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111.
Jon Birger Skjærseth 《环境政策》2018,27(3):498-518
European Union (EU) climate/energy targets and policies are poised for the first full climate policy cycle – from adoption and implementation of the policy package for 2020, to reform for 2030. A dynamic approach to the ways in which EU policies affect policy development is developed by applying theories of domestic implementation, policy feedback and integration. Implementation experiences in Poland – the ‘least climate ambitious’ EU member state – affected Polish preferences for reformed EU policies. Existing EU policies, their ‘fit’ with Poland’s energy interests and change in anticipation of future EU policies explain much of the variation in preferences. Second, policy feedback from Poland significantly affected the EU 2030 climate and energy framework. As yet, the EU has succeeded only partly in gathering momentum through a ‘snowball’ effect whereby positive policy feedback from implementation generates further steps. 相似文献
112.
Christine L. Goldstein Karl W.J. Williard Jon E. Schoonover 《Journal of the American Water Resources Association》2009,45(3):664-672
Abstract: Autumn‐olive (Elaeagnus umbellata Thunb.) is an invasive, exotic shrub that has become naturalized in the eastern United States. Autumn‐olive fixes nitrogen (N) via a symbiotic relationship with the actinomycete Frankia. At the plot scale, the presence of autumn‐olive has been related to elevated soil water nitrate‐N (NO3?‐N) concentrations. This study examined the relationship between autumn‐olive cover in a watershed and stream water quality. Stream water nitrate‐N (NO3?‐N) and ammonium‐N (NH4+‐N) concentrations were measured in 12 first order ephemeral streams draining watersheds with mixed forest cover and a range of 0‐35% autumn‐olive cover. Percent autumn‐olive cover was positively correlated with mean stream NO3?‐N concentrations, but was not correlated with mean stream NH4+‐N concentrations. While other studies have demonstrated a significant relationship between native N‐fixers and stream NO3?‐N, this is the first study to document a relationship for an invasive, exotic N‐fixing species. Results suggest that this exotic species can be an additional source of NO3? in local and regional water bodies and demonstrates an additional negative ecosystem consequence of invasion beyond losses in biodiversity. 相似文献
113.
William M. Cox Jon Clark 《Journal of the Air & Waste Management Association (1995)》2013,63(7):762-766
Data on dally maximum ozone concentrations measured at ambient air monitoring stations operated by state and local air pollution control agencies in the Eastern United States were analyzed using principal factor analysis. Four orthogonal factors representing O3 formation potentials were derived using the statistical package SPSS; these factors accounted for over two-thirds of the variations in 1978 summer O3 levels at 21 urban-oriented stations. The analysis confirmed that O3 variations are similar among stations within defined geographical areas; this confirmation supports the widely held theory that ambient O3 formations are reglonwlde. The analysis suggested that trends analysis for determining general progress in improving O3 air quality should be based on aggregate statistics from clusters of monitors rather than from a single monitoring station within areas associated with the derived factors. 相似文献
114.
Jon M. Heuss 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1152-1153
Abstract A mathematical model is proposed for assessing health risk rates of fluctuating concentrations. Each time-averaged concentration may be regarded as a dose that, when applied to the dose-response curve, produces a risk of an adverse effect. A theoretical derivation shows that the dose-response pattern is a cumulative lognormal curve because of the diversity of the individuals in the exposed population. Similarly, the concentration pattern is a log-normal distribution because of the diversity of emission sources and dispersive processes. The health risk is produced by the overlapping of the right tail of the concentration distribution and the left tail of the dose-response curve. The evaluation of the joint probability in this region has been performed by numerical integration by computer in terms of two generalized parameters. One represents the geometric standard deviation of the concentration distribution relative to that of the dose-response curve, and the other represents the distance between the geometric mean concentration and the concentration producing an adverse response in 50% of the exposed population. These results are presented graphically and in tabular form. If the two parameters of the dose-response curve are known, the health risk of the concentration pattern may be calculated conveniently for any geometric mean and geometric standard deviation values. 相似文献
115.
Jon B. Manchester-Neesvig Glen R. Cass 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1065-1079
Abstract Atmospheric particulate matter (PM) samples from 12 sites in southern California, collected as part of the Southern California Children’s Health Study (SCCHS), were analyzed using gas chromatography/mass spectrometry (GC/MS) techniques. Ninety-four organic compounds were quantified in these samples, including n-alkanes, fatty acids, polycyclic aromatic hydrocarbons (PAH), ho-panes, steranes, aromatic diacids, aliphatic diacids, resin acids, methoxyphenols, and levoglucosan. Annual average concentrations of all detected compounds, as well as average concentrations for three seasonal periods, were determined at all 12 sites for the calendar year of 1995. These measurements provide important information about the seasonal and spatial distribution of particle-phase organic compounds in southern California. Also, co-located samples from one site were analyzed to assess precision of measurement. Excellent agreement was observed between annual average concentrations for the broad range of organic compounds measured in this study. Measured concentrations from the 12 sampling sites were used in a previously developed molecular-marker source apportionment model to quantify the primary source contributions to the PM10 organic carbon and mass concentrations at these 12 sites. Source contributions to atmospheric PM from six important air pollution sources were quantified: gasoline-powered motor vehicle exhaust, diesel vehicle exhaust, wood smoke, vegetative detritus, tire wear, and natural gas combustion. Important trends in the seasonal and spatial patterns of the impact of these six sources were observed. In addition, contributions from meat smoke were detected in selected samples. 相似文献
116.
