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121.
Sustainable development, as a multi-dimensional concept, is difficult to measure. Some efforts using indicators and indices have appeared in recent years, but most were developed on a national scale. Use of sustainability indicators has proven valuable for attaining better management of the environment by minimizing information gaps and maximizing community capabilities in terms of economic, social, environmental, and institutional sustainability dimensions. However, at least in the case of developing countries, the potential exists that national sustainability measures, based on national level indicators, may mask problems in sub-national zones with highly unsustainable conditions. This paper proposes a methodology to evaluate sustainable development at a local level, the use of which could be helpful in comparing different regions within a country or even among different countries. National sustainability indicators should result from a combination (whether additive or proportional) of regional sustainability indicators, as developed in this paper.  相似文献   
122.
In this paper, we review three broad classes of indicators of sustainable development. These are economic, ecological and sociopolitical indicators. We then report the results of a pilot study which measured five different indicators for Scotland: an approximate environmentally-adjusted Net National Product; the Pearce-Atkinson Measure; Net Primary Production; Appropriated Carrying Capacity; and the Index of Sustainable Economic Welfare. We find that not all indicators point in the same direction, but a majority suggest that Scotland is at best only marginally sustainable. Data limitations, however, suggest a degree of caution in the interpretation of these results.  相似文献   
123.
SUMMARY

Sustainable indicators have become popular tools by which policymakers can assess progress towards a more sustainable agriculture. Varying approaches to defining sustainability lead to disagreement about the value of indicators and yet some form of measurement is required so that society can judge the effects of policy. Environmental and social problems and their causes span national boundaries. An international framework for assessing agricultural activities, their effects and the pressures that drive those activities is therefore required. However, a guiding principle of the UN Agenda for Sustainable Development is that global problems require local action. Thus, indicators must provide information for policymakers as well as guidance for farmers and other practitioners. Many indicator programmes currently proposed do not provide this level of guidance as no evaluation as to what level of activity is sustainable has been agreed. A model is presented, to show how scientific and political or participatory approaches may be combined to meet the multiple objectives of involving people, maintaining scientific integrity and providing guidance for policymakers and practitioners alike.  相似文献   
124.

India and Canada share a common heritage in natural resources management. Both have a colonial background, settlers and indigenous peoples; there is a history of management agencies with utilitarian attitudes, and a history of treating public lands as commodities for commerce rather than as resources for local livelihoods. This historical context guided the overall goal of this study, which was policy development for the sustainable use of mountain environments. Interviews, workshops and seminars were held with local people and resource management professionals in a comparative case study in two regions; the Kullu area in Himachal Pradesh, India and the Arrow Lakes area in British Columbia, Canada. The paper is organized around two main objectives of the work relating to the successes and failures of mountain environment resource management policies and the development of criteria for assessing and monitoring sustainability in mountain environments, in particular, criteria for examining relevant crosscultural dimensions of sustainable development in these environments. By way of conclusion the paper considers further ways in which traditional resource policy development and implementation is being challenged by changing values and priorities; ecosystems management with people; and co-management and public participation.  相似文献   
125.
SUMMARY

