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701.
Global human progress occurs in a complex web of interactions between society, technology and the environment as driven by governance and infrastructure management capacity among nations. In our globalizing world, this complex web of interactions over the last 200 years has resulted in the chronic widening of economic and political gaps between the haves and the have-nots with consequential global cultural and ecosystem challenges. At the bottom of these challenges is the issue of resource limitations on our finite planet with increasing population. The problem is further compounded by pleasure-driven and poverty-driven ecological depletion and pollution by the haves and the have-nots respectively. These challenges are explored in this paper as global sustainable development (SD) quantitatively; in order to assess the gaps that need to be bridged.Although there has been significant rhetoric on SD with very many qualitative definitions offered, very few quantitative definitions of SD exist. The few that do exist tend to measure SD in terms of social, energy, economic and environmental dimensions. In our research, we used several human survival, development, and progress variables to create an aggregate SD parameter that describes the capacity of nations in three dimensions: social sustainability, environmental sustainability and technological sustainability. Using our proposed quantitative definition of SD and data from relatively reputable secondary sources, 132 nations were ranked and compared.Our comparisons indicate a global hierarchy of needs among nations similar to Maslow's at the individual level. As in Maslow's hierarchy of needs, nations that are struggling to survive are less concerned with environmental sustainability than advanced and stable nations. Nations such as the United States, Canada, Finland, Norway and others have higher SD capacity, and thus, are higher on their hierarchy of needs than nations such as Nigeria, Vietnam, Mexico and other developing nations. To bridge such gaps, we suggest that global public policy for local to global governance and infrastructure management may be necessary. Such global public policy requires holistic development strategies in contrast to the very simplistic north–south, developed–developing nations dichotomies.  相似文献   
702.
Conventional methods for management of data‐rich fisheries maintain sustainable populations by assuring that lifetime reproduction is adequate for individuals to replace themselves and accounting for density‐dependent recruitment. Fishing is not allowed to reduce relative lifetime reproduction, the fraction of current egg production relative to unfished egg production (FLEP), below a sustainable level. Because most shark fisheries are data poor, other representations of persistence status have been used, including linear demographic models, which incorporate life‐history characteristics in age‐structured models with no density dependence. We tested how well measures of sustainability from 3 linear demographic methods (rebound potential, stochastic growth rate, and potential population increase) reflect actual population persistence by comparing values of these measures with FLEP for 26 shark species. We also calculated the value of fishing mortality (F) that would allow all 26 species to maintain an accepted precautionary threshold for sharks of FLEP = 60%, expressing F as a fraction of natural mortality (M). Values of stochastic growth rate and potential population growth did not covary in rank order with FLEP (p = 0.057 and p = 0.077, respectively) and neither was significantly correlated with FLEP. Ordinal ranking of rebound potential positively covaried with FLEP (p = 0.00013), but the relative rankings of some species were substantially out of order. Adopting a sustainable limit of F = 0.16M would maintain all 26 species above the precautionary minimum value of FLEP (60%). We concluded that shark‐fishery and conservation policies should rely on calculation of replacement (i.e., FLEP), and that sharks should be fished at a precautionary level that would protect all stocks (i.e., F< 0.16M). Comparación entre Modelos Demográficos Lineales y la Fracción de Producción de Huevos a lo Largo de la Vida para Estudiar la Sustentabilidad en Tiburones Resumen  相似文献   
703.
经实地考察、典型调查和分析研究 ,构建了以可持续发展度为目标的岳西县生态示范区评价指标体系 ,由 4个层次 18项指标组成。采用加权求和计量模型计算了岳西县规划基准年、近期和远景目标年的可持续发展度值。  相似文献   
704.
