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571.
The development of environmental performance policy indicators for public services, and in particular for the defence sector, is an emerging issue. Despite a number of recent initiatives there has been little work done in this area, since the other sectors usually focused on are agriculture, transport, industry, tourism and energy. This type of tool can be an important component for environmental performance evaluation at policy level, when integrated in the general performance assessment system of public missions and activities. The main objective of this research was to develop environmental performance policy indicators for the public sector, specifically applied to the defence sector. Previous research included an assessment of the environmental profile, through the evaluation of how environmental management practices have been adopted in this sector and an assessment of environmental aspects and impacts. This paper builds upon that previous research, developing an indicator framework--SEPI--supported by the selection and construction of environmental performance indicators. Another aim is to discuss how the current environmental indicator framework can be integrated into overall performance management. The Portuguese defence sector is presented and the usefulness of this methodology demonstrated. Feasibility and relevancy criteria are applied to evaluate the set of indicators proposed, allowing indicators to be scored and indicators for the policy level to be obtained.  相似文献   
572.

为了对比北京市和呼和浩特市空气质量,探讨其差异性成因及防治对策,收集2市2014—2019年的空气质量常规监测数据,对空气污染物浓度、首要污染物变化及空气质量指数等特征进行分析。结果表明:北京和呼和浩特2市空气中PM10、PM2.5、SO2、NO2、CO这5种污染物浓度表现出相似的季节变化特征,空气质量冬季最差,夏季最好;2市空气中污染物都是以颗粒物为主,其中北京市以PM2.5为主,呼和浩特市以PM10为主;长期监测数据显示,2市在经济社会快速发展的同时,污染物浓度大多呈持续下降的趋势,但O3浓度有所增加。从2市各经济指标和污染物浓度变化的相关性看出,城市高质量发展越来越受到城市空气质量的约束,而改善城市经济结构在空气污染防治中具有极大作用。

  相似文献   
573.
城市土地资源可持续利用评价指标体系构建   总被引:2,自引:0,他引:2  
土地资源可持续发展的核心内容是如何将一个概念转换成可操作的管理模式,即建立一套切实可行的指标体系。目前,我国关于土地可持续发展的指标体系评价处于探索阶段,还没有形成一套较成熟的评价方法。基于对于我国土地可持续发展的指标体系研究,构建了一套有关城市土地可持续利用的评价指标体系。  相似文献   
574.
At the global scale, biodiversity indicators are typically used to monitor general trends, but are rarely implemented with specific purpose or linked directly to decision making. Some indicators are better suited to predicting future change, others are more appropriate for evaluating past actions, but this is seldom made explicit. We developed a conceptual model for assigning biodiversity indicators to appropriate functions based on a common approach used in economics. Using the model, indicators can be classified as leading (indicators that change before the subject of interest, informing preventative actions), coincident (indicators that measure the subject of interest), or lagging (indicators that change after the subject of interest has changed and thus can be used to evaluate past actions). We classified indicators based on ecological theory on biodiversity response times and management objectives in 2 case studies: global species extinction and marine ecosystem collapse. For global species extinctions, indicators of abundance (e.g., the Living Planet Index or biodiversity intactness index) were most likely to respond first, as leading indicators that inform preventative action, while extinction indicators were expected to respond slowly, acting as lagging indicators flagging the need for evaluation. For marine ecosystem collapse, indicators of direct responses to fishing were expected to be leading, while those measuring ecosystem collapse could be lagging. Classification defines an active role for indicators within the policy cycle, creates an explicit link to preventative decision-making, and supports preventative action.  相似文献   
575.

