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121.
A diversion system has been designed to carry the flow from East Fork of Coal Creek around the area proposed for mining at Thunder Basin Coal Company's (TBCC) Coal Creek mine in Campbell County, Wyoming. This paper describes the field and analysis procedures necessary to prepare the diversion design and impact evaluation, and the innovative concepts developed for the diversion system design to minimize impacts on downstream channel stability. Under the proposed diversion system design, water from the East Basin of Coal Creek will be diverted at two locations. At one location, flow will be impounded by a small dam and decanted by a pump through a pipeline into East Fork at the location of the second diversion. At this location, a training dike will be placed across the stream channel to divert flows into a diversion channel. Gravity flow along the diversion channel will deliver water to a playa area which will be converted into a detention basin by placing a small dam across its southern end. Flows up to the magnitude of the 24-hour 2-year peak flow will be passed directly through the detention basin into Middle Fork with negligible attenuation of flow rates. For less frequent events, water will be stored in the detention basin in order to prevent velocities in Lower Middle Fork from exceeding the maximum permissible velocity above which scouring may occur. Evaporation and seepage losses from the diversion system were estimated to be small and should be more than offset by the addition of water from the playa drainage basin into the Coal Creek drainage. Velocities predicted for the Lower Middle Fork after-the diversion is constructed are expected to be low enough that significant erosion of the channel is not expected to occur.  相似文献   
122.
Monitoring concentrations of organic pollutants in water is essential to predict effects and to initiate preventive steps. Results from the analysis of water samples provide snapshots of a situation, whereas monitoring using semipermeable membrane devices (SPMDs) provides a time-integrated picture of the concentration of pollutants in water. In this investigation, SPMDs, caged mussels and water samples were used to monitor the levels of organotin compounds in the inner Oslofjord, Norway, over a period of 12 weeks. The work-up procedure for the analysis of organotins was optimised, focusing on the clean-up procedure using gel permeation chromatography (GPC). By using several GPC columns, as much as 1 g of triolein could be employed. This reduces the background emission noise on the baseline, leading to an improvement in the detection limits. The main uptake of tributyltin (TBT) in mussels and SPMDs levelled off after 14 days. A longer uptake period was indicated for SPMDs at stations with a high water concentration of TBT (5-10 ng Sn L(-1)) compared with those with a low water concentration of TBT (approximately 1 ng Sn L(-1)). A concentration gradient was observed for water, SPMDs and mussels from the innermost station close to Oslo harbour to the station further out in the fjord, indicating that the three analysed matrices give approximately the same pollution gradient. The bioconcentration factor (BCF) for TBT in mussels was in the range 12-14 000 (wet weight) and, for SPMDs, 10-12 000 (fat). A good correlation with the TBT water concentrations was achieved within a period of 14-30 days of exposure for mussels and after 2-3 months for SPMDs. A good correlation was also found between the TBT concentration in SPMDs and mussels at the end of the experiment. SPMDs can therefore be used to predict concentrations of TBT in both water and mussels.  相似文献   
123.
Two approaches to formulating the reserve site selection problem when species occurrence data is probabilistic were solved for terrestrial vertebrates in a small set of potential reserve sites in Oregon. The expected coverage approach, which maximizes the sum of the occurrence probabilities, yielded solutions that covered more species on average in Monte Carlo simulations than the threshold approach, which maximizes the number of species for which the occurrence probability exceeds some threshold.  相似文献   
124.
In the context of integrated assessment, the authors address the issue of uncertainty and subjectivity in modelling. In relating bias to different perspectives, the authors introduce the methodology of multiple model routes, which are reflections of different perceptions of reality and various policy preferences. As heuristic they use three perspectives, which are distinguished in cultural theory. The article describes case-studies on the population and health controversy in order to illustrate the possibilities of their approach. The article concludes with discussing the lessons learned by applying this methodology.  相似文献   
125.
An increasing number of studies indicate that marine mammals and some seabirds are exposed to organotins. However, results from northern and Arctic areas are few. Here results from analysis of tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPhT), diphenyltin (DPhT) and monophenyltin (MPhT) in harbour porpoise (Phocoena phocoena), common seal (Phoca vitulina), ringed seal (Phoca hispida) and glaucous gull (Larus hyperboreus) from Norwegian territory are presented. Relatively high concentrations of DBT, TBT and MBT were observed in muscle, kidney and liver from harbour porpoises caught in northern Norway in 1988, just before restrictions on the use of tributyltin (TBT)(mainly on small boats) were introduced in several European countries. The concentrations in harbour porpoise muscle tissue were reduced significantly 11 years later, possibly as a result of the introduced restrictions. Considerably lower concentrations of butyltins were observed in the seals compared to porpoises. The lowest levels of organotins were found in ringed seals from Spitsbergen, where only traces of dibutyltin (DBT) and monobutyltin (MBT) were observed. Traces of DBT and MBT were also found in some individual glaucous gulls from Bear Island. The sum of the degradation products MBT and DBT in liver samples from all analysed species were generally higher than TBT itself. Triphenyltin (TPhT) was observed in all porpoise samples and in livers of common seals. Also the sum of the degradation products MPhT and DPhT in liver samples from porpoise and common seals were higher than TPhT. No traces of phenyltins were found in ringed seals from Spitsbergen or in glaucous gulls from Bear Island. The limited data available indicate low to moderate exposure to organotins in northern areas (Spitsbergen and Bear Island). Marine mammals are however more exposed further south along the Norwegian Coast.  相似文献   
126.
