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311.
Initiatives to reduce community carbon emissions and foster sustainable lifestyles have had varying degrees of success. There is now a need for a re-energised, concerted and joined-up approach that places environmental issues in a wider context – one that improves quality of life while building community resilience. This involves enhancing the capacity of neighbourhoods to recover, respond and adapt to environmental and socio-economic changes. This paper examines the experience gained in a participatory action research (PAR) study to build community resilience, where facilitators supported residents to take ownership of their own agendas. The New Earswick Good Life Initiative (GLI) was an 18-month project undertaken in a low-income suburb of York (UK). A range of approaches were used to identify activities which had the most potential to nurture resilience and foster a shift towards greater environmental sustainability. The GLI highlighted how the introduction of new ideas not only need to be locally relevant but also requires care and time in order for them to embed within community. Altering the way a community manages its environment involves transforming social relationships, strengthening institutions and influencing local power balances. Furthermore, it is necessary to build social capital, knowledge, leadership skills and support social networks to allow communities to effectively engage with relevant local and national policies. Only by providing opportunities to develop these resilient attributes can increased local responsibility be successful. The paper concludes by providing guidance on strengthening community resilience and delivering pro-environmental behaviour change.  相似文献   
312.
Closing Remarks     
Considerable attention has been paid in recent years to photochemical smog pollution close to the earth's surface and to stratospheric ozone depletion. There is reason to suspect that the next round of scientific concern will be devoted to the perturbations in the “free troposphere.” Tropospheric ozone has been building up in many regions of the northern hemisphere. Ozone changes in the upper troposphere will exert a considerable impact on global warming. This could affect moisture levels, cloud amount and distribution, precipitation, and atmospheric dynamics on different scales.

This paper analyzes: (1) the physical and chemical processes contributing to changes in tropospheric ozone concentration; (2) the observational evidence of previous ozone change; and (3) results drawn from computer modelling of past and future radiative forcing caused by rising ozone concentrations in the upper troposphere.

The solar and longwave radiative model developed by Wang et al. (1991) was used for calculating the change in radiative forcing to the troposphere-surface system that can be ascribed to changing concentrations in ozone and other greenhouse gases. Nitric oxide emission from aircraft are a prime suspect for the observed increases in upper tropospheric ozone. The inference can be drawn that a radiative forcing of 0.2 to 0.35 Wm-2 will result from a doubling of aircraft emissions over the next two decades. This will amount to 10 to 25 percent of the radiative forcing attributable to CO2 alone for the same period. The effect of doubling aircraft emissions will increase as stratospheric ozone concentrations recover from the recent buildup of harmful chlorofluorocarbons. A large fraction of the radiative forcing that occurred during the 1970 to 1990 period can be attributed to increases in tropospheric ozone as opposed to increases in other greenhouse gases.  相似文献   
313.
In an era when the cost of compliance with state and federal environmental laws is rapidly rising, sometimes entities, such as operators of waste sites, are unable to pay these and other operating costs and are forced to file for bankruptcy. Citing Midlantic Nat'l Bank v. N.J. Dep't of Envtl. Protection and state environmental laws, bankruptcy trustees may be suing PRPs in bankruptcy courts to share the costs to clean up debtors' waste sites. This article suggests strategies by which PRPs can avoid litigating such lawsuits in the bankruptcy courts and instead resolve them before state and/or federal forums—where they properly belong.  相似文献   
314.
ABSTRACT

Solid phase microextraction (SPME) presents many advantages over conventional analytical methods by combining sampling, preconcentration, and direct transfer of the analytes into a standard gas chromatograph (GC). Since its commercial introduction in the early 1990s, SPME has been successfully applied to the sampling and analysis of environmental samples. This paper presents an overview of the current methods for air sampling and analysis with SPME using both grab and time-weighted average (TWA) modes. Methods include total volatile organic compounds (TVOCs), formaldehyde, and several target volatile organic compounds (VOCs). Field sampling data obtained with these methods in indoor air were validated with conventional methods based on sorbent tubes. The advantages and challenges associated with SPME for air sampling are also discussed. SPME is accurate, fast, sensitive, versatile, and cost-efficient, and could serve as a powerful alternative to conventional methods used by the research, industrial, regulatory, and academic communities.  相似文献   
315.
316.
Quantification of leaks from natural gas (NG) infrastructure is a key step in reducing emissions of the greenhouse gas methane (CH4), particularly as NG becomes a larger component of domestic energy supply. The U.S. Environmental Protection Agency (EPA) requires measurement and reporting of emissions of CH4 from NG transmission, storage, and processing facilities, and the high-flow sampler (or high-volume sampler) is one of the tools approved for this by the EPA. The Bacharach Hi-Flow Sampler (BHFS) is the only commercially available high-flow instrument, and it is also used throughout the NG supply chain for directed inspection and maintenance, emission factor development, and greenhouse gas reduction programs. Here we document failure of the BHFS to transition from a catalytic oxidation sensor used to measure low NG (~5% or less) concentrations to a thermal conductivity sensor for higher concentrations (from ~5% to 100%), resulting in underestimation of NG emission rates. Our analysis includes both our own field testing and analysis of data from two other studies (Modrak et al., 2012; City of Fort Worth, 2011). Although this failure is not completely understood, and although we do not know if all BHFS models are similarly affected, sensor transition failure has been observed under one or more of these conditions: (1) Calibration is more than ~2 weeks old; (2) firmware is out of date; or (3) the composition of the NG source is less than ~91% CH4. The extent to which this issue has affected recent emission studies is uncertain, but the analysis presented here suggests that the problem could be widespread. Furthermore, it is critical that this problem be resolved before the onset of regulations on CH4 emissions from the oil and gas industry, as the BHFS is a popular instrument for these measurements.