Criterion 4 of the Montreal Process addresses the conservation of soil and water resources as a way to assess the sustainability of a nation's forests. For the most part, the indicators under this criterion are relevant to rangelands. The area and percent of rangeland with significant soil erosion apply equally well to both biomes. Percent of streams with flow rates and timing outside its range of historical variation is also equally important, although a measure of proper functioning and condition may provide a better measure of the indicator. The area and percent of rangeland with diminished soil productive capability because of a loss of reduced organic matter or changed physical characteristics can be useful indicators locally and regionally.  相似文献   
126.
This article presents a study of the interrelationships between the different dimensions of sustainability as measured by the sustainable society index framework. We examine the statistical relationships between the four indices making up the sustainable society index framework. The analysis uses the complete existing data set provided by Sustainable Society Foundation for the years 2006, 2008, 2010 and 2012 and for 151 countries. While the time period where data are available is quite short, we can make some preliminary observations about the apparent trends in the interrelationships of the different dimensions of sustainability. This study shows that the three dimensions of sustainability are far from all being synergic and positively correlated. There is a strong negative correlation between human well-being and environmental well-being. This is problematic from the point of view of the Brundtland Commission’s three-pillar definition of sustainability. However, the trade-off relationship between economic and environmental development measured by the economic well-being index and environmental well-being index is decreasing and the dimensions are becoming more de-linked. This trend is promising from the sustainability perspective.  相似文献   
127.
Human activities are expected to result in a diversity of directional or stochastic constraints that affect species either directly or by indirectly impacting their resources. However, there is no theoretical framework to predict the complex and various effects of these constraints on ecological communities. We developed a dynamic model that mimics the use of different resource types by a community of competing species. We investigated the effects of different environmental constraints (affecting either directly the growth rate of species or having indirect effects on their resources) on several biodiversity indicators. Our results indicate that (i) in realistic community models (assuming uneven resource requirements among species) the effects of perturbations are strongly buffered compared to neutral models; (ii) the species richness of communities can be maximized for intermediate levels of direct constraints (unimodal response), even in the absence of trade-off between competitive ability and tolerance to constraints; (iii) no such unimodal response occurs with indirect constraints; (iv) an increase in the environmental (e.g., climatic) variance may have different effects on community biomass and species richness.  相似文献   
128.
This paper presents a Business Recovery Assessment Framework (BRAF) to help researchers and practitioners design robust, repeatable, and comparable studies of business recovery in various post‐disruption contexts. Studies assessing business recovery without adequately considering the research aims, recovery definitions, and indicators can produce misleading findings. The BRAF is composed of a series of steps that guide the decisions that researchers need to make to ensure: (i) that recovery is indeed being measured; (ii) that the indicators of recovery that are selected align with the objectives of the study and the definition of recovery; and, where necessary, (iii) that appropriate comparative control variables are in place. The paper draws on a large dataset of business surveys collected following the earthquakes in Canterbury, New Zealand, on 4 September 2010 and 22 February 2011 to demonstrate the varied conclusions that different recovery indicators can produce and to justify the need for a systematic approach to business recovery assessments.  相似文献   
129.
Understanding how data uncertainty influences ecosystem analysis is critical as we move toward ecosystem-based management. Here, we investigate how 18 Ecological Network Analysis (ENA) indicators that characterize ecosystem growth, development, and condition are affected by uncertainty in an ecosystem model of Lake Sidney Lanier (USA). We applied ENA to 122 plausible parameterizations of the ecosystem developed by Borrett and Osidele (2007, Ecological Modelling 200, 371-387), and then used the coefficient of variation (CV) to compare system indicator variability. We considered Total System Throughput (TST) as a measure of the underlying model uncertainty and tested three hypotheses. First, we hypothesized that non-ratio indicators whose calculation includes the TST would be at least as variable as TST if not more variable. Second, we postulated that indicators calculated as ratios, with TST in the numerator and denominator would tend to be less variable than TST because its influence will cancel. Last, we expected the Average Mutual Information (AMI) to be less variable than TST because it is a bounded function. Our work shows that the 18 indicators grouped into four categories. The first group has significantly larger CVs than the CV for TST. In this group, model uncertainty is amplified rendering these three indicators less useful. The second group of four indicators shows no significant difference in variability with respect to TST. Finally, there are two groups whose CV values are significantly lower than that for TST. The least variable group includes the ratio-based indicators and Average Mutual Information. Due to their low variability, we conclude that these indicators are the most robust to the parameter uncertainty and most useful for ecosystem assessment and comparative ecosystem analysis. In summary, this work suggests that we can be as certain, or more certain, in most of the selected ENA indicators as we are in the parameters of the model analyzed.  相似文献   
130.
为分析煤自燃早期气体指标变化特征规律,更好地解决煤矿现场灭火救灾决策问题,通过煤自燃程序升温试验,首先得到煤样气氛中O2,CO,CO2,CH4,C2H4和C2H6气体的体积分数随温度的变化规律。根据煤体温度,将煤自燃前期划分为5个阶段(潜伏、储热、蒸发、活跃和乏氧)。分析3种不同变质程度的煤样的气体指标在各阶段的变化特征。建立煤自燃气体指标与特征温度阶段区间的对应关系。结果表明:在自燃潜伏阶段,煤的变质程度越低,早期越易产生CO,越难产生CH4;在储热阶段,煤的变质程度越低,早期越易且越快产生C2H6;在蒸发阶段,煤内外在水分脱附,低变质煤的C2H4也随之产生;在活跃阶段,各种气体体积分数均有剧烈增高的趋势,较高变质煤的C2H4也随之产生;在乏氧阶段,O2体积分数低于15%,与O2体积分数相关指标(CO/ΔO2,CO/CO2等)趋势有所改变。  相似文献   
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