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971.
This paper aims to measure raw material inputs and waste flows in an Irish city-region in order to analyse (i) whether there was absolute dematerialisation in the particular case study over the period 1992–2002 and (ii) whether material consumption and waste generation were decoupled from economic growth and increases in disposable income over the same period. It was found that the selected material flow indicators showed no evidence of absolute dematerialisation over the given study period, although more recent evidence at the national level suggests that a decline in construction activity and extraction of non-metallic minerals has resulted in an absolute reduction in material consumption and it is likely that this will be mirrored at the system boundary level.It was found that Domestic Material Consumption (DMC) per capita and Direct Material Input (DMI) per capita increased at a faster rate than Domestic Processed Output (DPO) per capita and Direct Material Output (DMO) per capita between 1992 and 2002, which indicates relative decoupling of consumption from waste generation. In addition, it was found that there was relative decoupling of consumption and waste generation from disposable income growth over the study period. Finally, it was found that average DMC and DMI figures for the selected case study were lower than the national averages but broadly similar to results for other city-regions in the European Union (EU). On a methodological note, it was concluded that material flow accounting (MFA) for city-regions in Ireland is constrained due to a lack of disaggregated data for material flows, with the exception of local waste data, and it is recommended that bottom-up analysis should be used to complement disaggregated top-down data.  相似文献   
972.
973.
974.
Abstract: Water demand in a viable economy tends to be dynamic: it changes over time in response to growth, drought, and social policy. Institutional capacity to re‐allocate water between users and uses under stress from multiple sources is a key concern. Climate change threatens to add to those stresses in snowmelt systems by changing the timing of runoff and possibly increasing the severity and duration of drought. This article examines Snake and Klamath River institutions for their ability to resolve conflict induced by demand growth, drought, and environmental constraints on water use. The study finds that private ownership of water rights has been a major positive factor in successful adaptation, by providing the basis for water marketing and by promoting the use of negotiation and markets rather than politics to resolve water conflict.  相似文献   
975.
Abstract: The Crown of the Continent is one of the premiere ecosystems in North America containing Waterton‐Glacier International Peace Park, the Bob Marshall‐Great Bear‐Scapegoat Wilderness Complex in Montana, various Provincial Parks in British Columbia and Alberta, several national and state forest lands in the USA, and Crown Lands in Canada. The region is also the headwater source for three of the continent’s great rivers: Columbia, Missouri and Saskatchewan that flow to the Pacific, Atlantic and Arctic Oceans, respectively. Headwaters originate in high elevation alpine environs characterized by high snow accumulations in winter and rainstorms in summer. Most headwaters of the region contain high quality waters with few ions in solution and extremely low nutrient concentrations. Alpine streams have few species of aquatic organisms; however, they often possess rare species and have hydrogeomorphic features that make them vulnerable to climatic change. Subalpine and valley bottom streams of the Crown of the Continent Ecosystem (CCE) flow through well forested watersheds. Along the elevation gradient, the streams and rivers of the CCE flow through series of confining and nonconfining valleys resulting in distinct canyon and floodplain reaches. The alluvial floodplains are characterized by high species diversity and bioproduction maintained by the hydrologic linkages of habitats. The streams and rivers of the CCE have low nutrient concentrations, but may be significantly affected by wildfire, various resource extraction activities, such as logging or mining and exurban encroachment. Wildfire has been shown to increase nutrient loading in streams, both during a fire and then following the fire for as much as 5 years. Logging practices increase nutrient loading and the algal productivity of stream periphyton. Logging and associated roads are also known to increase sediment transport into Crown of the Continent streams directly affecting spawning success of native trout. The CCE is one of the fastest growing regions in the USA because of the many recreational amenities of the region. And, while the region has many remarkably pristine headwater streams and receiving rivers, there are many pending threats to water quality and quantity. One of the most urgent threats comes from the coal and gas fields in the northern part of the Crown of the Continent, where coal deposits are proposed for mountain‐top removal and open‐pit mining operations. This will have significant effects on the waters of the region, its native plants and animals and quality of life of the people.  相似文献   
976.
