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221.
Assessing the environmental impact due to consumption of goods and services is a pivotal step towards achieving the sustainable development goal related to responsible production and consumption (i.e. SDG 12). Household appliances plays a crucial role and should be assessed in a systemic manner, namely considering all life cycle stages, technological efficiency, and affluence aspects. The present study assess the impact of such household appliances used in Europe, and tests scenarios of potential impact reduction at various scales. Life cycle assessment is applied to 14 different household appliances (ranging from dishwashers to television devices) selected to build a set of representative products, based on their economic value and diffusion in households in Europe. Related impacts are calculated with the Environmental Footprint method for calculating a Consumer Footprint “appliances” for the baseline year 2010. A number of scenarios encompassing eco-solutions on a technical level, changes in consumption pattern, behavioral changes, as well as the combination of all these aspects are run to estimate the Consumer Footprint related to household appliances for the year 2030, compared against this baseline scenario. The baseline Consumer Footprint is confirming the importance of the use phase in leading the impacts in almost all impact categories. Testing different scenarios concludes that there is a reduction of the impact for most of the categories (with up to 67% for the ozone depletion potential, and still around 35% for the global warming potential), while two of the here examined impact categories (i.e. land-use and mineral resource depletion) show an overall potential that is even negative – i.e. the results of all scenarios are higher than the ones of the 2010 baseline scenario. The increase in purchase and use of such appliances may offset energy efficiency benefits in some of the examined categories. Hence, the assessment of sustainability of appliances consumption should always include several scales, from the efficiency of the products (micro scale), to the improvement of the energy mix (meso scale), up to accounting for socio-economic drivers and patterns of consumption affecting the overall appliances stock (macro scale).  相似文献   
222.
The twin facets of urban hydraulic reach - cities’ appropriation of water from surrounding regions and irrigation use of urban wastewater over a growing rural footprint - form an emerging global policy challenge, especially as democratizing societies seek institutional means to address both urban growth and water scarcity. A central concern of this paper is to demonstrate that policy regionalism, as a process-based understanding of institutions and decision-making, better explains the causes, forms, and outcomes of hydraulic reach than do more structural approaches. Hermosillo, Mexico presents an unfolding case of rural-urban tension for control over rivers and aquifers as well as the infrastructure for water capture, storage, conveyance, and wastewater release. The analysis employs process documentation of water transfer and wastewater negotiations through interviews, review of primary documents, and field observations. Hermosillo’s recourse to negotiated agreements and quasi-market transactions, led by an emerging group of public sector innovators, advances understanding of water policy in Mexico by moving beyond prevailing concerns with the water reform’s neoliberal underpinnings to exploration of rapidly changing urban-centered experimentation. We conclude that evolving urban-rural power disparities and water resource landscapes of urban growth will drive continued expansion of hydraulic reach in water-scarce regions globally.  相似文献   
223.
As marine spatial planning is developing, prompted by the European Union through common principles prescribed in a road map, it is important to disseminate and analyse what has been put forward as the French experience in this field. Hence, the experience of the schémas de mise en valeur de la mer immediately proves to be original in its framework and deeply rooted in French specificities. However, a further analysis of this procedure implemented over several decades highlights the perspectives that would be worth integrating into French and European considerations. This paper thus provides information referring to the SMVM experience, presents an analysis of its results, and attempts to draw lessons from it with regard to recent developments in French marine policy.  相似文献   
224.
Ireland's waters represent a valuable resource encompassing productive fishing grounds and important oil and gas reserves. As a species rich marine environment, Ireland's waters are also an important habitat for many species of marine mammal. Specifically, grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina) are widespread in Irish coastal waters and at least 24 species of cetacean have been reported at sea. The coastal zone represents critical habitat for many of these species, in particular seals that use both terrestrial and aquatic coastal habitat and are vulnerable to habitat degradation. Increasing exploitation of marine resources has increased their exposure to a range of anthropogenic effects including pollution and habitat loss. As top predators seals interact with commercial fisheries both directly and indirectly for resources and conflicts arise. The relatively recent move towards ‘greener’ resource exploitation such as marine renewable energy does not come without negative consequences for marine mammals including seals, which are afforded protection under national and international conservation legislation, highlighting the difficulties faced by resource managers. The sustainable exploitation of resources whilst conserving biodiversity is a challenging task and effective management implementation depends on appropriate policy informed by reliable scientific data. This paper outlines the conservation needs of seals in Irish waters, reviews our current knowledge of these species in Irish water, provides a critical analysis of the existing legislative framework and describes how research outputs can inform present and future policy decisions.  相似文献   
225.
