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21.
We are pleased to introduce this second issue of the Reviewof Environmental Economics and Policy. Like every issue, thisone includes several articles, a focused symposium, and a setof regular features. In the first of three articles, John Graham describes "The EvolvingRegulatory Role of the U.S. Office of Management and Budget,"where he was the "regulatory czar" as administrator of the Officeof Information and Regulatory Affairs (OIRA) from 2001 to 2006.In his essay, Graham responds to the perception of OMB as antiregulatoryby describing the history of OIRA's proactive  相似文献   
22.
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   
23.
The goal of the regional haze mitigation program in the United States is to attain "natural conditions" in national parks and wilderness areas by 2064. Results of research investigations on background concentrations of sea salt and biogenic organic matter, of episodic Saharan and Asian dust, and of carbon from natural fires were reviewed to provide a basis for making site-specific estimates of what the concentrations of atmospheric fine particulate matter components might be under natural conditions in the Southeastern United States. Based on this review, rough estimates were made of potential contributions of these aerosol components to natural background visibility. Natural organic particles were the dominant influence on the rate of visibility improvement required to reach natural conditions at an inland, mountainous location, and organic particles and sea salt were the dominant influences on the rate at a coastal location. African dust also had a large episodic effect, but the current regulatory approach is not designed to address episodic background variations. Insufficient data exist to quantify the contributions of wildfires with any detail, although global air pollution modeling provides insight, and their emissions can be locally dominant. Conservative regional refinements to the default natural background estimates do not greatly alter the region-wide rates of reduction of ambient particulate matter concentrations that will be needed to accomplish the first phase of the regional haze program. However, refinements at specific Class I areas may have considerable influence on defining the nature (magnitude and spatial and temporal distribution) of local emission reduction efforts there.  相似文献   
24.
ABSTRACT

The issue of fine particle (PM25) exposures and their potential health effects is a focus of scientific research because of the recently promulgated National Ambient Air Quality Standard for PM2 5. Before final implementation, the health and exposure basis for the standard will be reviewed by the U.S. Environmental Protection Agency within the next five years. As part of this process, it is necessary to understand total particle exposure issues and to determine the relative importance of the origin of PM2 5 exposure in various micro-environments. The results presented in this study examine emissions of fine particles from a previously uncharacterized indoor source: the residential vacuum cleaner. Eleven standard vacuum cleaners were tested for the emission rate of fine particles by their individual motors and for their efficiency in collecting laboratory-generated fine particles. An aerosol generator was used to introduce fine potassium chloride (KC1) particles into the vacuum cleaner inlet for the collection efficiency tests. Measurements of the motor emissions, which include carbon, and the KCl aerosol were made using a continuous HIAC/Royco 5130A light-scattering particle detector. All tests were conducted in a metal chamber specifically designed to completely contain the vacuum cleaner and operate it in a stationary position. For the tested vacuum cleaners, fine particle motor emissions ranged from 9.6 x 104 to 3.34 x 108 particles/min, which were estimated to be 0.028 to 176 mg/min for mass emissions, respectively. The vast majority of particles released were in the range of 0.3-0.5 mm in diameter. The lowest particle emission rate was obtained for a vacuum cleaner that had a high efficiency (HEPA) filter placed after the vacuum cleaner bag and the motor within a sealed exhaust system. This vacuum cleaner removed the KC1particles that escaped the vacuum cleaner bag and the particles emitted by the motor. Results obtained for the KC1 collection efficiency tests show >99% of the fine particles were captured by the two vacuum cleaners that used a HEPA filter. A series of tests conducted on two vacuum cleaners found that the motors also emitted ultra-fine particles above 0.01 mm in diameter at rates of greater than 108 ultra-fine particles/CF of air. The model that had the best collection efficiency for fine particles also reduced the ultra-fine particle emissions by a factor of 1 x 103.  相似文献   
25.
Emissions of exhaust gases and particles from oceangoing ships are a significant and growing contributor to the total emissions from the transportation sector. We present an assessment of the contribution of gaseous and particulate emissions from oceangoing shipping to anthropogenic emissions and air quality. We also assess the degradation in human health and climate change created by these emissions. Regulating ship emissions requires comprehensive knowledge of current fuel consumption and emissions, understanding of their impact on atmospheric composition and climate, and projections of potential future evolutions and mitigation options. Nearly 70% of ship emissions occur within 400 km of coastlines, causing air quality problems through the formation of ground-level ozone, sulphur emissions and particulate matter in coastal areas and harbours with heavy traffic. Furthermore, ozone and aerosol precursor emissions as well as their derivative species from ships may be transported in the atmosphere over several hundreds of kilometres, and thus contribute to air quality problems further inland, even though they are emitted at sea. In addition, ship emissions impact climate. Recent studies indicate that the cooling due to altered clouds far outweighs the warming effects from greenhouse gases such as carbon dioxide (CO2) or ozone from shipping, overall causing a negative present-day radiative forcing (RF). Current efforts to reduce sulphur and other pollutants from shipping may modify this. However, given the short residence time of sulphate compared to CO2, the climate response from sulphate is of the order decades while that of CO2 is centuries. The climatic trade-off between positive and negative radiative forcing is still a topic of scientific research, but from what is currently known, a simple cancellation of global mean forcing components is potentially inappropriate and a more comprehensive assessment metric is required. The CO2 equivalent emissions using the global temperature change potential (GTP) metric indicate that after 50 years the net global mean effect of current emissions is close to zero through cancellation of warming by CO2 and cooling by sulphate and nitrogen oxides.  相似文献   
26.
