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21.
Web-based Public Participation Geographic Information Systems (PPGIS) are increasingly used for surveying place values and informing municipal planning in contexts of urban densification. However, research is lagging behind the rapid deployment of PPGIS applications. Some of the main opportunities and challenges for the uptake and implementation of web-based PPGIS are derived from a literature review and two case studies dealing with municipal planning for urban densification in the Stockholm region, Sweden. A simple clustering analysis identified three interconnected themes that together determine the performance of PPGIS: (i) tool design and affordances; (ii) organisational capacity; and (iii) governance. The results of the case studies augment existing literature regarding the connections between the different socio-technical dimensions for the design, implementation and evaluation of PPGIS applications in municipal planning. A cyborg approach to PPGIS is then proposed to improve the theoretical basis for addressing these dimensions together.  相似文献   
22.
The formation and concentration of disinfection by-products (DBPs) in pool water and the ambient air vary according to the type of water treatment process used. This exploratory study was aimed at investigating the short-term impact of modifications of the water treatment process on traditional DBP levels (e.g., trihalomethanes (THMs), chloramines) and emerging DBPs (e.g., Halonitromethanes, Haloketones, NDMA) in swimming pool water and/or air. A sampling program was carried to understand the impact of the following changes made successively to the standard water treatment process: activation of ultraviolet (UV) photoreactor, halt of air stripping with continuation of air extraction from the buffer tank, halt of air stripping and suppression of air extraction from the buffer tank, suppression of the polyaluminium silicate sulfate (PASS) coagulant. UV caused a high increase of Halonitromethanes (8.4 fold), Haloketones (2.1 fold), and THMs in the water (1.7 fold) and, of THMs in the air (1.6 fold) and contributed to reducing the level of chloramines in the air (1.6 fold) and NDMA in the water (2.1 fold). The results highlight the positive impact of air stripping in reducing volatile contaminants. The PASS did not change the presence of DBPs, except for the THMs, which decrease slightly with the use of this coagulant. This study shows that modifications affecting the water treatment process can rapidly produce important and variable impacts on DBP levels in water and air and suggests that implementation of any water treatment process to reduce DBP levels should take into account the specific context of each swimming pool.  相似文献   
23.
This paper sets out to describe the environmental impact assessment for wood charcoal briquettes produced from eucalyptus wood in Brazil, with specific reference to those impacts associated with Global Warming Potential. To achieve that objective, the work was undertaken in accordance with ISO 14040 "Environmental management - Life cycle assessment - Principles and framework" which describes essential LCA characteristics and good practices. Charcoal briquettes are produced from two basic raw materials, charcoal fines and starch. The fines result from the production of charcoal from sustainably managed eucalyptus plantations. Starch is extracted from babaçu pulp in the Amazon region. Multi-output processes were allocated based on income from the different by-products. The results showed that more than 90% of incoming CO2 was due to biomass production for charcoal, and the remainder to starch biomass production. Based on Brazilian data, as well as information provided by the GaBi4.3 database, it turned out that supplying the energy content of 1 kg of briquettes resulted in the sequestration of 3.9690 kg of CO2, i.e. around 4 kg of CO2 per kg of briquettes produced. CO2 emissions throughout the briquette production process are totally compensated for by the environmental quality of the raw materials used.  相似文献   
24.
A simplified means of probabilistic risk assessment (PRA) for long-range atmospheric transport based on a K-diffusion model is presented. In a case study, model parameters are estimated by comparing with the results of long-range atmospheric dispersion model calculations using one-year numerical weather prediction model data. It is found that the estimated ensemble mean provides a reasonable first approximation to the total dry and wet deposition from the one-year continuous release.  相似文献   
25.
Wulff F  Savchuk OP  Sokolov A  Humborg C  Mörth CM 《Ambio》2007,36(2-3):243-249
We are using the coupled models in a decision support system, Nest, to evaluate the response of the marine ecosystem to changes in external loads through various management options. The models address all the seven major marine basins and the entire drainage basin of the Baltic Sea. A series of future scenarios have been developed, in close collaboration with the Helsinki Commission, to see the possible effects of improved wastewater treatment and manure handling, phosphorus-free detergents, and less intensive land use and live stocks. Improved wastewater treatment and the use of phosphorus-free detergents in the entire region would drastically decrease phosphorus loads and improve the marine environment, particularly the occurrence of cyanobacterial blooms. However, the Baltic Sea will remain eutrophic, and to reduce other effects, a substantial reduction of nitrogen emissions must be implemented. This can only be obtained in these scenarios by drastically changing land use. In a final scenario, we have turned 50% of all agricultural lands into grasslands, together with efficient wastewater treatments and a ban of phosphorus in detergents. This scenario will substantially reduce primary production and the extension of hypoxic bottoms, increase water transparency in the most eutrophied basins, and virtually eliminate extensive cyanobacterial blooms.  相似文献   
26.
