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51.
Network-bound systems such as water and energy systems are increasingly confronted with environmental problems that cannot be solved without changing their modes of provision. More than any other flow provided through a network-bound system, the waste water flow comes very close to intimate personal and social life, complicating the introduction of environmental innovations in this sector. Using the concepts of trust and identity, questions concerning changing consumer roles in two cases of Decentralised Sanitation and Reuse Systems in the Netherlands are addressed. In both cases the building of trust within provider networks and between consumers and providers, as well as the possibility for consumers and providers to identify themselves with the aims of the project were key factors determining the success or failure of environmental innovations in waste water flows.  相似文献   
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Problem and objective

The translation of the evidence-base for preventing falls among community-dwelling older people into practice has been limited. This study systematically reviewed and synthesised the effectiveness of methods to implement falls prevention programmes with this population.

Methods

Articles published between 1980 and May 2010 that evaluated the effects of an implementation strategy. No design restrictions were imposed. A narrative synthesis was undertaken.

Results

15 studies were identified. Interventions that involved the active training of healthcare professionals improved implementation. The evidence around changing the way people who fall are managed within primary care practices, and, layperson, peer or community delivered models was mixed.

Impact on industry

Translating the evidence-base into practice involves changing the attitudes and behaviours of older people, healthcare professionals and organisations. However, there is a need for further evaluation on how this can be best achieved.  相似文献   
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This study measures the impact of fanya juu terraces on the net value of crop income in a high‐rainfall area in the Ethiopian highlands using cross‐sectional multiple plot observations. Using propensity score matching methods we find that the net value of crop income for plots with fanya juu terraces is lower than for plots without fanya juu terraces. This finding makes it difficult to avoid concluding that while the technologies might reduce soil erosion and associated off‐site effects, they do so at the expense of poor farmers in the Ethiopian highlands. Therefore, fanya juu terraces cannot be characterized as a “win‐win” measure to reduce soil erosion. New agricultural technologies need to be profitable to the farmer if they are to be adopted and sustained.  相似文献   
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Accurate quantification of stormwater pollutant levels is essential for estimating overall contaminant discharge to receiving waters. Numerous sampling approaches exist that attempt to balance accuracy against the costs associated with the sampling method. This study employs a novel and practical approach of evaluating the accuracy of different stormwater monitoring methodologies using stormflows and constituent concentrations produced by a fully validated continuous simulation watershed model. A major advantage of using a watershed model to simulate pollutant concentrations is that a large number of storms representing a broad range of conditions can be applied in testing the various sampling approaches. Seventy-eight distinct methodologies were evaluated by "virtual samplings" of 166 simulated storms of varying size, intensity and duration, representing 14 years of storms in Ballona Creek near Los Angeles, California. The 78 methods can be grouped into four general strategies: volume-paced compositing, time-paced compositing, pollutograph sampling, and microsampling. The performances of each sampling strategy was evaluated by comparing the (1) median relative error between the virtually sampled and the true modeled event mean concentration (EMC) of each storm (accuracy), (2) median absolute deviation about the median or "MAD" of the relative error or (precision), and (3) the percentage of storms where sampling methods were within 10% of the true EMC (combined measures of accuracy and precision). Finally, costs associated with site setup, sampling, and laboratory analysis were estimated for each method. Pollutograph sampling consistently outperformed the other three methods both in terms of accuracy and precision, but was the most costly method evaluated. Time-paced sampling consistently underestimated while volume-paced sampling over estimated the storm EMCs. Microsampling performance approached that of pollutograph sampling at a substantial cost savings. The most efficient method for routine stormwater monitoring in terms of a balance between performance and cost was volume-paced microsampling, with variable sample pacing to ensure that the entirety of the storm was captured. Pollutograph sampling is recommended if the data are to be used for detailed analysis of runoff dynamics.  相似文献   
55.