Jüssi M  Härkönen T  Helle E  Jüssi I 《Ambio》2008,37(2):80-85
Baltic grey seals (Halichoerus grypus) alternate between land and ice breeding, depending on ice conditions. We show that the fitness of grey seal females in terms of pup mortality and quality is reduced when breeding on land as compared with ice. The mean preweaning mortality rate on land was 21.1% (range 0% to 31.6%), and correlated with birth density (range 0.5-5.2 pups 100 m(-2)). The mean mortality rate on ice was 1.5%, where the highest density was 0.2 pups 100 m(-2) in particularly dense breeding groups. Mean weights of pups born on ice were significantly greater (48.3 +/- 8.1 kg) at the onset of moult as compared with pups born on land (37.4 +/- 7.8 kg). Because indices of life-time net reproductive rate (pup survival) and pup quality (weaning weight and health) were more auspicious on ice as compared with land, diminishing ice fields will lower the fitness of Baltic grey seal females and substantially increase the risk for quasi-extinction.  相似文献   
27.
A chemical absorption, post-combustion CO2 capture unit is simulated and an exergy analysis has been conducted, including irreversibility calculations for all process units. By pinpointing major irreversibilities, new proposals for efficient energy integrated chemical absorption process are suggested. Further, a natural-gas combined-cycle power plant with a CO2 capture unit has been analyzed on an exergetic basis. By defining exergy balances and black-box models for plant units, investigation has been made to determine effect of each unit on the overall exergy efficiency. Simulation of the chemical absorption plant was done using UniSim Design software with Amines Property Package. For natural-gas combined-cycle design, GT PRO software (Thermoflow, Inc.) has been used. For exergy calculations, spreadsheets are created with Microsoft Excel by importing data from UniSim and GT PRO. Results show the exergy efficiency of 21.2% for the chemical absorption CO2 capture unit and 67% for the CO2 compression unit. The total exergy efficiency of CO2 capture and compression unit is 31.6%.  相似文献   
28.
The evolution of alternative male mating phenotypes inevitably involves variation in risk or intensity of sperm competition. Males that typically mate in disfavoured roles (i.e. sneakers/parasitic males) are predicted to experience higher magnitudes of sperm competition than males mating in favoured roles (preferred by females/exhibiting mate monopolisation). Here, we investigated whether two distinct male phenotypes in corkwing wrasse (Symphodus melops) differ with respect to adaptations for sperm competition in terms of sperm quantity, sperm motility and fertilising capacity. We found that males exhibiting female mimicry (disfavoured role) had both absolutely and relatively larger gonads than males with typical secondary sexual characters (favoured role). Moreover, a higher proportion of sperm from female mimics was motile 5 min after activation compared to sperm of territorial males. There were, however, no differences in sperm concentration or in in vitro fertilisation ability between the two male morphs. We also examined whether the male phenotypes differed in some immune parameters and if any such variation is associated with sperm traits. Current theories predict that ejaculate quality should be negatively correlated with the level of immunocompetence. Territorial males had relatively heavier spleens than female mimics, but whether this reflects differing immunocompetence is uncertain, since the spleen is also an important organ for erythrocyte storage. Furthermore, there were no differences in the densities of circulating lymphocytes or granulocytes, and the immune parameters did not covary with the sperm traits. Differences in immunocompetence are therefore unlikely to provide a major proximate explanation for variations in sperm traits in corkwing wrasse.  相似文献   
29.
Knowledge of socio-demographic factors affecting attitudes to and perception of risk is an important instrument in enhancing efficiencies of interventions. The authors evaluated whether socio-demographic variables affected attitudes to an environmental issue (securing future drinking water). An important aspect was the delay between time of environmental pollution and time of human exposure and thereby potential health risk. Gender, education, place of residence and age all influenced the extent to which individuals were willing to allocate present resources to alleviate a future problem. Specifically, people above the age of 50 appeared more reluctant to pay for an intervention against a future potential health threat. The authors found a significant correlation between attitude and willingness to pay (WTP). In the authors' scenarios, the WTP variable worked more as a dichotomous variable than as a continuous variable, stressing the importance and relevance of the WTP=0 answers.  相似文献   
30.
Monitoring of the marine environment for radioactivity, for both radiological protection and oceanographic purposes, remains an expensive and labour intensive activity due to the large sample volumes needed and the complex and lengthy analytical procedures required to measure low levels of contamination. Because of this, some consideration must be given to the design of sampling plans to ensure effective and efficient sampling that can be defended on the basis of scientific rationale. This article tests the hypothesis that geostatistical techniques may prove of use in the optimisation and design of sampling regimes for the monitoring of temporal fluctuations in the levels of technetium at a location in the Norwegian Arctic marine environment. The level of temporal correlation exhibited by two relevant time series was investigated and the information used to observe the effect of sampling frequency on the production of monthly estimates of activity of technetium in both seawater and seaweed. The results indicate that reduced sampling frequency allows production of estimates that acceptably replicate the actual data and that use of geostatistical procedures may offer advantages in the planning of monitoring systems for marine radioactivity. The use of an oceanographic model was also investigated as a means of assessing the temporal correlation prior to actual sampling, an approach that may offer significant advantages by reducing the need to have lengthy time series prior to designing sampling regimes.  相似文献   
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