Urinary copper (Cu), nickel (Ni) and cobalt (Co) concentrations were determined for 127 Cu refinery workers (40 females, 87 males), with values of the 95% upper confidence interval of the geometric mean in nmol per mmol creatinine of 89 (Ni), 42 (Cu) and 3.4 (Co) for electrorefinery workers. In the pyrometallurgical departments, the corresponding concentrations were 37 (Ni), 99 (Cu) and 11 (Co). Female workers had higher Co urinary concentrations than males (p< or = 0.05) while no gender difference was observed for Cu and Ni. Inter-elemental correlations were moderate to weak. Based on the inhalable aerosol levels reported previously for the same workers, the observed urinary Cu concentrations were considerably lower than expected, relative to Co and Ni. This is interpreted in terms of the current understanding of Cu homeostasis.  相似文献   
27.
The growing recognition that climate change mitigation alone will be inadequate has led scientists and policymakers to discuss climate geoengineering. An experiment with a US sample found, contrary to previous research, that reading about geoengineering did not reduce conservatives’ skepticism about the existence of anthropogenic climate change. Moreover, depending on how it is framed, geoengineering can reduce support for mitigation among both conservatives and non-conservatives. When geoengineering is framed as a major solution, people worry less about climate change, leading to reduced mitigation support. When framed as disastrous, people perceived geoengineering as riskier, also leading to a decrease in mitigation support. A more moderate framing of geoengineering as a partial solution is less susceptible to moral hazard effects. Overall, results suggest that geoengineering will not lessen political polarization over anthropogenic climate change, and could undercut support for mitigation efforts. Instead, framing geoengineering as a small piece to solving a big puzzle seems to be the best strategy to weaken this potential moral hazard.  相似文献   
28.
Management of water quality in drinking water catchments is of ongoing, high importance as nitrate concentrations are often still very high. We analysed the Augsburg catchment in Germany, a unique example where a result-oriented approach has been implemented. We investigated the historical evolution of the water protection programme, the result-oriented payment contracts with farmers, and farmer satisfaction with the contracts, based on interviews with the water utility and farmers as well as an analysis of the literature. Today, the water protection programme has been successfully implemented, and a significant reduction of nitrate concentration was achieved due to the following factors: (1) investment of non-negligible amounts of money for high compensation and remuneration payments, (2) different contract options, (3) farmers’ participation in the negotiation process for result-oriented payment contracts, (4) involvement of “outside” people and institutions in negotiation processes, (5) anticipation of starting a programme when nitrate levels were still far below legislative thresholds, and (6) a political and legislative framework allowing direct decisions by a water supplier.  相似文献   
29.
While methodological choices are critical for solution-oriented adaptation research, the current debate on these is underdeveloped and characterized by simple dichotomies such as bottom-up and top-down as well as vaguely defined concepts such as vulnerability. Adaptation challenges and approaches for addressing them are more diverse than these labels suggest. This paper addresses this deficit by developing a diagnostic framework that helps to identify approaches suitable for addressing a given adaptation challenge. The framework was developed out of the necessity to discuss diverse approaches from natural science, social science and practice in a set of adaptation case studies conducted within the European funded MEDIATION project. Based on these case studies complemented by the literature, we iteratively abstracted typical adaptation challenges researched, typical approaches taken, and empirical, theoretical and normative criteria applied for choosing a particular approach. Our results refine the methodological debate by distinguishing between the three general adaptation challenges of identifying adaptation needs, identifying adaptation measures and appraising adaptation options. Adaptation challenges are further classified according to private and public interest involved, individual or various types of collective action involved, data/model availability, decision-making time horizon, etc. For each type of challenge and approach, we give examples and discuss salient issues. Our results point to the opportunity to apply institutional and behavioural research to support the identification of measures and possibly avoiding barriers in practice. The diagnostic framework also serves as the basis for the forthcoming guidance for assessing vulnerability, impacts and adaptation to be published by the UNEP programme of research on climate change vulnerability, impacts and adaptation.  相似文献   
30.
Journal of Material Cycles and Waste Management - The daily use of facemask to prevent virus transmission increases the negative effect on the environment because of improper waste disposal. Due to...  相似文献   
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