977.
The geological storage of carbon dioxide is currently being considered as a possible technology for reducing emissions to atmosphere. Although there are several operational sites where carbon dioxide is stored in this way, methods for assessing the long-term performance and safety of geological storage are at an early stage of development. In this paper the similarities and differences between this field and the geological disposal of radioactive wastes are considered. Priorities are suggested for the development of performance assessment methods for carbon dioxide storage based on areas where experience from radioactive waste disposal can be usefully applied. These include, inter alia, dealing with the various types of uncertainty, using systematic methodologies to ensure an auditable and transparent assessment process, developing whole system models and gaining confidence to model the long-term system evolution by considering information from natural systems. An important area of data shortage remains the potential impacts on humans and ecosystems.  相似文献   
978.
Occupational low back pain (LBP) remains a leading safety and health challenge. This cross-sectional investigation measured the prevalence of LBP in residential carpenters and investigated ergonomic risk factors. Ninety-four carpenters were investigated for LBP presence and associated risk factors. Ten representative job-tasks were evaluated using the Ovako Working Posture Analysis System (OWAS) and ErgoMaster 2D software to measure elements of posture, stress, and risk. Job-tasks were found to differ significantly for total lumbar compression and shear at peak loading (p < .001), ranging from 2 956 to 8 606 N and 802 to 1 974 N respectively. OWAS indicated that slight risk for injury was found in 10 job-tasks while distinct risk was found in 7 of the 10 job-tasks. Seven of the 10 job-tasks exceeded the National Institute for Occupational Safety and Health (NIOSH) action limit of 3 400 N for low back loading. The point prevalence for LBP was 14% while the annual prevalence was 38%.  相似文献   
979.
Gradient analyses were used to correlatively determine the importance of acid-related variables for littoral macroinvertebrate assemblages. To better ascertain the effects of acidity on macroinvertebrate assemblages we removed sites judged to be affected by other stressors such as agriculture, urbanization and liming. PCA of land use and water chemistry confirmed the presence of an acidity gradient; several acidity variables (e.g. pH and buffering capacity) were strongly correlated with the first PC axis, which explained Ca 32% of the variance in the environmental data. Partial constrained ordination of littoral macroinvertebrate assemblages with water chemistry, after removing the effect of other confounding variables (e.g. land use/type), showed that acidity variables accounted for significant amounts of among-lake variability in assemblage structure. Regression of canonical scores (a metric of community composition) and diversity with pH and alkalinity was used to visually determine ecological breakpoints or threshold values. Five classes were established for pH: pH?<?5 (extremely acid), 5?<?pH?≤?5.6 (very acid), 5.6?<?pH?≤?6.2 (acid), 6.2?<?pH?≤?6.8 (weakly acid) and pH?>?6.8 (neutral-alkaline). Similarly, three classes were determined for alkalinity/acidity: <0.02, 0.02–0.1 and >0.1 meq/L.  相似文献   
980.
Determinants of consumer behavior related to organic foods   总被引:1,自引:0,他引:1  
Shepherd R  Magnusson M  Sjödén PO 《Ambio》2005,34(4-5):352-359
There have been many studies of what influences consumers in their decisions to purchase or consume organic foods, mainly concerned with fresh organic foods. These show a discrepancy between attitudes and behavior with people being positive about organic foods but often not purchasing them. This discrepancy seems to be explained by the fact that consumers do not consider "organically produced" to be an important purchase criterion, that organic foods are not perceived to surpass conventional foods regarding taste and shelf life (two qualities rated to be of great importance), and because of the perceived premium prices of organic foods. In two Swedish studies, health benefits were demonstrated to be more strongly related to attitudes and behavior toward organic foods than were perceived environmental benefits. A new European Union (EU) project will investigate the influences on both fresh and processed organic foods and investigate the role of moral, ethical, and affective influences on choice across eight EU countries.  相似文献   
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