Implications: An instrument commonly used to measure leaks in natural gas infrastructure has a critical sensor transition failure issue that results in underestimation of leaks, with implications for greenhouse gas emissions estimates as well as safety.  相似文献   
317.
The purpose of this study was to examine the kinetics and equilibrium properties of freshwater algae with Cu2+. This was a model system to explore using algae as biosensors for water quality. Methods included making luminescence measurements (fluorescence) and copper ion-selective electrode (CuISE) measurements vs. time to obtain kinetic data. Results were analyzed using a pseudo-first-order model to calculate the rate constants of Cu2+ uptake by algae: k p(Cu?Calgae)?=?0.0025?±?0.0006?s?1 by CuISE and k p(Cu?Calgae)?=?0.0034?±?0.0011?s?1 by luminescence. The binding constant of Cu?Calgae, K Cu?Calgae, was 1.62?±?0.07?×?107?M?1. Fluorescence results analyzed using the Stern?CVolmer relationship indicate that algae have two types of binding sites of which only one appears to affect quenching. The fluorescence-based method was found to be able to detect the reaction of algae with Cu2+ quickly and at a detection limit of 0.1?mg?L?1.  相似文献   
318.
An urban soil chronosequence in downtown Detroit, MI was studied to determine the effects of time on pedogenesis and heavy metal sequestration. The soils developed in fill derived from mixed sandy and clayey diamicton parent materials on a level late Pleistocene lakebed plain under grass vegetation in a humid-temperate (mesic) climate. The chronosequence is comprised of soils in vacant lots (12 and 44 years old) and parks (96 and 120 years old), all located within 100 m of a roadway. An A-horizon 16 cm thick with 2% organic matter has developed after only 12 years of pedogenesis. The 12 year-old soil shows accelerated weathering of iron (e.g. nails) and cement artifacts attributed to corrosion by excess soluble salts of uncertain origin. Carbonate and Fe-oxide are immobilizing agents for heavy metals, hence it is recommended that drywall, plaster, cement and iron artifacts be left in soils at brownfield sites for their ameliorating effects.  相似文献   
319.
Open Air Laboratories (OPAL): a community-driven research programme   总被引:1,自引:0,他引:1  
OPAL is an English national programme that takes scientists into the community to investigate environmental issues. Biological monitoring plays a pivotal role covering topics of: i) soil and earthworms; ii) air, lichens and tar spot on sycamore; iii) water and aquatic invertebrates; iv) biodiversity and hedgerows; v) climate, clouds and thermal comfort. Each survey has been developed by an inter-disciplinary team and tested by voluntary, statutory and community sectors. Data are submitted via the web and instantly mapped. Preliminary results are presented, together with a discussion on data quality and uncertainty. Communities also investigate local pollution issues, ranging from nitrogen deposition on heathlands to traffic emissions on roadside vegetation. Over 200,000 people have participated so far, including over 1000 schools and 1000 voluntary groups. Benefits include a substantial, growing database on biodiversity and habitat condition, much from previously unsampled sites particularly in urban areas, and a more engaged public.  相似文献   
320.
The feasibility of reducing children's exposure to lead (Pb) polluted soil in New Orleans is tested. Childcare centers (median = 48 children) are often located in former residences. The extent of soil Pb was determined by selecting centers in both the core and outlying areas. The initial 558 mg/kg median soil Pb (range 14-3692 mg/kg) decreased to median 4.1 mg/kg (range 2.2-26.1 mg/kg) after intervention with geotextile covered by 15 cm of river alluvium. Pb loading decreased from a median of 4887 μg/m(2) (454 μg/ft(2)) range 603-56650 μg/m(2) (56-5263 μg/ft(2)) to a median of 398 μg/m(2) (37 μg/ft(2)) range 86-980 μg/m(2) (8-91 μg/ft(2)). Multi-Response Permutation Procedures indicate similar (P-values = 0.160-0.231) soil Pb at childcare centers compared to soil Pb of nearby residential communities. At ~$100 per child, soil Pb and surface loading were reduced within hours, advancing an upstream intervention conceptualization about Pb exposure prevention.  相似文献   
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