Recent conservation planning studies have presented approaches for integrating spatially referenced social (SRS) data with a view to improving the feasibility of conservation action. We reviewed the growing conservation literature on SRS data, focusing on elicited or stated preferences derived through social survey methods such as choice experiments and public participation geographic information systems. Elicited SRS data includes the spatial distribution of willingness to sell, willingness to pay, willingness to act, and assessments of social and cultural values. We developed a typology for assessing elicited SRS data uncertainty which describes how social survey uncertainty propagates when projected spatially and the importance of accounting for spatial uncertainty such as scale effects and data quality. These uncertainties will propagate when elicited SRS data is integrated with biophysical data for conservation planning and may have important consequences for assessing the feasibility of conservation actions. To explore this issue further, we conducted a systematic review of the elicited SRS data literature. We found that social survey uncertainty was commonly tested for, but that these uncertainties were ignored when projected spatially. Based on these results we developed a framework which will help researchers and practitioners estimate social survey uncertainty and use these quantitative estimates to systematically address uncertainty within an analysis. This is important when using SRS data in conservation applications because decisions need to be made irrespective of data quality and well characterized uncertainty can be incorporated into decision theoretic approaches.  相似文献   
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The Federal role in the enforcement of water quality requirements is of recent development. It began with the enactment in 1956 of the Federal Water Pollution Control Act as permanent law. It has been expanded by successive amendments to the Act to cover the pollution of navigable as well as interstate waters which endangers the health or welfare of persons, and to cover violations of water quality standards established for interstate waters. Two different enforcement procedures are prescribed in the law to be followed in the two types of enforcement actions. While questions have arisen of jurisdiction, States' rights, and disregard or duplication of local efforts, such questions do not lastingly impede the exercise of Federal enforcement authority and are of value in establishing a body of precedents. Limitations have their basis in the statutory distinctions between interstate and intrastate pollution which govern the application of the enforcement authority, even though a case of intrastate pollution may be as serious or more serious than a case of interstate pollution. An additional limitation results from the statutory time intervals between procedural stages in an action. Lack of data is a limitation but can always be overcome and at most causes delay. State laws which protect the confidentiality of required reports are more of a limitation. Investigative teams may obtain the needed information, however, for consideration in public meetings. Public support for effective water quality control measures, especially enforcement, and for the expenditures needed to enhance the environment, is widespread. Such support may be instrumental in modifying or eliminating existing statutory limitations.  相似文献   
58.
Constructed wetlands are widely used for wastewater treatment, but there is little information on processes affecting their performance in cold climates, effects of plants on seasonal performance, or plant selection for cold regions. We evaluated the effects of three plant species on seasonal removal of dissolved organic matter (OM) (measured by chemical oxygen demand and dissolved organic carbon) and root zone oxidation status (measured by redox potential [Eh] and sulfate [SO4(2-)]) in subsurface-flow wetland (SSW) microcosms. A series of 20-d incubations of simulated wastewater was conducted during a 28-mo greenhouse study at temperatures from 4 to 24 degrees C. Presence and species of plants strongly affected seasonal differences in OM removal and root zone oxidation. All plants enhanced OM removal compared with unplanted controls, but plant effects and differences among species were much greater at 4 degrees C, during dormancy, than at 24 degrees C, during the growing season. Low temperatures were associated with decreased OM removal in unplanted controls and broadleaf cattail (Typha latifolia L.) microcosms and with increased removal in beaked sedge (Carex rostrata Stokes) and hardstem bulrush [Schoenoplectus acutus (Muhl. ex Bigelow) A. & D. L?ve var. acutus] microcosms. Differences in OM removal corresponded to species' apparent abilities to increase root zone oxygen supply. Sedge and bulrush significantly raised Eh values and SO4(2-) concentrations, particularly at 4 degrees C. These results add to evidence that SSWs can be effective in cold climates and suggest that plant species selection may be especially important to optimizing SSW performance in cold climates.  相似文献   
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