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351.
Esther S. Parish Keith L. Kline Virginia H. Dale Rebecca A. Efroymson Allen C. McBride Timothy L. Johnson Michael R. Hilliard Jeffrey M. Bielicki 《Environmental management》2013,51(2):307-338
Understanding the environmental effects of alternative fuel production is critical to characterizing the sustainability of energy resources to inform policy and regulatory decisions. The magnitudes of these environmental effects vary according to the intensity and scale of fuel production along each step of the supply chain. We compare the spatial extent and temporal duration of ethanol and gasoline production processes and environmental effects based on a literature review and then synthesize the scale differences on space–time diagrams. Comprehensive assessment of any fuel-production system is a moving target, and our analysis shows that decisions regarding the selection of spatial and temporal boundaries of analysis have tremendous influences on the comparisons. Effects that strongly differentiate gasoline and ethanol-supply chains in terms of scale are associated with when and where energy resources are formed and how they are extracted. Although both gasoline and ethanol production may result in negative environmental effects, this study indicates that ethanol production traced through a supply chain may impact less area and result in more easily reversed effects of a shorter duration than gasoline production. 相似文献
352.
Adriana X. Sanchez Liisa M. Lehtiranta Keith D. Hampson 《Journal of Environmental Planning and Management》2015,58(11):1923-1943
The type of contract model may have a significant influence on achieving project objectives, including environmental and climate change goals. This research investigates non-standard contract models impacting greenhouse gas emissions (GHG) in transport infrastructure construction in Australia. The research is based on the analysis of two case studies: an Early Contractor Involvement (ECI) contract and a Design and Construct (D&C) contract with GHG reduction requirements embedded in the contractor selection. Main findings support the use of ECIs for better integrating decisions made during the planning phase with the construction activities, and improve environmental outcomes while achieving financial and time savings. 相似文献
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355.
While ecologists have used food‐web models to understand how ecosystems function, the potential role of integrated food‐web and population‐based models in environmental monitoring and decision making has been ignored. Sound ecological principles should be integrated with state‐of‐the‐art monitoring and management practices. This article presents the ways in which population‐based models can answer basic ecological questions necessary for decision making about remediation and restoration, and for monitoring to ensure long‐term stewardship. Discussed are the uses of food‐web and population‐based models for understanding the movement of chemicals through different trophic levels. Three examples, including global warming, tributyltin, and monomethylmercury scenarios, are presented to illustrate how such models are useful. The responses of the component parts varies, depending on parameters such as birth, death, and respiration, as well as feeding rates, predator‐prey rates, and uptake and elimination rates. There are several different models available for decision making, with different levels of complexity, based on the specific hypothesis or question being asked and the amount of current information available. Therefore, it is recommended to use deterministic‐based, population‐based food‐web models for ecological risk assessment. © 2001 John Wiley & Sons, Inc. 相似文献
356.
Faith A. Fitzpatrick Mitchell A. Harris Terri L. Arnold Kevin D. Richards 《Journal of the American Water Resources Association》2004,40(2):461-475
ABSTRACT: Biotic indices and sediment trace element concentrations for 43 streams in northeastern Illinois (Chicago area) from the 1980s and 1990s were examined along an agricultural to urban land cover gradient to explore the relations among biotic integrity, sediment chemistry, and urbanization. The Illinois fish Alternative Index of Biotic Integrity (AIBI) ranged from poor to excellent in agricultural/rural streams, but streams with more than 10 percent watershed urban land (about 500 people/mi2) had fair or poor index scores. A macroinvertebrate index (MBI) showed similar trends. A qualitative habitat index (PIBI) did not correlate to either urban indicator. The AIBI and MBI correlated with urban associated sediment trace element concentrations. Elevated copper concentrations in sediment occurred in streams with greater than 40 percent watershed urban land. The number of intolerant fish species and modified index of biotic integrity scores increased in some rural, urbanizing, and urban streams from the 1980s to 1990s, with the largest increases occurring in rural streams with loamy/sandy surficial deposits. However, smaller increases also occurred in urban streams with clayey surficial deposits and over 50 percent watershed urban land. These data illustrate the potentially complex spatial and temporal relations among biotic integrity, sediment chemistry, watershed urban land, population density, and regional and local geologic setting. 相似文献
357.
Keith Willett David M. Mitchell H. L. Goodwin Baxter Vieux Jennie S. Popp 《Journal of Environmental Planning and Management》2006,49(2):181-207
The Illinois River Basin in eastern Oklahoma and northwest Arkansas is an example of a region where significant growth in poultry production has been accompanied by water quality problems. The primary concern in the basin is the problem of phosphorus in runoff that is associated with application of litter to crops. Existing data suggest that there has been a continuing decline in the quality of water in the Illinois River, and discussions have focused on developing and implementing a phosphorus standard. The specific objectives of this study are to estimate the reduction in poultry production necessary to achieve the reduction in phosphorus runoff under a set of phosphorus constraints, including soil test phosphorus, and to estimate the opportunity costs of reducing poultry production in the basin under each phosphorus constraint on the economic activity in the watershed. A mathematical programming model that incorporates poultry production and cropping decisions is developed. The parameters for the model are identified and then it is solved to provide a base solution. Model solutions are then developed for the different policy target levels of phosphorus. The model structure is modified to account for the presence of soil test phosphorus levels and the corresponding limits on soil test phosphorus throughout the basin. This formulation includes current soil test phosphorus throughout the basin. All of the applications assume that the only disposal option for poultry litter is land application within the basin. An economic impact assessment of the effects of phosphorus limitations in the basin is also conducted for Arkansas counties only, Oklahoma counties only, and all five affected counties combined. 相似文献
358.
Keith W. Hipel 《Journal of the American Water Resources Association》1988,24(3):487-492
ABSTRACT: The interesting developments in non-parainetric testing and estimation methods presented in the upcoming sequence of nine papers are evaluated, compared, and put into proper perspective. Because a deterioration in water quality constitutes a direct threat to human health, it is of utmost importance to have flexible non-parametric methods available for detecting and describing trends in water quality time series. A distinct advantage of nonparametric tests is that they are usually very effective when applied to “messy” environmental data which may, for example, contain many missing observations and not be normally distributed. By applying their enhanced approaches for nonparametric methods to water quality time series, as well as employing well designed simulation experiments, the authors of the papers clearly demonstrate the efficacy of utilizing nonparametric tests in environmental impact assessment. 相似文献
359.
This article reviews planning issues relating to “high‐tech” industry in Britain, and uses a case study of a manufacturer of micro‐computers in Oxford, England as a focus for a discussion. It concludes that town planning categories are not, in themselves, a constraint on high technology firms, and suggests that the provision of sites and premises by local authorities is a useful and undervalued task. 相似文献
360.
Injury prevention in natural disasters. A theoretical framework 总被引:1,自引:0,他引:1
A theoretical framework for conceptualizing injury patterns in natural disasters is described. In this conceptual framework, natural disasters are divided chronologically into predisaster, disaster and postdisaster phases. Within each phase, four factors (human, engineering/technological, physical environmental and socioeconomic) are identified that play an important role in the causation of injury. By combining these phases and factors into a three by four matrix, one may begin to identify points in the natural history or evolution of a disaster that may be amenable to therapeutic or preventive intervention. The application of this proposed three-phase matrix model to a disaster will permit researchers to reduce a large, complex problem into more manageable, conceptually simpler parts. It may also be of value to disaster planners by suggesting preventive and mitigation measures, as well as aiding in the setting of priorities so that scarce resources can be allocated to achieve maximum reduction of injuries. 相似文献