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831.
ABSTRACT: The use of transferable discharge permits in water pollution, what we will call water quality trading (WQT), is rapidly growing in the U.S. This paper reviews the current status of WQT nationally and discusses the structures of the markets that have been formed. Four main structures are observed in such markets: exchanges, bilateral negotiations, clearinghouses, and sole source offsets. The goals of a WQT program are environmental quality and cost effectiveness. In designing a WQT market, policy makers are constrained by legal restrictions and the physical characteristics of the pollution problem. The choices that must be made include how trading will be authorized, monitored and enforced. How these questions are answered will help determine both the extent to which these goals are achieved, and the market structures that can arise. After discussing the characteristics of different market structures, we evaluate how this framework applies in the case of California's Grassland Drainage Area Tradable Loads Program.  相似文献   
832.
We used a prospective design and structural equation modeling procedures to examine the processes by which people internalize the doing of new environmental behaviors. As predicted by self-determination theory (Deci & Ryan, 1985: Intrinsic Motivation and Self-determination in Human Behaviour, Plenum, New York; Deci & Ryan, 2000: Psychol. Inquiry 11, 227), participants who perceived the experimenter as autonomy-supportive evidenced greater internalized motivation regarding a set of self-selected environmental goals. Internalized motivation in turn predicted goal performance during the following week, which in turn predicted intentions to keep on striving after the study was over. Implications for the question of how to motivate people to engage in more environmentally responsible behavior are discussed.  相似文献   
833.
Photo-oxidation and Photo-toxicity of Crude and Refined Oils   总被引:2,自引:0,他引:2  
The fate and effects of an oil spill are effected by solar radiation through the action of photo-oxidation and photo-toxicity. Photo-oxidation, an important process in the weathering of oil, produces a variety of oxidized compounds, including aliphatic and aromatic ketones, aldehydes, carboxylic acids, fatty acids, esters, epoxides, sulfoxides, sulfones, phenols, anhydrides, quinones and aliphatic and aromatic alcohols. Some of these compounds contribute to the marine biota toxicity observed after an oil spill. Photo-toxicity occurs when uptake of certain petroleum compounds, e.g. certain polycyclic aromatic hydrocarbons and benzothiophenes, is followed by solar exposure which results in much greater toxicity than after dark uptake. The mechanism of PAH photo-toxicity includes absorbance of solar radiation by the PAH which produces a free radical and this free radical in turn reacts with oxygen to produce reactive oxygen species that can damage DNA and other cellular macromolecules. While most studies on photo-toxicity have been carried out in the laboratory, there are studies showing that water from an oil spill is photo-toxic to bivalve embryos for at least a few days after the spill. Other studies have found that oil contaminated sediments are photo-toxic to several marine invertebrates. More studies are required to determine if marine fauna at an oil spill site are effected by the action of photo-toxicity and photo-oxidation.  相似文献   
834.
Self‐efficacy belief is a significant predictor of behavioral choices in terms of goal setting, the amount of effort devoted to a particular task, and actual performance. This study conceives of formation and change of self‐efficacy as a social and context‐dependent process. We hypothesized that different group factors (discretionary and ambient group stimuli) influence changes in members' self‐efficacy through differing routes (individual‐level and cross‐level processes). We tested our hypotheses using data from individuals in 169 training groups who attended a 5‐day workshop designed to increase participants' job‐search skills and efficacy. Specifically, we examined the degree of change in participants' job‐search efficacy before and after the workshop. The results showed that (a) membership diversity in education was positively related to increases in job‐search efficacy, (b) supportive leadership contributed to job‐search efficacy at the individual level of analysis with no cross‐level effects, and (c) open group climate contributed to job‐search efficacy through both individual‐level and cross‐level processes. Limitations and directions for future research are discussed. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
835.
ABSTRACT: Fifty‐four Wisconsin wetlands were surveyed in spring 1996 to determine relationships between macroinvertebrate community structure and a suite of 11 environmental attributes. Canonical correspondence analysis (CCA) showed that, after alkalinity, hydroperiod was the next most significant environmental factor influencing macroinvertebrate community structure within the wetlands sampled. CCA and direct gradient biplots were used to identify indicator taxa characteristic of the spring macroinvertebrate communities in persistent and ephemeral wetlands, and taxa characteristic of semi‐terrestrial habitats adjacent to wetlands. Two models were developed to permit the prediction of a wetland's hydroperiod class. One model assigns a range of probabilities that a wetland has a hydroperiod longer or shorter than eight months based on the occurrence or abundance of fairy shrimp, mayflies, scuds, mosquitoes, and phantom midges. A second model predicts that a wetland's hydroperiod is longer or shorter than five months based on the joint occurrences of seven persistent indicator taxa. Data used in both models were derived from a rapid bioassessment of three shoreline D‐frame net sweeps. The use of a coarse level taxonomic identification (primarily order and family) allows the approach to be performed in the field or laboratory. The macroinvertebrate models allow a manager to estimate a wetland's hydroperiod when long term water duration records do not exist. This ability is important to water resource managers because hydroperiod classification (i.e., water permanency) is one criterion used in differentiating wetlands from lakes in Wisconsin and because Wisconsin's legal system affords lakes substantially greater protection than wetlands.  相似文献   
836.
