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861.
862.
Increasing urban water self-sufficiency: new era, new challenges 总被引:3,自引:0,他引:3
Urban water supplies are traditionally based on limited freshwater resources located outside the cities. However, a range of concepts and techniques to exploit alternative water resources has gained ground as water demands begin to exceed the freshwater available to cities. Based on 113 cases and 15 in-depth case studies, solutions used to increase water self-sufficiency in urban areas are analyzed. The main drivers for increased self-sufficiency were identified to be direct and indirect lack of water, constrained infrastructure, high quality water demands and commercial and institutional pressures. Case studies demonstrate increases in self-sufficiency ratios to as much as 80% with contributions from recycled water, seawater desalination and rainwater collection. The introduction of alternative water resources raises several challenges: energy requirements vary by more than a factor of ten amongst the alternative techniques, wastewater reclamation can lead to the appearance of trace contaminants in drinking water, and changes to the drinking water system can meet tough resistance from the public. Public water-supply managers aim to achieve a high level of reliability and stability. We conclude that despite the challenges, self-sufficiency concepts in combination with conventional water resources are already helping to reach this goal. 相似文献
863.
Didac Pascual Jonas kerman Marina Becher Terry V. Callaghan Torben R. Christensen Ellen Dorrepaal Urban Emanuelsson Reiner Giesler Dan Hammarlund Edward Hanna Annika Hofgaard Hongxiao Jin Cecilia Johansson Christer Jonasson Jonatan Klaminder Jan Karlsson Erik Lundin Anders Michelsen David Olefeldt Andreas Persson Gareth K. Phoenix Zofia Rczkowska Riikka Rinnan Lena Strm Jing Tang Ruth K. Varner Philip Wookey Margareta Johansson 《Ambio》2021,50(2):375
Arctic and subarctic ecosystems are experiencing substantial changes in hydrology, vegetation, permafrost conditions, and carbon cycling, in response to climatic change and other anthropogenic drivers, and these changes are likely to continue over this century. The total magnitude of these changes results from multiple interactions among these drivers. Field measurements can address the overall responses to different changing drivers, but are less capable of quantifying the interactions among them. Currently, a comprehensive assessment of the drivers of ecosystem changes, and the magnitude of their direct and indirect impacts on subarctic ecosystems, is missing. The Torneträsk area, in the Swedish subarctic, has an unrivalled history of environmental observation over 100 years, and is one of the most studied sites in the Arctic. In this study, we summarize and rank the drivers of ecosystem change in the Torneträsk area, and propose research priorities identified, by expert assessment, to improve predictions of ecosystem changes. The research priorities identified include understanding impacts on ecosystems brought on by altered frequency and intensity of winter warming events, evapotranspiration rates, rainfall, duration of snow cover and lake-ice, changed soil moisture, and droughts. This case study can help us understand the ongoing ecosystem changes occurring in the Torneträsk area, and contribute to improve predictions of future ecosystem changes at a larger scale. This understanding will provide the basis for the future mitigation and adaptation plans needed in a changing climate.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01381-1) contains supplementary material, which is available to authorized users. 相似文献
864.
David P. Gilkey Thomas J. Keefe Philip L. Bigelow Robin E. Herron Kirby Duvall Jacob E. Hautaluoma 《International journal of occupational safety and ergonomics》2013,19(3):305-321
Occupational low back pain (LBP) remains a leading safety and health challenge. This cross-sectional investigation measured the prevalence of LBP in residential carpenters and investigated ergonomic risk factors. Ninety-four carpenters were investigated for LBP presence and associated risk factors. Ten representative job-tasks were evaluated using the Ovako Working Posture Analysis System (OWAS) and ErgoMaster? 2D software to measure elements of posture, stress, and risk. Job-tasks were found to differ significantly for total lumbar compression and shear at peak loading (p < .001), ranging from 2 956 to 8 606 N and 802 to 1 974 N respectively. OWAS indicated that slight risk for injury was found in 10 job-tasks while distinct risk was found in 7 of the 10 job-tasks. Seven of the 10 job-tasks exceeded the National Institute for Occupational Safety and Health (NIOSH) action limit of 3 400 N for low back loading. The point prevalence for LBP was 14% while the annual prevalence was 38%. 相似文献
865.
George Doubleday Antonia Sebastian Tatyana Luttenschlager Philip B. Bedient 《Journal of the American Water Resources Association》2013,49(6):1444-1455
Low Impact Development (LID) is alternative design approach to land development that conserves and utilizes natural resources to minimize the potential negative environmental impacts of development, such as flooding. The Woodlands near Houston, Texas is one of the premier master‐planned communities in the United States. Unlike in a typical urban development where riparian corridors are often replaced with concrete channels, pervious surfaces, vegetation, and natural drainage pathways were preserved as much as possible during development. In addition, a number of detention ponds were strategically located to manage runoff on site. This article uses a unique distributed hydrologic model, Vflo?, combined with historical (1974) and recent (2008 and 2009) rainfall events to evaluate the long‐term effectiveness of The Woodlands natural drainage design as a stormwater management technique. This study analyzed the influence of LID in The Woodlands by comparing the hydrologic response of the watershed under undeveloped, developed, and highly urbanized conditions. The results show that The Woodlands drainage design successfully reflects predeveloped hydrologic conditions and produces peak flows two to three times lower than highly urbanized development. Furthermore, results indicate that the LID practices employed in The Woodlands successfully attenuate the peak flow from a 100‐year design event, resulting in flows comparable to undeveloped hydrologic conditions. 相似文献
866.
