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991.
If the search for values lies at the kernel of the philosophical ethical inquiry, then Lynch's monumental work, A Theory of Good City Form must be regarded as shaping the contours of an environmental design and planning ethic. The explicit connection between human values and settlement form in Lynch's theory reaches far in the realm of environmental design and planning, with ethical, legal, and procedural implications. Furthermore, the universal (performance) dimensions of the theory offer an accountability of the contingency of the particular (historical) conditions specific to place and society. A close scrutiny of the key theoretical dimensions suggests the possibility of bridging the procedure vs. substance, object vs. subject and means vs. ends chasms. Thus, certain ethical, legal, and procedural dilemmas encountered in competing theoretical perspectives are reconciled.  相似文献   
992.
Summary The purpose of this paper is to develop specific ecological design criteria for a sustainable Canadian society. Ecological design criteria complement socio-political ones which have also been developed by the Sustainable Society Project at the University of Waterloo. The criteria derive from an evaluation of the major areas of human activity and interaction with the natural environment in light of our knowledge of ecological systems and resource management. The criteria, like the Sustainable Society Project as a whole, are an attempt to suggest needed, feasible, medium to long-term changes in human activities to comply with the ecological and socio-political limits and constraints that must be recognized in order to achieve societal sustainability. The specific design criteria identified here are not the only ones possible, desirable, or necessary — a complete and certain list is inherently impossible. But the design criteria developed here are illustrative of the kinds of changes that are necessary to achieve sustainability.Dr D. Scott Slocombe is Assistant Professor in the Department of Geography, and Co-Director of the Cold Regions Research Centre, Wilfrid Laurier University. His principal research interests include ecosystem and regional planning, and management for sustainability.Caroline Van Bers was Project Manager for the Sustainable Society Project at the University of Waterloo and she received her MA from the School of Urban and Regional Planning at that University. She currently works in the State of the Environment Reporting Branch of Environment Canada.  相似文献   
993.
During reductive dechlorination of trichloroethene (TCE) by zero-valent iron, stable carbon isotopic values of residual TCE fractionate significantly and can be described by a Rayleigh model. This study investigated the effect of observed reaction rate, surface oxidation and iron type on isotopic fractionation of TCE during reductive dechlorination. Variation of observed reaction rate did not produce significant differences in isotopic fractionation in degradation experiments. However, a small influence on isotopic fractionation was observed for experiments using acid-cleaned electrolytic iron versus experiments using autoclaved electrolytic iron, acid-cleaned Peerless cast iron or autoclaved Peerless cast iron. A consistent isotopic enrichment factor of epsilon = -16.7/1000 was determined for all experiments using cast iron, and for the experiments with autoclaved electrolytic iron. Column experiments using 100% cast iron and a 28% cast iron/72% aquifer matrix mixture also resulted in an enrichment factor of -16.9/1000. The consistency in enrichment factors between batch and column systems suggests that isotopic trends observed in batch systems may be extrapolated to flowing systems such as field sites. The fact that significant isotopic fractionation was observed in all experiments implies that isotopic analysis can provide a direct qualitative indication of whether or not reductive dechlorination of TCE by Fe0 is occurring. This evidence may be useful in answering questions which arise at field sites, such as determining whether TCE observed down-gradient of an iron wall remediation scheme is the result of incomplete degradation within the wall, or of the dissolved TCE plume by passing the wall.  相似文献   
994.
Reproductive success and contaminant levels in 1986 and 1987 were compared between Barn Swallows nesting at selenium-contaminated Martin Lake, Texas, USA, and swallows nesting at a reference site. Nests were initiated about the same time or earlier at Martin Lake than at the reference site and clutch size was similar between the two locations. Nest success was significantly higher at Martin Lake than at the reference site and no embryo or chick deformities were documented. Selenium concentrations in 14 of 20 eggs from Martin Lake were above background (> 3 ppm, dry weight); two of 20 eggs contained > 5 ppm, a concentration associated with a 20% embryo mortality/deformity rate in some bird species. Selenium concentrations in the kidneys of adult swallows were higher at Martin Lake (mean = 14 ppm dry weight) than at the reference site (5.8 ppm). DDE, the only detected organochlorine compound, was in two of 10 eggs from Martin Lake; these concentrations were below those associated with chronic poisoning and reproductive problems. The maximum mercury concentration in livers of adult Barn Swallows (0.83 ppm, dry weight) was within the range for background levels (< 5 ppm).  相似文献   
995.
Three study areas of Kwanak campus (Seoul National University), Boeun (Choongbuk) and Gapyung (Kyonggi) were selected and classified according to their bedrock types in order to investigate soil–gas radon concentrations. The mean values of radon concentrations decreased in the order of Gapyung (40BqL–1) > Kwanak campus (30BqL–1) > Boeun (22BqL–1), and decreased in the order of granite gneiss > banded gneiss > granite > black slate–shale > mica schist > shale–limestone > phyllite schist according to bed rock types. Variation in radon emanation with water content in soils and with soil grain size was assessed by the modified Morse (1976) 3min method. Soil–gas radon concentrations increased with increasing water content in the range of less than about 6–16wt.%, but decreased above 6–16wt.%. Radon concentrations also increased with decreasing soil grain size. Radioactivity analysis of radionuclides of 238U series in some soil samples indicated their possible radioactive disequilibrium between 226Ra and 238U due to the differing geochemical behaviour of intermediate radionuclides. Thus, a radioactive isotope geochemical approach should be necessary for soil–gas radon study.  相似文献   
996.