Agricultural systems have become increasingly industrialized and mechanized, relying on machinery and chemical inputs, rather than people and natural processes, to increase yields of food. The trend towards an increasingly globalised food system encourages unsustainable transportation of food around the world. Agricultural intensification and the globalisation of the agrofood chain has resulted in adverse environmental, social and economic consequences impeding moves towards sustainability. Organic farming can overcome many of the environmental problems associated with agricultural intensification. However, it does not have the potential to fully address the social and economic problems caused by the globalisation of the food system. Organic farming must be combined with local and regional sourcing of food products, for instance through forms of direct marketing of organic produce. Direct marketing schemes such as farmers' markets, food box delivery schemes and community-supported agriculture are all projects which, if managed with sustainability as the prime objective, have the potential to move towards a more socially, environmentally and economically sustainable agrofood system.  相似文献   
576.
Sustainability science represents a fundamental shift in the nature of research on environmental problems, calling for specialists to expand beyond their disciplinary perspectives in order to cooperate together to understand and address systemic problems. This shift demands a corresponding shift in education in order to equip students with the skills, theories, and methods they need to address contemporary challenges. We argue that case studies are a productive pedagogical approach to teaching about sustainability and teaching for sustainability. Case-based approaches equip students to encounter complexity, manage uncertainty, and generate innovative strategies. In laying out of the pedagogical challenges inherent in sustainability education, we highlight opportunities and demands for environmental communication scholars to contribute to the emerging discipline of sustainability science.  相似文献   
577.
The United Nations General Assembly agreed and approved in September 2015 the document ‘2030 Agenda for Sustainable Development’, which contains a set of measures aiming to balance economic progress and protection of the environment, whilst at the same time remain aware of the need to address the many disparities still seen between industrialised and developing countries. The Agenda document consists of 17 Sustainable Development Goals (SDGs), which among many other tasks, intend to eradicate poverty and create better health conditions in both developed and developing countries. But despite the need for and the relevance of the SDGs, it is unclear how they may help to address present and future sustainability challenges. Based on the need to shed some light on such a relationship, this paper describes each of the SDGs, and offers an analysis of the extent to which their implementation may offer support to ongoing attempts to handle some of the pressing problems seen in pursuing sustainable development. Three case studies are presented to show in practice how best the SDGs can be handled. The paper concludes that the process of implementing the SDGs offers unrivalled opportunities to advance equal opportunity and foster economic empowerment, helping countries to promote the cause of sustainable development in their territories, hence benefiting their populations.  相似文献   
578.
Wetland assessment has been a popular field of research worldwide. However, various indicators have been used in wetland assessment for different purposes and backgrounds and also because of the research limitations. Therefore, a more comprehensive, sound, and efficient indicator system is needed for researchers’ referencing to evaluate wetlands. After an extensive review of wetland assessment literatures, the reported indicators were evaluated using the developed assessment system, based on the Analytical Hierarchy Process (AHP) with three main goals: nature protection, function utilization, and sustainable development. Each indicator was evaluated using two methods. The first method was to study the percentage of the indicator application, and the second was to assess the weighted ratios assigned to the indicators according to principles of comparability, typicality, sensibility, and availability. The results of these two methods were compared to study the commonalities and specialties of the indicators. They also showed that some indicators were widely used, including biodiversity, weather and climate, hydrological change, and the output of wetland. On the other hand, other sustainable indicators were easily ignored, such as environmental carrying capacity and wetland planning. Furthermore, an indicator system for wetland assessment was structured and strategized to discuss how to choose indicators for wetland assessment under different conditions. The proposed approach can be used to guide the process of wetland assessments in the future.  相似文献   
579.
特种生物标志物作为溢油指示物(或指标)的研究   总被引:4,自引:1,他引:4  
用毛细管GC-MS对不同水环境中不同油类的特种生物标志物进行检测,结果表明,异戊二烯烷烃类姥鲛烷与植烷的比值在两个多月的风化过程中不受风化的影响;萜烷和甾烷的某些比值参数在一年的风化过程中(或室内自然放置4年)不受风化的影响。姥鲛烷与植烷的比值可以作为风化两个多月的溢油指示物(或指标);萜烷和甾烷比值可以作为风化一年(或室内自然放置4年)的溢油指示物(或指标)。  相似文献   
580.
Nature-based solutions (NBS) were introduced as integrated, multifunctional and multi-beneficial solutions to a wide array of socio-ecological challenges. Although principles for a common understanding and implementation of NBS were already developed on a landscape scale, specific principles are needed with regard to an application in urban areas. Urban areas come with particular challenges including (i) spatial conflicts with urban system nestedness, (ii) specific urban biodiversity, fragmentation and altered environments, (iii) value plurality, multi-actor interdependencies and environmental injustices, (iv) path-dependencies with cultural and planning legacies and (v) a potential misconception of cities as being artificial landscapes disconnected from nature. Given these challenges, in this perspective paper, we build upon and integrate knowledge from the most recent academic work on NBS in urban areas and introduce five distinct, integrated principles for urban NBS design, planning and implementation. Our five principles should help to transcend governance gaps and advance the scientific discourse of urban NBS towards a more effective and sustainable urban development. To contribute to resilient urban futures, the design, planning, policy and governance of NBS should (1) consider the need for a systemic understanding, (2) contribute to benefiting people and biodiversity, (3) contribute to inclusive solutions for the long-term, (4) consider context conditions and (5) foster communication and learning.  相似文献   
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