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291.
Spatial systems approach to sustainable development: A conceptual framework   总被引:9,自引:0,他引:9  
Even though “sustainable development” seems to have emerged as the development paradigm of the 1990s, a great deal of vagueness still surrounds the meaning, definition, and theoretical underpinnings of the concept. There is also a general lack of emphasis on the spatial dimension of sustainable development when developing relevant conceptual or environmental accounting frameworks. In clarifying the concept, this article proposes a definition that explicitly incorporates the temporal as well as the spatial dimension of sustainability. It also develops a logically consistent conceptual framework for the analysis and evaluation of sustainable development, following a spatial systems approach. Five interconnected aspatial subsystems or subsets of a spatial system are identified and their respective operational dimensions discussed. A proposed composite index calleddegree of stainable development (DSD) and its five component indicators are also outlined. The difficulties involved in operationalizing the DSD measure and the conceptual framework are noted, and the various tasks that need to be undertaken in this regard are specified. It is concluded that future research utilizing the proposed conceptual framework should not only foster the development of appropriate methodologies for the comparative evaluation of sustainable development at global, national, or regional scales, but also offer insights to appropriate decision makers at various levels regarding available options and alternative actions for the healthy development of their respective societies.  相似文献   
292.
Advancements in the field of reintroduction biology are needed, but understanding of how to effectively conduct translocations, particularly with snakes, is lacking. We conducted a systematic review of snake translocation studies to identify potential tactics for reducing postrelease effects. We included studies on intentional, human-mediated, wild–wild, or captive–wild translocations to any location, regardless of motive or number of snakes translocated. Only studies that presented results for at least 1 of 4 outcomes (movement behavior, site fidelity, survival, or population establishment) were included. We systematically searched 4 databases for published studies and used 5 methods to search the gray literature. Our search and screening criteria yielded 121 data sources, representing 130 translocation cases. We quantified the association between 15 translocation tactics and short-term translocation outcomes by calculating odds ratios and used forest plots to display results. Snake translocations involved 47 species (from mainly 2 families), and most were motivated by research, were monitored for at least 6 months, occurred in North America, and took place from the 1990s onward. The odds of a positive snake translocation outcome were highest with release of captive reared or juvenile snakes, release of social groups together, delayed release, provision of environmental enrichment or social housing before release, or minimization of distance translocated. The odds of a positive outcome were lowest when snakes were released early in their active season. Our results do not demonstrate causation, but outcomes of snake translocation were associated with 8 tactics (4 of which were strongly correlated). In addition to targeted comparative studies, we recommend practitioners consider the possible influence of these tactics when planning snake translocations.  相似文献   
293.
This paper describes the construction and empirical evaluation of a new scale for measuring empowering leader behavior. Study One consisted of thorough interviews with external leaders and team members in three organizations. Behaviors elicited in the interviews were classified by researchers into eight categories of leader empowering behavior and the Empowering Leadership Questionnaire (ELQ) was constructed to measure each of these categories. In Study Two, the ELQ was administered to team members and leaders from two organizations. The results indicated that five‐factors (Coaching, Informing, Leading By Example, Showing Concern/Interacting with the Team, and Participative Decision‐Making) adequately describe the data. In Study Three, we cross‐validated the scale in a sample from five organizations and the factor analysis confirmed the five‐factor model. The ELQ dimensions were also compared with behaviors measured by two well‐established measures of leader behavior. The results indicated that the ELQ dimensions partially overlap with previously identified constructs, but that empowering leadership behavior can not be entirely accounted for by the earlier measures. Definitions and implications for the categories of empowering leader behaviors are offered. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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Stormwater runoff and associated pollutants from urban areas in the greater Chesapeake Bay Watershed (CBW) impair local streams and downstream ecosystems, despite urbanized land comprising only 7% of the CBW area. More recently, stormwater best management practices (BMPs) have been implemented in a low impact development (LID) manner to treat stormwater runoff closer to its source. This approach included the development of a novel BMP model to compare traditional and LID design, pioneering the use of comprehensively digitized storm sewer infrastructure and BMP design connectivity with spatial patterns in a geographic information system at the watershed scale. The goal was to compare total watershed pollutant removal efficiency in two study watersheds with differing spatial patterns of BMP design (traditional and LID), by quantifying the improved water quality benefit of LID BMP design. An estimate of uncertainty was included in the modeling framework by using ranges for BMP pollutant removal efficiencies that were based on the literature. Our model, using Monte Carlo analysis, predicted that the LID watershed removed approximately 78 kg more nitrogen, 3 kg more phosphorus, and 1,592 kg more sediment per square kilometer as compared with the traditional watershed on an annual basis. Our research provides planners a valuable model to prioritize watersheds for BMP design based on model results or in optimizing BMP selection.  相似文献   
297.