This paper utilizes an inclusive community based sustainability framework with a focus on a resort destination in providing a potential model for more inclusive long-range destination planning and implementation. Four diverse, but interrelated areas of sustainable tourism were specified in this framework for a more comprehensive process including ecological, cultural, economic and socio-community sustainability. In addition a strategic community driven structure, which provides direction, information and practices, serves the purpose of integrating and implementing the framework. The unique tourism destination, Noosa in Australia is used as an example of embracing sustainable tourism as a community and as part of a larger focus on the four key components of sustainability. By viewing sustainable community attributes as assets, all of which are important to manage, enhance and/or conserve, it is expected that the resort community will continue to attract visitors to feel connected and committed to experiencing its lifestyle, sense-of-community and natural features while also contributing to community sustainable stewardship and a strong tourism economy. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. Dr. Richins is Chair of the Graduate Program within the School of Travel Industry Management at University of Hawaii. He holds a Ph.D. from James Cook University in Australia and a B.S. and M.S. from University of Oregon. Previously he held leadership positions for over 15 years in Australian and New Zealand including Waikato University, University of Newcastle and University of the Sunshine Coast. He was also Chair of the Resort Management program at Sierra Nevada College in Nevada.  相似文献   
705.
Urban sustainability literature calls for new governance relations to support green urban agendas. Privileging non-hierarchical relations, this literature fails to address the means by which organisations create these capacities. The author interviewed public, private and community environmental leaders in metropolitan Chicago regarding their disposition toward creating boundary spanning organisations (BSOs) in addressing the City's Environmental Action Agenda. Their responses reflect engaged efforts to enhance cross-boundary sharing of information, resources, and power. However, they also reflect the decisive role of central authority in initiating this process. These findings suggest the complexity of urban governance in transitions toward sustainability and the opportunities they provide to explore the implications of on-the-ground practice.  相似文献   
706.
Clark, Gregory M., 2010. Changes in Patterns of Streamflow From Unregulated Watersheds in Idaho, Western Wyoming, and Northern Nevada. Journal of the American Water Resources Association (JAWRA) 46(3):486-497. DOI: 10.1111/j.1752-1688.2009.00416.x Abstract: Recent studies have identified a pattern of earlier spring runoff across much of North America. Earlier spring runoff potentially poses numerous problems, including increased risk of flooding and reduced summer water supply for irrigation, power generation, and migratory fish passage. To identify changing runoff patterns in Idaho streams, streamflow records were analyzed for 26 U.S. Geological Survey gaging stations in Idaho, western Wyoming, and northern Nevada, each with a minimum of 41 years of record. The 26 stations are located on 23 unregulated and relatively pristine streams that drain areas ranging from 28 to >35,000 km2. Four runoff parameters were trend tested at each station for both the period of historical record and from 1967 through 2007. Parameters tested were annual mean streamflow, annual minimum daily streamflow, and the dates of the 25th and 50th percentiles of the annual total streamflow. Results of a nonparametric Mann-Kendall trend test revealed a trend toward lower annual mean and annual minimum streamflows at a majority of the stations, as well as a trend toward earlier snowmelt runoff. Significant downward trends over the period of historical record were most prevalent for the annual minimum streamflow (12 stations) and the 50th percentile of streamflow (11 stations). At most stations, trends were more pronounced during the period from 1967 through 2007. A regional Kendall test for water years 1967 through 2007 revealed significant regional trends in the percent change in the annual mean and annual minimum streamflows (0.67% less per year and 0.62% less per year, respectively), the 25th percentile of streamflow (12.3 days earlier), and the 50th percentile of streamflow (11.5 days earlier).  相似文献   
707.
Since United Nations adopted the global Sustainable Development Goals (SDGs) for the next 15 years (2016–2030), sustainable development will further become a core concept and main principle to guide global and national economic and social development. According to this background, strengthening the integrative research on the theories and methodologies of sustainable development has been a strategically important mission. This article provided an analytic framework for sustainability science, named the object-subject-process (OSP) framework for examining the key issues encountered during the theoretical research and policy analysis. This study emphasized that, on the object dimension, sustainable development means to seek for economic and social development within biophysical limits of the earth and the relationship of environment, society, and economy should be containing and complementary rather than parallel and substitute; on the process dimension, sustainable development should adopt both the responsive and proactive strategies for the whole process management which employing pressure-state-response (PRS) model rather than dealing with one part of them; on the subject dimension, sustainable development research should involve the key stakeholders who are kind of collaborate governance rather than separate each other. From the perspective of sustainability science, green economy was utilized as a case study to explore the issues of object, process and subject and also the significance of green economy was discussed in this study.  相似文献   
708.