In this paper, the authors analyze a wide range of recreational management strategies for their impacts on red snapper yield, economic surplus and the fish stock. Simulating a wide range of policies, the authors find Data Envelopment Analysis (DEA) inspired policy efficiency frontiers that lead to finding those management strategies that offer the greatest level of economic surplus for any biological target, looking at both the east and west Gulf of Mexico fisheries. Red snapper has been declared overfished since 1988 and the 2005 SEDAR 7 stock assessment declared red snapper were overfished and undergoing overfishing. In November 2009, the update of the assessment declared that overfishing was no longer occurring but that the red snapper stocks needed to be rebuilt. In this analysis, it was found that red snapper are neither overfished or undergoing overfishing. The main difference between the present model and the SEDAR 7 model is that the latest model uses a higher mortality rate for juveniles and a density dependent model. The authors also suggest that the east and west should be managed as separate units.  相似文献   
226.
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   
227.
以悬停式AUVMM-01为试验平台,设计一种基于行为的控制体系结构。将AUV的行为划分为漫游、巡航和避障三个基本行为,并将模糊控制引入避障行为中,通过基于优先级的仲裁方式实现三种行为的有序协调,完成预定任务。同时,针对AUV的悬停需求,提出了增加内环速度反馈实现AUV稳定悬停的控制方法,定义一种新的高层自治控制系统与底层运动控制系统的接口。最后,通过建立整个系统的Simulink仿真模型,验证了该控制策略的有效性。  相似文献   
228.
关注生态系统服务价值(Ecosystem service value,ESV)与城市化耦合协调互动关系,对黄河流域高质量发展大有裨益。文章运用熵权法、耦合协调模型、空间自相关模型,障碍度模型分析了城市化与ESV的耦合协调关系及主导障碍因素。结果表明:(1)1995—2018年,黄河流域ESV发生了很大的改善,整体增加了33.05×109元,且以调节服务为主导,草地、林地、耕地服务价值对总ESV贡献率较高。单位面积生态系统服务价值(PE)呈现南高北低、中游高上下游低的空间格局。(2)PE与城市化耦合协调度(Coupling coordination degree,CCD)逐渐改善,轻度耦合协调增加了27.12%,严重失调类型减少了45.46%,耦合亚型从城市化滞后型转变为ESV滞后型;从空间上看,CCD呈现南高北低、中游优于上游和下游的空间格局,协调度具有显著的空间正相关性,存在明显的高-高和低-低集聚特征,高-高集聚区主要分布在ESV高且城市化水平相对较高的中游和下游地区,低-低集聚区主要分布在ESV较低的上游地区。(3)1995—2018年主导障碍因素未发生明显...  相似文献   
229.
通过构建汾河流域城市化与水资源系统指标体系,利用综合评价法对2010—2019年汾河流域城市化和水资源综合水平的变化趋势进行分析,在此基础上构建耦合协调度模型,分析汾河流域城市化与水资源的耦合协调关系。结果表明:汾河流域城市化综合指数整体呈上升趋势,城市化子系统重要程度表现为经济城市化>社会城市化>空间城市化>人口城市化;水资源综合指数呈波动上升趋势,水资源子系统重要程度呈现出水资源利用>水资源水平>水资源保护,水资源环境不断优化,2013年出现短期下降,主要受水资源量和用水量等要素的影响;从时间上看,2010—2019年汾河流域城市化与水资源耦合协调度不断提高,经历了从2010年低水平轻度失调到2019年高水平协调发展过程;空间上,2010—2019年汾河流域六市城市化与水资源耦合协调度不断提升,吕梁、太原、忻州达到良好协调水平,临汾、运城处于勉强协调水平,而晋中则处于磨合阶段的濒临失调水平。  相似文献   
230.
经济新常态下河南省产业结构与水资源耦合协调发展研究   总被引:1,自引:1,他引:0  
在经济新常态背景下,为探讨产业结构和水资源的协调发展关系,构建了产业结构和水资源两个系统的三级指标评价体系,通过数值标准化处理、指标权重计算,运用综合评价指数模型以及耦合协调度模型,分析了河南省2005~2016年水资源和产业结构的综合评价指数、耦合协调度的时空变化特征。结果表明:(1)河南省产业结构和水资源综合评价指数均呈上升趋势,反映了河南省产业结构不断优化、水资源综合利用水平不断提高;(2)河南省城市发展由产业结构水平滞后型转化为水资源水平滞后型,直至转化为同步发展型等三个类型;(3)河南省产业结构与水资源系统的耦合关系是动态演变过程,逐步从初级耦合协调、中级耦合协调发展到高级耦合协调,城市耦合协调水平大幅度提升,2016年18个城市全部处于中高级耦合协调;(4)河南省各市产业结构与水资源耦合协调度不断提高,逐步实现了由初、中级耦合协调分布较集中向豫中、豫西、豫南、豫北高级耦合协调分布的转变。  相似文献   
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