Hispanic residents suffer disproportionately from exposure to toxic pollution hazards, but little is known about why some Hispanic residents live in high-risk neighbourhoods while others are protected from similar risks. This study uses comparative interview-based methods to further understanding of Hispanic people’s residential decision-making and their associated exposures to hazardous air pollutants (HAPs) in the Miami Metropolitan Statistical Area (Florida), which is home to one of the most diverse Hispanic populations in the U.S. We use 22 in-depth interviews conducted with Hispanic householders living at high and low risk to HAPs, selected from a larger representative phone survey of 650 local residents. For Hispanic households at high risk, economic constraints, family ties, desiring a central location, a sense of community, and comfort in a shared culture contributed to their residences in high risk locations. In contrast, protective factors for Hispanic households living at low risk included the desire to live in an ethnically diverse setting, the ease of finding service work, and preferring environmental amenities and exclusivity. Findings demonstrate that there are considerable differences in factors shaping residential decision-making of low- and high-risk Hispanic residents, but that all were influenced by economic, socio-cultural, and environmental considerations to varying degrees.  相似文献   
298.
Raman spectroscopy was used to investigate sorption mechanisms of cephapirin (CHP), a veterinary antibiotic, onto quartz (SiO2) and feldspar (KAlSi3O8) at different pH. Sorption occurs by electrostatic attraction, monodentate and bidentate complexation. The zwitterion (CHPo) adsorbs to a quartz(+) surface by electrostatic attraction of the carboxylate anion group (-COO) at low pH, but adsorbs to a quartz(−) surface through electrostatic attraction of the pyridinium cation, and possibly COO bridge complexes, at higher pH. CHP bonds to quartz(−) surfaces by bidentate complexation between one oxygen of -COO and oxygen from carbonyl of an acetoxymethyl group. On a feldspar(+/−) surface, CHPo forms monodentate complexes between CO, and possible -COO bridges and/or electrostatic attachments to localized edge (hydr)oxy-Al surfaces. CHP adsorbs to feldspar(−) through monodentate CO complexation. Similar mechanisms may operate for other cephalosporins. Results demonstrate, for the first time, that Raman techniques can be effective for evaluating sorption mechanisms of antibiotics.  相似文献   
299.
Fragments of antifouling paint and environmental geosolids have been sampled from the island of Malta and analysed for total and bioaccessible metals. Total concentrations of Ba, Cd, Cu, Pb, Sn and Zn were two to three orders of magnitude higher in spent antifouling composites relative to respective values in background soils and road dusts. Paint fragments were visible in geosolids taken from the immediate vicinity of boat maintenance facilities and mass balance calculations, based on Ba as a paint tracer, suggested that the most contaminated soils, road dusts and boatyard dusts contained about 1%, 7% and 9%, respectively, of antifouling particles. Human bioaccessibilities of metals were evaluated in selected samples using a physiologically based extraction technique. Accessibilities of Cd, Cu, Pb and Zn in the most contaminated solids were sufficient to be cause for concern for individuals working in the boat repair industry and to the wider, local community.  相似文献   
300.
This paper examines the emerging role of digital tools in a collaborative planning process for British Columbia's Bowen Island. The goal of this research was to evaluate the effectiveness of a 'digital workshop', combining the interactive CommunityViz tool with the immersive lab facilities at the Collaborative for Advanced Landscape Planning (CALP). In support of the larger community planning process, two 3-h workshops were held at CALP's Landscape Immersion Lab. To facilitate collaborative exploration, the interactive landscape visualisation and real-time data analysis capabilities of CommunityViz were employed to illustrate the possible outcomes of residential density policies for Bowen Island's Snug Cove community. The community planning workshops were structured to provide the 14 semi-expert participants with the opportunity to explore and discuss the contentious residential density components of the draft Snug Cove Village Plan. The abilities to dynamically explore the visualisations of the planning proposals, and to see real-time changes in indicator metrics were considered particularly informative, and appeared to increase participants' understanding of the plan. Written and verbal responses indicated, however, that there was insufficient time to examine and interact with the information during the workshop, suggesting a need to examine in greater depth how and when these tools might best be employed in collaborative settings. Current and future research relating to this project is discussed.  相似文献   
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