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41.
42.

Understanding agreement and differences between land use visions forms a first step for assessing and comparing alternative pathways towards a sustainable future. This study presents an analysis of 20 semi-structured interviews with representatives of the principal land use sectors in Scotland. The aim was to understand what, in their ideal vision, they would want rural Scotland to look like in 2050. Inductive content analysis was used to identify similarities and differences amongst interviewees. There was general agreement on the following: the importance of the environment; the wish for more partnerships, dialogue and collaboration; the desire for society to be more engaged and aware about land use; and a strong need for short-, medium- and long-term policies helping to achieve these goals. The most notable differences relate to land ownership and governance. The outcomes form a basis for further facilitated discussions, emphasising common ground and exploring where, how and to what degree land use sectors can prepare and plan in the light of uncertainties posed by Brexit and climate change. The method was effective for understanding commonalities and differences between stakeholder groups and is transferable to other countries or regions.

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43.
This study compared the environmental impacts of composting yard wastes in windrows with using them in place of soil as alternative daily cover (ADC) in landfills. The Life Cycle Assessment was made using the SimaPro LCA software and showed that the ADC scenario is more beneficial for the environment than windrow composting. ADC use is also a less costly means of disposal of yard wastes. This finding applies only in cases where there are sanitary landfills in the area that are equipped with gas collection systems and can use yard wastes as alternative daily cover. Otherwise, the environmentally preferable method for disposal of source-separated yard wastes is composting rather than landfilling.  相似文献   
44.
    

Phosphogypsum (PG) is a large hazardous waste from fertiliser and phosphoric acid industries from which useful products including rare-earth elements (REEs) can be recovered depending on the treatment process. Its conversion to calcium sulphide (CaS) which was achieved at 95% followed by the formation of S, CaCO3 and residue is one of the plausible treatment processes leading to economic and environmental benefits. This study aimed at monitoring selected REEs behaviour during the conversion of (PG) to (CaS). The concentrations of REEs in the raw PG, the produced CaS and the obtained residue were determined after digestion (microwave and traditional acid leaching) using ICP-OES. The effect of CO2 and H2S used in the process of forming CaCO3 and S from PG on the concentrations of REEs was also investigated. Microwave digestion proved to be more effective than traditional acid leaching in the recovery of REEs. Microwave digestion using 3 mL HNO3 + 1 mL HCl was more effective than 1 mL HNO3 + 3 mL in REEs recovery. CaS contained the highest amount of Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, La and Y with values of 2646, 476, 2255, 320, 60.5, 376, 79.8, 1.24, 476, 1185 and 318 µg/g respectively. Based on these findings, the residue could be further processed to recover REEs despite less than 40% decrease in concentration for the majority of REEs observed due to the use of H2S and CO2. CO2 was found to be more suitable as fewer REEs were leached as compared to H2S. All things considered, the obtained residue could be a good secondary source of REEs as it is easier to leach, retained good amount of REEs and lesser impurities.