Jon Leonard R. Del Delumyea 《Journal of the Air & Waste Management Association (1995)》2013,63(6):804-806
Elemental carbon (EC) particles have been found in the lungs of dolphins. The question arose as to whether these particles originated over land or water. This project determined the amount of EC particulate found in terrestrial air. Portions of paniculate filters and associated data collected during the period from January 1990 through December 1991 were provided by the Florida Department of Environmental Regulation. Using reflectance spectroscopy and laboratory-generated standards, atmospheric concentrations of EC and TSP were determined. This paper addresses the data from those counties which surround Tampa Bay. In the spring of 1992, a television news station reported that researchers at Mote Marine Institute had found black carbon particulates in the lungs of dolphins (reported as “...dolphins with Black Lung Disease..."). The dolphins were found in the Gulf of Mexico off the coast of Florida.1 In discussions with a principal investigator of the dolphin study, the question arose as to whether these particulates came from urban or marine sources. No comprehensive investigation of soot concentrations in the air over Florida had been made. This study reports the elemental carbon (EC) content of urban particulate matter in the Tampa Bay region, where the affected dolphins were discovered between 1988 and 1990 (Sarasota County). This is the first step toward answering whether urban concentrations of EC were sufficient to contribute measurably to the EC found in the marine environment. Future efforts will address marine concentrations and sources of EC. Elemental carbon, commonly termed “soot,” is a product of incomplete combustion. Common urban sources of EC in particulate matter include both mobile sources (diesel-powered buses, cars, and trucks) and point sources (incinerators, power plants and home heating units). The State of Florida operates environmental monitoring stations in selected municipalities around the state. At these stations, which were sited according to EPA requirements2, Total Suspended Particulate (TSP) samples were collected using the accepted methods.3 These samples were suitable for EC analysis. Samples collected in the Tampa Bay region in 199b and 1991 were analyzed for EC content using reflectance spectroscopy. EC concentrations were calculated in micrograms per cubic meter (μg/m3). 相似文献
117.
Jon Ivar Håvold 《Safety Science》2010,48(8):1054-1061
Safety at sea is a serious issue for the commercial fishing industry. Injury and fatality rates are between 25 and 40 times the national average in many European counties, Australia and the USA. A 50-item safety culture questionnaire was developed, using items from published research combined with some original items. The questionnaire was distributed to fishermen who completed the responses. A total of 209 questionnaires were collected. Principal Component Analysis (PCA) revealed nine factors, all with a Cronbach’s Alpha higher than 0.68. The factors were tested using ANOVA, t-tests, correlations and regression analysis.The findings indicate significant differences between age groups, vessel types, occupations, and whether or not a close family member is a fisherman. It was also found that the safety attitude of management had a strong influence on a company’s safety policy. Fishermen who had sought medical attention during the preceding year as a result of an accident showed a significantly less positive attitude to rules and regulations and had a less positive safety attitude in general. Fishermen who had been involved in a serious accident/incident showed a significantly more positive attitude to rules and regulations. 相似文献
118.
119.
Dr Jon Kellett 《Journal of Environmental Planning and Management》2007,50(3):381-396
Whilst the existence of global climate change is no longer seriously contested and most governments are seeking to adopt appropriate responses, the rate of engagement with these measures is slow. Top-down policies and reliance on market mechanisms are failing to produce the reductions in energy demand and shifts away from fossil fuel reliance that are required. This paper outlines an example of a research programme that seeks to deliver more rapid change. It focuses on the potential for carbon emission reduction in a deprived community in South Yorkshire, UK, and reports on an approach that could be replicated elsewhere. The method includes estimation of baseline energy demand, energy efficiency potential and renewable energy resource assessment as a precursor to action. An innovative community-based energy service company is described and the benefits of a community-based bottom-up approach to carbon reduction are outlined. 相似文献
120.
Scott V. Harder Devendra M. Amatya Timothy J. Callahan Carl C. Trettin Jon Hakkila 《Journal of the American Water Resources Association》2007,43(3):563-575
Abstract: Increases in timber demand and urban development in the Atlantic Coastal Plain over the past decade have motivated studies on the hydrology, water quality, and sustainable management of coastal plain watersheds. However, studies on baseline water budgets are limited for the low‐lying, forested watersheds of the Atlantic Coastal Plain. The purpose of this study was to document the hydrology and a method to quantify the water budget of a first‐order forested watershed, WS80, located within the USDA Forest Service Santee Experimental Forest northeast of Charleston, South Carolina. Annual Rainfall for the 2003 and 2004 periods were 1,671 mm (300 mm above normal) and 962 mm (over 400 mm below normal), respectively. Runoff coefficients (outflow as a fraction of total rainfall) for the 2003 and 2004 periods were 0.47 and 0.08, respectively, indicating a wide variability of outflows as affected by antecedent conditions. A spreadsheet‐based Thornthwaite monthly water balance model was tested on WS80 using three different potential evapotranspiration estimators [Hamon, Thornthwaite, and Penman‐Monteith (P‐M)]. The Hamon and P‐M‐based methods performed reasonably well with average absolute monthly deviations of 12.6 and 13.9 mm, respectively, between the measured and predicted outflows. Estimated closure errors were all within 9% for the 2003, 2004, and seasonal water budgets. These results may have implications on forest management practices and provide necessary baseline or reference information for Atlantic Coastal Plain watersheds. 相似文献