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The consumption and production of food products in the municipality of Lisbon in the 1890–1900 decade is assessed with the support of historical cartography and statistical resources. For the first time, food production in a municipality in the turn to the twentieth century is accounted and simultaneously subject of a visual analysis of the land used for agriculture and of the water infrastructures that supported such uses. Agriculture occupied at least 40 % of the territory of the city, while the built environment occupied no more than 16 % of the territory. However, local production of food was far from supplying most of the citizens’ needs, and substantial food imports were needed. In this context, the municipality behaved like a heterotrophic system, highly dependent on the external supply of resources. Moreover, comparing to other European cities at the time Lisbon was facing in the end of the nineteenth century a late and slow transition from an agrarian social metabolism to an industrial one, suggesting that Lisbon was still relatively high-solar-powered as compared to other European cities at the time that were already highly fossil-fuel-powered.  相似文献   

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In order to support authorised discharges of low level radioactive liquid effluent into coastal regions, mathematical models are required to robustly predict radiological impacts on critical groups of current and proposed changes to liquid discharges. The grid model presented here simulates the long term dispersion and transport of radioactivity discharged from the Sellafield site in Cumbria, UK, and the subsequent exposure of critical groups in Cumbria and across the Irish Sea in Northern Ireland. The fine grid of the model allows a good resolution of the seabed sediment distribution. This benefits the predictions for the last decades of low discharge level, when bed sediment can become a source of contamination by bringing back the legacy of past high discharges. This is highlighted by the dose comparison, where the predicted dose to Cumbria critical group follows well the dose estimated from environmental data during the low discharge level period.  相似文献   

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While progress has been made in reducing external nutrient inputs to the Baltic Sea, further actions are needed to meet the goals of the Baltic Sea Action Plan (BSAP), especially for the Baltic Proper, Gulf of Finland, and Gulf of Riga sub-basins. We used the net anthropogenic nitrogen and phosphorus inputs (NANI and NAPI, respectively) nutrient accounting approach to construct three scenarios of reduced NANI-NAPI. Reductions assumed that manure nutrients were redistributed from areas with intense animal production to areas that focus on crop production and would otherwise import synthetic and mineral fertilizers. We also used the Simple as Necessary Baltic Long Term Large Scale (SANBALTS) model to compare eutrophication conditions for the scenarios to current and BSAP-target conditions. The scenarios suggest that reducing NANI-NAPI by redistributing manure nutrients, together with improving agronomic practices, could meet 54–82% of the N reductions targets (28–43 kt N reduction) and 38–64% P reduction targets (4–6.6 kt P reduction), depending on scenario. SANBALTS output showed that even partial fulfillment of nutrient reduction targets could have ameliorating effects on eutrophication conditions. Meeting BSAP targets will require addressing additional sources, such as sewage. A common approach to apportioning sources to external nutrients loads could enable further assessment of the feasibility of eutrophication management targets.

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The 1870–1914 globalization period had profound impacts on the international division of labour, with coal-endowed countries specializing in the production of energy-intensive manufacturing goods and others in the production of agricultural goods. This study analyses the environmental consequences of this specialization, by quantifying the flows of energy and hidden energy embodied in the bilateral trade between the UK, the industrial workshop of the world, and Denmark, a coal-poor country with an agricultural economy. We show that the transformations that occurred in Danish agriculture to meet the growing demand for breakfast foods in the UK required significant quantities of feed and coal. Denmark was a net importer of energy throughout the period and a net importer of hidden energy in 1870. However, by the end of this wave of globalization, Denmark had become a significant net exporter of hidden energy to the UK. This was due both to an increase in its land productivity and to the import of coal, grain and fertilizers from abroad.

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While adaptation has received a fair amount of attention in the climate change debate, barriers to adaptation are the focus of a more specific, recent discussion. In this discussion, such barriers are generally treated as having a uniform, negative impact on all actors. However, we argue that the precise nature and impact of such barriers on different actors has so far been largely overlooked. Our study of two drought-prone communities in rural Ethiopia sets out to examine how female- and male-headed households adapt to climate change, particularly focusing on how a variety of barriers influence the choice of adaptation measures to varying extents. To this purpose, we built a conceptual framework based on the Sustainable Livelihood Approach. Data were collected using semi-structured interviews and focus group discussions with male- and female-headed households, community leaders and local extension workers. Our findings suggest that gender-based differences in the choice of adaptation measures at the household level are driven by cultural, social, financial and institutional barriers. Barriers to adaptation—particularly when interacting—have a differentiated impact upon different actors. This outcome hints at the need for donors and policymakers to develop intervention strategies that are sensitive to this fact.  相似文献   

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The likelihood of being faced with trap-like situations is a worrisome aspect of long-term policy-making, such as for climate change adaptation. Even when a policy may be effective in the short-term, changes in problem or policy contexts may render it ineffective over time. The design of ‘robust’ policies, meaning those which are able to self-adjust to linear changes in their environment, can be contrasted with ‘resilient’ ones which are able to adjust not only to linear, but also non-linear shifts in their contexts. Building on Boonstra and de Boer (AMBIO 43:260–274, 2014)’s argument that traps should not be considered as a static phenomenon; rather their emergence and development is often directly influenced by history and path-dependency, this paper elaborates how trap-like situations can emerge with increase in climate uncertainty over time. Three strategies to address policy traps due to climate change form subjects of inquiry in this paper: avoiding traps in the first place, designing against traps, and overcoming traps once in them. Each requires a specific type of design thinking and practice.  相似文献   

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Regional Environmental Change - Paleoecological and paleosocial synthesis, meaning the examination of data and patterns derived from past social and ecological systems, provides an important...  相似文献   

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Tritium (3H or T) is one of the major radionuclides released by nuclear power plants (NPP) into rivers. However, tritiated water (HTO) flux from water to air is seldom considered when assessing health effects of such releases. The aim of this paper is to present the result of a research program, called LORA, conducted on the Loire River (France). To improve our understanding of HTO flux from surface water to air, three field campaigns were organised during the NPP’s radioactive releases to measure simultaneously the activity concentrations in air on the riverbank, using an innovative system, and in river water. The measurements showed that during radioactive releases, water vapour was enriched in 3H. These results were used to calibrate exchange velocities. The average of these estimated exchange velocities was more than one order of magnitude higher than those calculated in the literature from indoor experiments. The variability of these values was also larger, showing that outdoor studies cover a wide range of conditions influencing HTO flux. No correlation was observed between exchanges velocities and meteorological conditions. However, there was a significant difference between day and night with a higher value observed during the day. Two approaches used to calculate HTO evaporation from water (i.e. the approach based on water evaporation and the approach considering that HTO follows its own concentration gradient) were included in a hydrodynamic model, which was used to evaluate HTO air activity along the Loire River. In conclusion, only the approach considering that HTO follows its own gradient led to a good agreement between measurements and predictions. A one-year simulation was done to estimate the contribution of this process to the dose. Its contribution can be considered as negligible in this case compared to the other pathways such as ingestion of water or foodstuffs.  相似文献   

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