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45.
Steel slag can be applied as substitute for natural aggregates in construction applications. The material imposes a high pH (typically 12.5) and low redox potential (Eh), which may lead to environmental problems in specific application scenarios. The aim of this study is to investigate the potential of accelerated steel slag carbonation, at relatively low pCO2 pressure (0.2 bar), to improve the environmental pH and the leaching properties of steel slag, with specific focus on the leaching of vanadium. Carbonation experiments are performed in laboratory columns with steel slag under water-saturated and -unsaturated conditions and temperatures between 5 and 90 °C. Two types of steel slag are tested; free lime containing (K3) slag and K1 slag with a very low free lime content. The fresh and carbonated slag samples are investigated using a combination of leaching experiments, geochemical modelling of leaching mechanisms and microscopic/mineralogical analysis, in order to identify the major processes that control the slag pH and resulting V leaching. The major changes in the amount of sequestered CO2 and the resulting pH reduction occurred within 24 h, the free lime containing slag (K3-slag) being more prone to carbonation than the slag with lower free lime content (K1-slag). While carbonation at these conditions was found to occur predominantly at the surface of the slag grains, the formation of cracks was observed in carbonated K3 slag, suggesting that free lime in the interior of slag grains had also reacted. The pH of the K3 slag (originally pH ± 12.5) was reduced by about 1.5 units, while the K1 slag showed a smaller decrease in pH from about 11.7 to 11.1. However, the pH reduction after carbonation of the K3 slag was observed to lead to an increased V-leaching. Vanadium leaching from the K1 slag resulted in levels above the limit values of the Dutch Soil Quality Decree, for both the untreated and carbonated slag. V-leaching from the carbonated K3 slag remained below these limit values at the relatively high pH that remained after carbonation. The V-bearing di-Ca silicate (C2S) phase has been identified as the major source of the V-leaching. It is shown that the dissolution of this mineral is limited in fresh steel slag, but strongly enhanced by carbonation, which causes the observed enhanced release of V from the K3 slag. The obtained insights in the mineral transformation reactions and their effect on pH and V-leaching provide guidance for further improvement of an accelerated carbonation technology.  相似文献   
46.
Too often, mining developments provide short-term jobs and taxes, and long-term environmental and community degradation. The 'precautionary principle', as practised by the European Union and increasingly by other nations, may provide an opportunity for local communities and others who bear the brunt of mining to employ a cautionary approach to mine permitting. Using the case of the Zortman-Landusky gold mine in Montana, the article illustrates how the precautionary principle might have precluded the tremendous losses suffered by the Fort Belknap residents who live near the now abandoned mine. The Native Americans and other protestors against the mine were correct in their worries about mine drainage affecting their watercourses and the precautionary principle might have limited mine development. The case also illustrates that economic data on mining companies need to go well beyond simple reclamation bond capability in order to avoid bankruptcy resulting in the neighbours and the government having to pay for clean-up.  相似文献   
47.
48.
Forest fires and adaptation options in Europe   总被引:1,自引:0,他引:1  
This paper presents a quantitative assessment of adaptation options in the context of forest fires in Europe under projected climate change. A standalone fire model (SFM) based on a state-of-the-art large-scale forest fire modelling algorithm is used to explore fuel removal through prescribed burnings and improved fire suppression as adaptation options. The climate change projections are provided by three climate models reflecting the SRES A2 scenario. The SFM’s modelled burned areas for selected test countries in Europe show satisfying agreement with observed data coming from two different sources (European Forest Fire Information System and Global Fire Emissions Database). Our estimation of the potential increase in burned areas in Europe under “no adaptation” scenario is about 200 % by 2090 (compared with 2000–2008). The application of prescribed burnings has the potential to keep that increase below 50 %. Improvements in fire suppression might reduce this impact even further, e.g. boosting the probability of putting out a fire within a day by 10 % would result in about a 30 % decrease in annual burned areas. By taking more adaptation options into consideration, such as using agricultural fields as fire breaks, behavioural changes, and long-term options, burned areas can be potentially reduced further than projected in our analysis.  相似文献   
49.
智能化建筑 =绿色建筑   总被引:1,自引:0,他引:1  
在过去的十年中 ,“智能化建筑”这个术语已经被广泛地用于描述新的高技术建筑物 .这一术语在亚洲已经相当流行 ,那里有许多最大的新建筑建设项目 .智能化建筑的概念自然与对环境无害的“绿色建筑物”有关 .本文对 Brengel技术中心作了介绍 ,它是由美国绿色建筑理事会 (USGBC)能源和环境设计指导 (LEED)绿色建筑评定体系首批认证的 12个建筑物之一 .  相似文献   
50.
In this policy perspective, we outline several conditions to support effective science–policy interaction, with a particular emphasis on improving water governance in transboundary basins. Key conditions include (1) recognizing that science is a crucial but bounded input into water resource decision-making processes; (2) establishing conditions for collaboration and shared commitment among actors; (3) understanding that social or group-learning processes linked to science–policy interaction are enhanced through greater collaboration; (4) accepting that the collaborative production of knowledge about hydrological issues and associated socioeconomic change and institutional responses is essential to build legitimate decision-making processes; and (5) engaging boundary organizations and informal networks of scientists, policy makers, and civil society. We elaborate on these conditions with a diverse set of international examples drawn from a synthesis of our collective experiences in assessing the opportunities and constraints (including the role of power relations) related to governance for water in transboundary settings.  相似文献   
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