农业规模经营是实现农业现代化的重要路径。为了探讨丘陵山区农业规模化发展对于水土流失的影响机理。通过文献综述法梳理相关研究,分析现有研究存在的不足,并提出研究展望。综观前人的研究可以得知:(1)农业规模经营的效益、政策与推动机制等状况;(2)丘陵山区水土流失的影响因素乃为自然因素与人为因素交互作用的结果,以及农业活动对水土流失的影响;(3)水土流失的调查、监测与影响因素的评估方法及仿真模拟。最后,提出5点研究展望:(1)构建丘陵山区水土流失驱动力模型;(2)建立丘陵山区农业规模化对水土流失的影响评估指标体系;(3)甄别影响程度及其时空差异;(4)丘陵山区农业规模化的水土流失效应模拟反演;(5)提出丘陵山区水土资源可持续利用的农业规模化政策建议。以期对我国丘陵山区发展适度农业规模化与可持续发展研究提供科学参考。  相似文献   
709.
Water availability risk is a local issue best understood with watershed‐scale quantification of both withdrawal and consumptive demands in the context of available supply. Collectively, all water use sectors must identify, understand, and respond to this risk. A highly visual and computationally robust decision support tool, Water Prism, quantitatively explores mitigation responses to water risk on both a facility‐level and basin‐aggregated basis. Water Prism examines a basin water balance for a 40‐ to 60‐year planning horizon, distinguishes among water use sectors, and accounts for ecosystem water needs. The 2012 Texas State Water Plan was used to apply Water Prism to the Big Cypress‐Sulphur Basin (Texas). The case study showed Water Prism to be an accurate and convenient tool to provide fine‐scale understanding of water use in the context of available supply, evaluate multi‐sector combinations of conservation strategies, and quantify the effects of future demands and water availability. Analyses demonstrated water availability risks for rivers and reservoirs can vary within a basin and must be calculated independently, simulation of water balance conditions can help illuminate potential impacts of increasing demands, and scenario simulations can be used to evaluate relative conservation efficacy of different water resource management strategies for each sector. Based on case study findings, Water Prism can serve as a useful assessment tool for regional water planners.  相似文献   
710.
Interbasin transfers (IBTs) are man‐made transfers of water that cross basin boundaries. These transfers are used to distribute water resources according to supply and demand. The objectives of this work were to quantify the number of IBTs that exist in the United States (U.S.) and to examine the distribution of IBTs and potential causes associated with any observed clustering of IBTs. Defining “basin” was important to enable determination of which transfers qualify as “interbasin.” A variety of definitions are employed by states, with no federal definition. The most recent national studies of IBTs were conducted by the U.S. Geological Survey (USGS) in 1985 and 1986 using USGS Hydrologic Unit Code (HUC) definitions of basins. To build a 2016 inventory of IBTs in the U.S., and to identify where they most commonly occur, the USGS National Hydrography Database (NHD) was utilized in conjunction with the Watershed Boundary Dataset (WBD). Transfers across HUC6 basin boundaries were considered interbasin. Geographical information analysis with the NHD and WBD databases revealed that there are a total of 2,161 man‐made waterways crossing HUC6 basin boundaries in the U.S. IBTs are somewhat concentrated: Florida, Texas, and North Carolina account for over 50% of the total identified IBTs. For some states, identified IBTs are locally clustered. Analysis of these clusters suggests a variety of reasons that IBTs have been built, including population, drainage, and agricultural factors.  相似文献   
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