The linear production of consumer goods is characterised by mass manufacture by multinational enterprises and globally dispersed supply chains. The current centralised model has created a distance between the manufacturer and end user, limiting the opportunity for intelligent circular approaches for production and consumption. Through a mixed method approach, opportunities of circularity are explored for the consumer goods sector. The study presents four lenses to analyse three enterprises through a multi-case study approach to explore the potential of digital intelligence and redistributed manufacturing (RDM) as enablers of circular business models. In addition, the study examines whether Discrete Event Simulation can be used to evaluate the circular scenarios identified through quantifying flows of material that determine traditional economic value (cost/tonne). The mixed method approach demonstrates that, a qualitative systemic analysis can reveal opportunities for circularity, gained through implementing ‘digital intelligence’ and distributed models of production and consumption. Furthermore, simulations can provide a quantified evaluation on the effects of introducing circular activities across a supply chain.  相似文献   
837.
Directional drilling has been used for a variety of purposes, including utilities, dewatering, and remedial activities. Using this method for site cleanup versus traditional vertical extraction wells needs to be considered based upon today's remedial challenges. Traditionally, it has been stated that a single horizontal well can substitute for up to 11 vertical wells. This “rule” is arbitrary, since length and depth of the plume, surface access, and hydrogeological conditions must be considered. A better way to evaluate the cost‐benefit of a horizontal versus vertical well system is a predicted zone of influence using a mathematical and hydrogeological approach, as described herein.  相似文献   
838.
Densely populated coastal urban areas are often exposed to multiple hazards, in particular floods and storms. Flood defenses and other engineering measures contribute to the mitigation of flood hazards, but a holistic approach to flood risk management should consider other interventions from the human side, including warning information, adaptive behavior, people/property evacuation, and the multilateral relief in local communities. There are few simulation approaches to consider these factors, and these typically focus on collective human actions. This paper presents an agent-based model that simulates flood response preferences and actions taken within individual households to reduce flood losses. The model implements a human response framework in which agents assess different flood scenarios according to warning information and decide whether and how much they invest in response measures to reduce potential inundation damages. A case study has been carried out in the Ng Tung River basin, an urbanized watershed in northern Hong Kong. Adopting a digital elevation model (DEM) as the modeling environment and a building map of household locations in the case area, the model considers the characteristics of households and the flood response behavior of their occupants. We found that property value, warning information, and storm conditions all influence household losses, with downstream and high density areas being particularly vulnerable. Results further indicate (i) that a flood warning system, which provides timely, accurate, and broad coverage rainstorm warning, can reduce flood losses by 30–40%; and (ii) to reduce losses, it is more effective and cheaper to invest early in response measures than late actions. This dynamic agent-based modeling approach is an innovative attempt to quantify and model the role of human responses in flood loss assessments. The model is demonstrated being useful for analyzing household scale flood losses and responses and it has the potential to contribute to flood emergency planning resource allocation in pluvial flood incidents.  相似文献   
839.
When low-cost adsorbents are being used to remove contaminant ions (e.g. arsenate, vanadate, and molybdate) from wastewater, competitive adsorption/desorption are central processes determining their removal efficiency. Competitive adsorption of As, V, and Mo was investigated using equimolar oxyanion concentrations in single, binary, and tertiary combinations in adsorption isotherm and pH envelope studies while desorption of previously adsorbed oxyanions was examined in solutions containing single and binary oxyanion combinations. The low-cost adsorbent materials used were alum water treatment sludge (amorphous hydroxy-Al) and bauxite ore (crystalline Al oxides). Adsorption isotherm and pH envelope studies showed that Mo had only a small effect in decreasing adsorption of As and V but V and As had substantial and similar effects in reducing adsorption of the other. As had a greater effect than V in reducing adsorption of Mo and it was concluded that the affinity of oxyanions for the surfaces of water treatment sludge and bauxite followed the order As > V >> Mo. In 0.3 M NaCl electrolyte, desorption of previously adsorbed oxyanions amounted to 0.3–3.4% for V and As, and 11–20% for Mo. As had approximately four times greater effect than Mo in increasing desorption of V while V had about three times the effect of Mo in increasing desorption of As. Thus, the order of oxyanions in inducing desorption of the other oxyanions (i.e. As on V and As) was the same as that for adsorption selectivity: As > V >> Mo. Water treatment sludge was a more effective adsorbent than bauxite because it had a greater adsorption capacity for all three anions and, in addition, they were held more strongly so desorption in the background electrolyte was proportionately less. It was concluded that at similar molar concentrations, arsenate would tend to reduce adsorption of vanadate as well as displace vanadate already held on adsorbent surfaces while both anions will compete effectively with molybdate. The limiting factor for simultaneous removal of As, V, and Mo from multielement solutions by adsorption will therefore be the removal of Mo.  相似文献   
840.
Sustainability and sustainable development are prominent themes in international policy-making, corporate PR, news-media and academic scholarship. Its definitions are contested, however sustainability is associated with a three-pillar focus on economic development, environmental conservation and social justice, most recently espoused in the adoption of the UN Sustainable Development Goals in 2015. In spite of its common usage, there is little research about how sustainability is represented and refracted in public discourse in different national contexts. We examine British national press coverage of sustainability and sustainable development in 2015 in a cross-market sample of national newspapers. Our findings show that key international policy events and environmental and social justice frames are peripheral, while neoliberalism and neoliberal environmentalism vis-à-vis the promotion of technocratic solutions, corporate social responsibility and “sustainable” consumerism are the predominant frames through which the British news-media reports sustainability. This holds regardless of newspaper quality and ideological orientation.  相似文献   
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