Pesticide use is a common practice to control pests and diseases in vegetable cultivation, but often at the expense of the environment and human health. This article studies pesticide-buying and use practices among smallholder vegetable farmers in the Central Rift Valley of Ethiopia, using a practice perspective. Through in-depth interviews and observations, data were collected from a sample of farmers, suppliers and key governmental actors. The results reveal that farmers apply pesticides in violation of the recommendations: they use unsafe storage facilities, ignore risks and safety instructions, do not use protective devices when applying pesticides, and dispose containers unsafely. By applying a social practice approach, we show that these pesticide-handling practices are steered by the combination of the system of provision, the farmers’ lifestyle and the everyday context in which pesticides are being bought and used. Bringing in new actors such as environmental authorities, suppliers, NGOs and private actors, as well as social and technological innovations, may contribute to changes in the actual performance of these pesticides buying and using practices. This article argues that a practice approach represents a promising perspective to analyse pesticide handling and use and to systematically identify ways to change these.  相似文献   
127.
It is frequently argued that, at the parcel level, 1 stakeholders are capable of and well supported in managing their land‐related risks. Yet, evidence from the contemporary Australian context suggests otherwise: numerous large‐scale disaster events have revealed that citizens are ill‐prepared to respond and recover adequately. This paper begins with the premise that information, specifically land information, could better support parcel‐level risk preparation, mitigation, response, and recovery. State land administration organisations in Australia primarily maintain this information and make it accessible. Land information is used regularly across all levels of government to support risk management activities; however, such application has not always occurred at the parcel and citizen level. Via a case study approach, this paper initially explores the land information available in Australia to stakeholders interested in parcel‐level detail, and then goes on to propose how the utilisation of parcel‐level land information could serve to enhance risk management practices.  相似文献   
128.
The present study sought to objectively demonstrate how a researcher can, in a structured way, select relevant articles about alternative heterogeneous catalysts in photocatalytic processes. Therefore, the ProKnow-C (Knowledge Development Process – Constructivist) method was used to systematize the results found, with the application bibliometric and systematic analysis techniques for the evaluation of the results. The search string adopted as criteria was: solar photocatalysis AND heterogeneous catalysts OR alternative catalysts AND effluents. The databases were Web of Science, Science Direct and Scopus. The final bibliographic portfolio obtained for the research theme was made up of 19 articles. It was possible to verify advances in the number of publications on the theme over the evaluated period, with the Journal of Photochemistry and Photobiology A: Chemistry standing out in the final portfolio. Evaluating each article in the portfolio individually, it was possible to verify that most studies use combinations of catalysts already reported to create an alternative material to those already investigated in the literature. Those that use waste as catalysts chose to source this material from treatment plants and the steel industry. Around 58% of the papers used hydrogen peroxide in their processes, while 42% chose not to use it. Finally, approximately 63% of the papers in the portfolio used synthetic effluent in their processes, while the rest (37% of the research) chose to use real effluent. The results obtained in this research by applying the method can contribute to studies related to heterogeneous photocatalysis by alternative means over the years.  相似文献   
129.
Journal of Material Cycles and Waste Management - Distillation by-products of two Ocimum sp. were recycled through extraction of phenolic compounds and development of functional material like...  相似文献   
130.
The Ports of Los Angeles and Long Beach are the entry point for almost half of all cargo containers entering the United States. The use of diesel trucks to move Port-related goods has raised significant public health concerns associated with black carbon and other air pollutants. It is difficult to reliably estimate people's exposure to vehicle-related pollutants due to the narrow impact zone of traffic, usually within 200–300 m downwind of major roadways. Previous studies suffer from the lack of traffic count data on surface streets and the lack of neighborhood-level population data. We examined seasonal and annual average exposures of particulate matter less than 2.5 μm (PM2.5) and elemental carbon (EC) at a neighborhood scale for communities heavily impacted by diesel trucks near these ports. We assembled a traffic-activity database that distinguishes gasoline and diesel vehicles on both freeways and surface streets, by consolidating information from several sources, including our own field measurements. The CALINE4 model was used to estimate residential exposure of the study population to PM2.5 and EC. Parcel property data were used to allocate Census block group (BG) population to increase spatial resolution. The annual average PM2.5 and EC exposure due to local traffic was 3.8 and 0.4 μg m?3, respectively. On average, surface streets contributed a little more than freeways (55% vs. 45% for EC and 57% and 43% for PM2.5). Light-duty vehicles contributed significantly more than heavy-duty trucks for PM2.5 (61% vs. 39%), but slightly less than heavy-duty trucks for EC (49% vs. 51%). Community mean population exposure was similar using parcel, census block, and BG population data, but extreme values and standard deviations varied significantly at different spatial resolutions. The intake fraction for the study population was in the range of 1.0–2.2 × 10?5 by vehicle type, roadway type, and season.  相似文献   
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