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101.
The recycling of municipal solid waste has a remarkable importance in the preservation of the environment and the welfare of the society. However, it is also important that this service can be provided with efficient costs. This paper aims to search for economies of output density and economies of size in the selective collection and recycling activities in Portugal and to identify the size the utilities should have to become more cost efficient. The sample comprises all Portuguese recycling utilities operating in the wholesale segment in the period 2006–2010. The results show that the Portuguese recycling utilities should increase the quantities of municipal solid waste for recycling (especially glass and paper) and also become larger to dimensions corresponding to a supply of 400–550 thousand inhabitants. With the increasing amount of glass collected, utilities are simultaneously struggling to fulfill the targets established by the European legislation and explore the existing economies of output density. The results also show that the management of these services carried out by private companies and the use of incineration (by utilities) seem to reduce the costs of utilities while the regulation of these services and the composting of waste held by utilities tend to increase costs.  相似文献   
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Our aim was to explore the adaptation choices to climate change in the grapevine regions of Spain from two points of view. First, what are the main reasons for concern? Second, how large is the adaptation effort in each region? We address the first question by measuring sensitivity to climate change with Huglin, Cold Night and Dryness Indices over the entire territory, providing information on the adaptation type (e.g. varieties, zoning, water allocation). We then estimate probabilistic projections across scenario, zone and sensitivity indices in the 56 Protected Designation of Origin areas to inform on the magnitude of the adaptation effort. Second, we propose an adaptation effort measure that is framed according to the local environmental context. Results suggest that most areas urgently need an adaptation plan due to the deterioration of production and quality indices as a result of climate change. Potential opportunities in many climate regions might be limited by current policy. The production objectives of quality and quantity trade-offs will probably need to be revised by analysing the sustainability of grapevine production.  相似文献   
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This synthesis article joins the authors of the special issue “Gender perspectives in resilience, vulnerability and adaptation to global environmental change” in a common reflective dialogue about the main contributions of their papers. In sum, here we reflect on links between gender and feminist approaches to research in adaptation and resilience in global environmental change (GEC). The main theoretical contributions of this special issue are threefold: emphasizing the relevance of power relations in feminist political ecology, bringing the livelihood and intersectionality approaches into GEC, and linking resilience theories and critical feminist research. Empirical insights on key debates in GEC studies are also highlighted from the nine cases analysed, from Europe, the Americas, Asia, Africa and the Pacific. Further, the special issue also contributes to broaden the gender approach in adaptation to GEC by incorporating research sites in the Global North alongside sites from the Global South. This paper examines and compares the main approaches adopted (e.g. qualitative or mixed methods) and the methodological challenges that derive from intersectional perspectives. Finally, key messages for policy agendas and further research are drawn from the common reflection.  相似文献   
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Regional Environmental Change - This paper examines barriers and opportunities for climate change adaptation in an urban coastal setting where adaptation is in its infancy. It draws on a diagnostic...  相似文献   
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The European Water Framework Directive (WFD) establishes a well differentiated typology of water bodies on the basis of scientific and biological criteria. For coastal waters, such criteria have long been established, while for transitional waters they are still under discussion. One of the difficulties when applying the WFD to coastal lagoons is to include them in only one of these categories, and while there is no doubt about the nature of estuaries as transitional waters, there is some controversy concerning lagoons. To what extent, reference conditions may be similar for estuaries and lagoons, or whether features common to all coastal lagoons are more important for differentiating them from other water bodies than the fact that there is (or is not) any fresh water influence, is something that remains unclear and is discussed in this work. Coastal lagoons and estuaries form part of a continuum between continental and marine aquatic ecosystems. Shelter, strong boundaries or gradients with adjacent ecosystems, anomalies in salinity regarding freshwater or marine ecosystems, shallowness, etc. all contribute to the high biological productivity of estuaries and lagoons and determine common ecological guilds in the species inhabiting them. On the other hand, fresh water influence, the spatial organization of gradients and environmental variability (longitudinal one-dimensional gradients in estuaries versus complex patterns and three-dimensional heterogeneity in lagoons) constitute the main differences, since these factors affect both the species composition and the dominance of certain ecological guilds and, probably, the system’s complexity and homeostatic capability. In the context of the WFD, coastal lagoons and estuaries are closer to each other than they are to continental or marine waters, and, on the basis of the shared features, they could be intercalibrated and managed together. However, coastal lagoons cannot be considered transitional waters according to the present definition. To assume that fresh water influence is an inherent characteristic to these ecosystems could lead to important changes in the ecological organization and functioning of coastal lagoons where natural fresh water input is low or null. In our opinion, the present day definition of transitional waters should be changed substituting the criterion of fresh water influence by another based on common features, such as relative isolation and anomalies in salinity in water bodies with marine influence. Otherwise, coastal lagoons should be considered a particularly characteristic type of water mass for establishing reference conditions of ecological status.  相似文献   
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With the potential expansion of forest conservation programs spurred by climate-change agreements, there is a need to measure the extent to which such programs achieve their intended results. Conventional methods for evaluating conservation impact tend to be biased because they do not compare like areas or account for spatial relations. We assessed the effect of a conservation initiative that combined designation of protected areas with payments for environmental services to conserve over wintering habitat for the monarch butterfly (Danaus plexippus) in Mexico. To do so, we used a spatial-matching estimator that matches covariates among polygons and their neighbors. We measured avoided forest loss (avoided disturbance and deforestation) by comparing forest cover on protected and unprotected lands that were similar in terms of accessibility, governance, and forest type. Whereas conventional estimates of avoided forest loss suggest that conservation initiatives did not protect forest cover, we found evidence that the conservation measures are preserving forest cover. We found that the conservation measures protected between 200 ha and 710 ha (3-16%) of forest that is high-quality habitat for monarch butterflies, but had a smaller effect on total forest cover, preserving between 0 ha and 200 ha (0-2.5%) of forest with canopy cover >70%. We suggest that future estimates of avoided forest loss be analyzed spatially to account for how forest loss occurs across the landscape. Given the forthcoming demand from donors and carbon financiers for estimates of avoided forest loss, we anticipate our methods and results will contribute to future studies that estimate the outcome of conservation efforts.  相似文献   
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