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121.
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While public health and urban planning were closely linked in the past, today both domains are institutionally separate. In most cases, health intersects with spatial planning processes only through obligatory evaluations, such as environmental impact assessments, or restrictive environmental legislation. This institutionalisation of health criteria in most western countries has difficulty in dealing with recent environmental health challenges, leading to continual distrust and conflict between citizens and the government. This impasse has recently been discussed by academics who acknowledge the complexity of both city and health issues. It seems, however, that the full extent of the issue has not been covered yet, leading to recommendations and frameworks that are useful but fixed and retrospective. This paper moves beyond those fixed frameworks to develop a better understanding of the complexity of the current disconnect and explores ideas for a future planning approach, grounded on new ideas of co-evolutionary and adaptive planning.  相似文献   
123.
We propose a method for the appropriate assessment of adverse effects of roads in compliance with the European Union Habitats Directive. The method incorporates an analysis of ecological risk of edge effects by the proposed roads with the related increase in accessibility. The method was tested on 30 km of planned forest roads inside an 8,000-ha reserve included in two Natura 2000 sites. As a result, the cumulative effect of 19 road segments was judged as not significantly affecting the integrity of the sites, although they made accessible an extra 314 ha. On the basis of the accessibility calculation, 20 ha of land were set aside from forest exploitation as a mandatory mitigation measure. The method objectively determined the cumulative adverse effects, enabled comparison of plan revisions and alternatives and proved to measure direct and indirect significant effects with a realistic effort in terms of field survey and geographic information system processing.  相似文献   
124.

Waste-activated sludge (WAS) may be considered a resource generated by wastewater treatment plants and used for biogas-generation but it requires pre-treatment (PT) for enhanced biogas-yields and reduced WAS disposal costs. To date, a number of studies on the optimization of such PT focused on improved biogas yields but neglected inferred energy and resource consumption. Here, we aimed to identify the most promising thermo-chemical PT-strategy in terms of net energy output and cost-efficiency by optimizing PT temperature and the amount and sort of the alkaline reagent used. We compared methane-potentials and disposal costs of untreated and treated WAS and conducted an annual cost-benefit calculation. We defined 70 °C and 0.04 M NaOH as ideal PT-conditions being both, low-energy demanding and efficient. Applying these conditions, enhanced biogas-yields and improved dewaterability led to reduced electricity and disposal costs of 22 and 27%, respectively, resulting in savings of approx. 28% of the yearly WAS-related expenditures of a wastewater treatment plant. Despite multiple benefits in running costs, the implementation of WAS-PT was not recommendable in the presented case study due to high investment costs.

  相似文献   
125.
We examine the wider social knowledge domain that complements technical and environmental knowledge in enabling adaptive practices through two case studies in Tanzania. We are concerned with knowledge production that is shaped by gendered exclusion from the main thrusts of planned adaptation, in the practice of irrigation in a dryland village and the adoption of fast-maturing seed varieties in a highland village. The findings draw on data from a household survey, community workshops, and key informant interviews. The largest challenge to effective adaptation is a lack of access to the social networks and institutions that allocate resources needed for adaptation. Results demonstrate the social differentiation of local knowledge, and how it is entwined with adaptive practices that emerge in relation to gendered mechanisms of access. We conclude that community-based adaptation can learn from engaging the broader social knowledge base in evaluating priorities for coping with greater climate variability.  相似文献   
126.
The measurement of hydrochloric acid (HCl) on a continuous basis in coal-fired plants is expected to become more important if HCl standards become implemented as part of the Federal Mercury and Air Toxics Standards (MATS) standards that are under consideration. For this study, the operational performance of three methods/instruments, including tunable diode laser absorption spectroscopy (TDLAS), cavity ring down spectroscopy (CRDS), and Fourier transform infrared (FTIR) spectroscopy, were evaluated over a range of real-world operating environments. Evaluations were done over an HCl concentration range of 0–25 ppmv and temperatures of 25, 100, and 185 °C. The average differences with respect to temperature were 3.0% for the TDL for values over 2.0 ppmv and 6.9% of all concentrations, 3.3% for the CRDS, and 4.5% for the FTIR. Interference tests for H2O, SO2, and CO, CO2, and NO for a range of concentrations typical of flue gases from coal-fired power plants did not show any strong interferences. The possible exception was an interference from H2O with the FTIR. The instrument average precision over the entire range was 4.4% for the TDL with better precision seen for concentrations levels of 2.0 ppmv and above, 2.5% for the CRDS, and 3.5% for the FTIR. The minimum detection limits were all on the order of 0.25 ppmv, or less, utilizing the TDL values with a 5-m path. Zero drift was found to be 1.48% for the TDL, 0.88% for the CRDS, and 1.28% for the FTIR.

Implications: This study provides an evaluation of the operational performance of three methods/instruments, including TDL absorption spectroscopy (TDLAS), cavity ring down spectroscopy (CRDS), and FTIR spectroscopy, for the measurement of hydrochloric acid (HCl) over a range of real-world operating environments. The results showed good instrument accuracy as a function of temperature and no strong interferences for flue gases typical to coal-fired power plants. The results show that these instruments would be viable for the measurement of HCl in coal-fired plants if HCl standards become implemented as part of the Federal Mercury and Air Toxics Standards (MATS) standards that are under consideration.  相似文献   

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Ecological science contributes to solving a broad range of environmental problems. However, lack of ecological literacy in practice often limits application of this knowledge. In this paper, we highlight a critical but often overlooked demand on ecological literacy: to enable professionals of various careers to apply scientific knowledge when faced with environmental problems. Current university courses on ecology often fail to persuade students that ecological science provides important tools for environmental problem solving. We propose problem-based learning to improve the understanding of ecological science and its usefulness for real-world environmental issues that professionals in careers as diverse as engineering, public health, architecture, social sciences, or management will address. Courses should set clear learning objectives for cognitive skills they expect students to acquire. Thus, professionals in different fields will be enabled to improve environmental decision-making processes and to participate effectively in multidisciplinary work groups charged with tackling environmental issues.  相似文献   
130.
Sea ice continues to decline across many regions of the Arctic, with remaining ice becoming increasingly younger and more dynamic. These changes alter the habitats of microbial life that live within the sea ice, which support healthy functioning of the marine ecosystem and provision of resources for human-consumption, in addition to influencing biogeochemical cycles (e.g. air–sea CO2 exchange). With the susceptibility of sea ice ecosystems to climate change, there is a pressing need to fill knowledge gaps surrounding sea ice habitats and their microbial communities. Of fundamental importance to this goal is the development of new methodologies that permit effective study of them. Based on outcomes from the DiatomARCTIC project, this paper integrates existing knowledge with case studies to provide insight on how to best document sea ice microbial communities, which contributes to the sustainable use and protection of Arctic marine and coastal ecosystems in a time of environmental change.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01658-z.  相似文献   
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