically modified (GM) crops using a multi-stakeholder approach in the Khuzestan Province in Southwest Iran. The study focused on three different groups, including: “agricultural students,” “agricultural private firms’ managers” and “rich-resource farmers.” Data were collected using a researcher-made questionnaire and was analyzed by SPSS (V20) and AMOS (V20). Results indicated that the respondents perceive more benefits than risks for GM crops and that the perception of benefits and risks, respectively, had positive and negative impacts on the self-reported behavioral intention of the respondents. The knowledge of the respondents regarding these crops had positive impacts on perception of benefits. The results showed that both managers and students worried about the food safety and impact of GM crops on human health while farmers worried about the environmental risks of GM crops. The results also revealed that those who are the most conscious about GM crops are more trusted. The findings also showed that the majority of the respondents hold a positive view of the potential of GM crops.  相似文献   
10.
The Barind tract of West Bengal is an area of tropical sub-humid region composed of old alluvial soil. The area has high water demand due to growing population pressure and intensification in agricultural activity. These create huge stress on surface and ground water availability. Continuous withdrawal of ground water has become an alternative source of irrigation water which has also again made the condition critical. Ground water level has been lowered down drastically in many parts in this region. Under this circumstance, it is necessary to delineate potential ground water-bearing layers. Therefore, the present study attempts to identify potential ground water-bearing zones to manage ground water effectively. Instead of usually used parameters for ground water potentiality delineation here only some particular litholog parameters like breadth of water-bearing layer, depth of water-bearing layer, presence of clay layer above or below major water-bearing layer have been considered for delimiting the same. The result shows that out of total area, 60% area (405,382.2 ha) falls under very low to low potential ground water-bearing zone and only 8.19% area (55,634.97 ha) is potential. Considering this spatial pattern of ground water availability, harvesting structure and magnitude of water withdrawing should be designed.  相似文献   
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