This paper presents a new concept to include uncertainty management in energy and environmental planning models developed in algebraic modeling languages. SETSTOCH is a tool for linking algebraic modeling languages with specialized stochastic programming solvers. Its main role is to retrieve from the modeling language a dynamically ordered core model (baseline scenario) that is sent automatically to the stochastic solver. The case presented herein concerns such a study realized with the IEAMARKAL model used by many research teams around the world.  相似文献   
997.
Understanding the ecology, condition, and changes of coastal areas requires data from many sources. Broad-scale and long-term ecological questions, such as global climate change, biodiversity, and cumulative impacts of human activities, must be addressed with databases that integrate data from several different research and monitoring programs. Various barriers, including widely differing data formats, codes, directories, systems, and metadata used by individual programs, make such integration troublesome. Coastal data partnerships, by helping overcome technical, social, and organizational barriers, can lead to a better understanding of environmental issues, and may enable better management decisions. Characteristics of successful data partnerships include a common need for shared data, strong collaborative leadership, committed partners willing to invest in the partnership, and clear agreements on data standards and data policy. Emerging data and metadata standards that become widely accepted are crucial. New information technology is making it easier to exchange and integrate data. Data partnerships allow us to create broader databases than would be possible for any one organization to create by itself.  相似文献   
998.
The aim of this study is to identify management practices that effectively reduce greenhouse gas (GHG) emissions with regard to the green supply chain adopted by mobile phone producers. Six cases were surveyed (Apple, Samsung, LG, Huawei, Nokia, and ZTE). The main source of data was sustainability reports, which were retrieved from the Global Reporting Initiative database. A special data analysis technique called rank analysis was adopted. The results revealed that the effective practices to reduce GHG 1 emissions were related to production process and business travel; those that were effective for reducing GHG 2 emissions were related to facilities accreditation and energy saving; and those effective in reducing GHG 3 emissions were related to logistics and customer practices. No effective actions related to the management of relationships with suppliers were identified by this study. Indicative models for the relationship between actions and GHG emissions were developed, as was a value‐stream map. The previous studies reporting the effective practices in other industries reported results for reducing GHG 1 or GHG 3, or overall GHG emissions, without discriminating among the actions taken to reduce such emissions, although some limited actions were reported. This study describes the effective practices along the whole supply chain—both upstream and downstream—and it also lists the actions related to addressing all the emissions, whether GHG 1, 2, or 3.  相似文献   
999.
National Water Model (NWM) simulates the hydrologic cycle and produces streamflow forecasts for 2.7 million reaches in the National Hydrography Dataset for continental United States (U.S.). NWM uses Muskingum–Cunge channel routing, which is based on the continuity equation. However, the momentum equation also needs to be considered to obtain more accurate estimates of streamflow and stage in rivers, especially for applications such as flood‐inundation mapping. Here, we used a steady‐state backwater version of Simulation Program for River NeTworks (SPRNT) model. We evaluated SPRNT’s and NWM’s abilities to predict inundated area for the record flood of Hurricane Matthew in October 2016. The Neuse River experienced record‐breaking floods and was well‐documented by U.S. Geological Survey. Streamflow simulations from NWM retrospective analysis were used as input for the SPRNT simulation. Retrospective NWM discharge predictions were converted to stage. The stages (from both SPRNT and NWM) were utilized to produce flood‐inundation maps using the Height Above Nearest Drainage method which uses the local relative heights to find out the local draining potentials and provide spatial representation of inundated area. The inundated‐area accuracies for NWM and SPRNT (based on comparison to a remotely sensed dataset) were 65.1% and 67.6%, respectively. These results show using steady‐state SPRNT results in a modest improvement of inundation‐forecast accuracy compared to NWM.  相似文献   
1000.
A public mobilization approach known as nikinake drives implementation and technology upscaling in Ethiopia's agricultural extension. This study investigates and describes the processes and effectiveness of nikinake as an extension method used for natural resource management (NRM). The paper draws on empirical field research conducted in Oromia and the southern region of Ethiopia by looking at nikinake in the context of a watershed management campaign in 2015 and 2016. Nikinake is used as an approach to mobilize the public and to promote the skills of farmers and development actors. In principle, the implementation of NRM is voluntary; however, it is largely planned top‐down and enforced through state actors and informal institutions. This study suggests effective integration of social mobilization with reliable extension and a paradigm shift in emphasis from spatial coverage to an effective outcome. Additionally, sustainability and scalability of NRM interventions could be ameliorated by improving experts’ technical skills, raising farmers’ awareness, improving an incentive system, building trust, and better integrating past watershed management and future planning activities. We reflect on the significance of the nikinake experience in Ethiopia for a broader theory of extension‐as‐mobilization for rural development. From the Ethiopian case, a more general recommendation emerges for extension‐as‐mobilization schemes. For long‐term development, it is worthwhile to consider the fit between yearly campaigns as ad hoc project organizations and the existing pattern of actors and institutions responsible for rural development.  相似文献   
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