Philip Ireland 《Local Environment》2013,18(2):187-201
This paper explores community perspectives of environmental change and the role development actors in the regional Nepali town of Nepalganj. Understanding these perceptions is crucial for planning future adaptation to climate change and ensuring that these measures are sustainable and in line with community priorities. Firstly, I contend that whilst the local community in Nepalganj may be experiencing the impacts of climate change, they are unfamiliar and disassociated with the concept. Secondly, I identify a number of risks and opportunities around the role of local government, international development organisations and local non-government organisations in future adaptation actions. Participant perceptions of these institutions in their community reinforce a number of established critiques of development around themes such as poor consultation and short project timelines. The long-term success of adaptation actions will be shaped by the ability and willingness of development actors to evolve their practices by listening to local communities. 相似文献
867.
On the value of temporary carbon: a comment on Kirschbaum 总被引:1,自引:1,他引:0
Philip M. Fearnside 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):207-210
A recent paper by Miko Kirschbaum (Mitigat Adapt Strategies Glob Change 11(5–6):1151–1164, 2006) argues that temporary carbon (C) storage has “virtually no climate-change mitigation value.” However, temporary carbon has
value in delaying global warming that needs to be recognized in carbon accounting methodologies. The conclusions reached are
very sensitive to any value that is attached to time. Basing analysis exclusively on the maximum temperature reached within
a 100-year time frame ignores other important impacts of global warming that also need to be included when mitigation strategies
are assessed. The relative weightings for long-term versus short-term impacts represent policy choices that result in a greater
or a lesser value being attributed to temporary carbon, but that value should not be zero. Global warming is too formidable
an enemy to allow us the luxury of discarding part of our arsenal in fighting against it. Both reducing fossil-fuel combustion
and increasing biosphere carbon stocks are needed. 相似文献
868.
AL-wesabi Ibrahim Zhijian Fang Bosah Chukwunonso Philip Dong Hanlin 《Environmental science and pollution research international》2022,29(36):53907-53933
Environmental Science and Pollution Research - 相似文献
869.
Benjamin K. Jessup Philip R. Kaufmann Forrest John Lynette S. Guevara Seva Joseph 《Journal of the American Water Resources Association》2014,50(6):1558-1574
Excess fine sediments in streambeds are among the most pervasive causes of degradation in streams of the United States. Simple criteria for acceptable streambed fines are elusive because streambed fines and biotic tolerances vary widely in the absence of human disturbances. In response to the need for sediment benchmarks that are protective of minimum aquatic life uses under the Clean Water Act, we undertook a case study using surveys of sediment, physical habitat, and macroinvertebrates from New Mexico streams. Our approach uses weight of evidence to develop suggested benchmarks for protective levels of surficial bedded sediments <0.06 mm (silt and finer) and <2.0 mm (sand and finer). We grouped streams into three ecoregions that were expected to produce similar naturally occurring streambed textures and patterns of response to human disturbances. Within ecoregions, we employed stressor response models to estimate fine sediment percentages and bed stability that are tolerated by resident macroinvertebrates. We then compared individual stream sediment data with distributions among least‐disturbed reference sites to determine deviation from natural conditions, accounting for natural variability across ecoregion, gradient, and drainage area. This approach for developing benchmark values could be applied more widely to provide a solid basis for developing bedded sediment criteria and other protective management strategies in other regions. 相似文献
870.
Brazil’s Cuiabá- Santarém (BR-163) Highway: The Environmental Cost of Paving a Soybean Corridor Through the Amazon 总被引:1,自引:0,他引:1
Fearnside PM 《Environmental management》2007,39(5):601-614
Brazil’s Cuiabá-Santarém (BR-163) Highway provides a valuable example of ways in which decision-making procedures for infrastructure
projects in tropical forest areas need to be reformulated in order to guarantee that environmental concerns are properly weighed.
BR-163, which is slated to be paved as an export corridor for soybeans via the Amazon River, traverses an area that is largely
outside of Brazilian government control. A climate of generalized lawlessness and impunity prevails, and matters related to
environment and to land tenure are especially unregulated. Deforestation and illegal logging have accelerated in anticipation
of highway paving. Paving would further speed forest loss in the area, as well as stimulate migration of land thieves (grileiros) to other frontiers. An argument is made that the highway should not be reconstructed and paved until after a state of law
has been established and it has been independently certified that sufficient governance prevails to secure protected areas
and enforce environmental legislation. A waiting period is needed after this is achieved before proceeding with the highway
paving. Above all, the logical sequence of steps must be followed, whereby environmental costs are assessed, reported, and
weighed prior to making de facto decisions on implementation of infrastructure projects. Deviation from this logical sequence is a common occurrence in many
parts of the world, especially in tropical areas. 相似文献