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71.
ABSTRACT

This paper presents a qualitative case study of community participation in local air quality management in Nottingham (UK). We analyse Nottingham’s response to a “clean air zone” mandate: despite national government and local community support of this congestion charging policy, the City Council rejected the measure. We focus on the policy framing, with data from policy documents, interviews with government and non-government actors, and observation in local activities. We found that community groups build links with local government in two ways: (1) as a coalition against the national government and austerity measures, and (2) as “neutral”, non-expert communicators of air pollution as an “invisible” policy problem. We show how this invisibility plays a significant role in factors such as trust, risk, responsibility, and policy communication. This research has theoretical implications for the communication of air pollution and practical implications for cities looking to implement similar transport-oriented strategies.  相似文献   
72.
This paper examines some of the theoretical and methodological issues arising from the process of conceptualising and eliciting values for environmental risk in the context of heterogeneous expert knowledge. Drawing on the experience of a recent research project examining the relationship between livestock farming systems and microbial watercourse pollution the paper reflects critically upon efforts to develop an interdisciplinary assessment of the factors that may affect the loss of potential pathogens from agricultural land to water courses as the basis for targeting high risk fields and farms. The paper describes the procedures for designing the natural and cultural parameters that surround microbial risks and the issues that are raised for making whole system assessments workable based on contrasting and unstable systems of disciplinary insight. Situated within claims about the need for generating reliable and widely applicable assessments of environmental risk the paper suggests that interdisciplinary working raises important issues about the role of ‘uncertain’ knowledge in the management of ‘known’ risks.  相似文献   
73.
This research advances the understanding of the location of perceived landscape values through a statistically based approach to spatial analysis of value densities. Survey data were obtained from a sample of people living in and using the Murray River region, Australia, where declining environmental quality prompted a reevaluation of its conservation status. When densities of 12 perceived landscape values were mapped using geographic information systems (GIS), valued places clustered along the entire river bank and in associated National/State Parks and reserves. While simple density mapping revealed high value densities in various locations, it did not indicate what density of a landscape value could be regarded as a statistically significant hotspot or distinguish whether overlapping areas of high density for different values indicate identical or adjacent locations. A spatial statistic Getis–Ord Gi* was used to indicate statistically significant spatial clusters of high value densities or “hotspots”. Of 251 hotspots, 40% were for single non-use values, primarily spiritual, therapeutic or intrinsic. Four hotspots had 11 landscape values. Two, lacking economic value, were located in ecologically important river red gum forests and two, lacking wilderness value, were near the major towns of Echuca-Moama and Albury-Wodonga. Hotspots for eight values showed statistically significant associations with another value. There were high associations between learning and heritage values while economic and biological diversity values showed moderate associations with several other direct and indirect use values. This approach may improve confidence in the interpretation of spatial analysis of landscape values by enhancing understanding of value relationships.  相似文献   
74.
Abstract

The elemental compositions of the water-soluble and acid-digestible fractions of 24-hr integrated fine particulate matter (PM2.5) samples collected in Steubenville, OH, from 2000 to 2002 were determined using dynamic reaction cell inductively coupled plasma-mass spectrometry. The water-soluble elemental compositions of PM2.5 samples collected at four satellite monitoring sites in the surrounding region were also determined. Fe was the most abundant but least water soluble of the elements determined at the Steubenville site, having a mean ambient concentration of 272 µg/m3 and a median fractional solubility of 6%. Fe solubility and its correlations with SO4 2? and temperature varied significantly by season, consistent with the hypothesis that secondary sulfates may help to mobilize soluble Fe under suitable summertime photochemical conditions. Significantly higher ambient concentrations were observed at Steubenville than at each of the four satellite sites for 10 of the 18 elements (Al, As, Ca, Cd, Fe, Mg, Mn, Na, Pb, and Zn) determined in the water-soluble PM2.5 fraction. Concentrations of Fe, Mn, and Zn at Steubenville were substantially higher than concentrations reported recently for larger U.S. cities. Receptor modeling identified seven sources affecting the Steubenville site. An (NH4)2SO4-dominated source, likely representing secondary PM2.5 from coal-fired plants to the west and southwest of Steubenville, accounted for 42% of the PM2.5 mass, and two sources likely dominated by emissions from motor vehicles and from iron and steel facilities in the immediate Steubenville vicinity accounted for 20% and 10%, respectively. Other sources included an NH4NO3 source (15%), a crustal source (6%), a mixed nonferrous metals and industrial source (3%), and a primary coal combustion source (3%). Results suggest the importance of very different regional and local source mechanisms in contributing to PM2.5 mass at Steubenville and reinforce the need for further research to elucidate whether metals such as Fe, Mn, and Zn play a role in the PM2.5 health effects observed previously there.  相似文献   
75.

Introduction

Through a meta-analysis, this study investigated the relation of errors and violations from the Driver Behaviour Questionnaire (DBQ) to accident involvement.

Method

We identified 174 studies using the DBQ, and a correlation of self-reported accidents with errors could be established in 32 samples and with violations in 42 samples.

Results

The results showed that violations predicted accidents with an overall correlation of .13 when based on zero-order effects reported in tabular form, and with an overall correlation of .07 for effects reported in multivariate analysis, in tables reporting only significant effects, or in the text of a study. Errors predicted accidents with overall correlations of .10 and .06, respectively. The meta-analysis also showed that errors and violations correlated negatively with age and positively with exposure, and that males reported fewer errors and more violations than females. Supplementary analyses were conducted focusing on the moderating role of age, and on predicting accidents prospectively and retrospectively. Potential sources of bias are discussed, such as publication bias, measurement error, and consistency motif.

Impact on Industry

The DBQ is a prominent measurement scale to examine drivers’ self-reported aberrant behaviors. The present study provides information about the validity of the DBQ and therefore has strong relevance for researchers and road safety practitioners who seek to obtain insight into driving behaviors of a population of interest.  相似文献   
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78.
ABSTRACT: Measured stream discharge plus calculated ground water discharge (total measured runoff) were compared with runoff calculated by the unit-runoff method for the two largest watersheds of Mirror Lake for 1981–1983. Runoff calculated by the unit-runoff method, using Hubbard Brook watershed 3 as the index watershed, was greater than the total measured runoff into Mirror Lake during periods of high flow and slightly less than the total measured runoff into Mirror Lake during periods of low flow. Annual calculated unit runoff was 17 to 37 percent greater than total measured runoff. Differences in monthly runoff are far greater, ranging from 0 to greater than 100 percent. For high flows the calculated unit runoff is about 2 times greater than total measured runoff. For low flows the northwest basin of Mirror Lake has the greatest ground water contribution compared to the other two basins. In contrast, Hubbard Brook watershed 3 has the least ground water contribution.  相似文献   
79.
This paper describes a quantitative investigation of relationships between the growth of phytoplankton, and climatic and hydrodynamci conditions in temperate fjords with marked tides, as exemplified by Puget Sound, Washington (USA). Algal growth in the open waters of the central basin of the Sound is dominated by a number of intense blooms beginning in late April or May and recurring throughout the summer. Rarely, and only briefly, does nitrate become exhausted. The phytoplankton production rate in the central basin of Puget Sound is about 465 g C m-2 year-1. During the springs of 1966 and 1967, oceanographic measurements were carried out at a mid-channel station with sufficient frequency to allow investigation of physical and biological processes with time scales of the order of a day. The principal investigative tool is a numerical model in which the hydrodynamical conditions are represented by an approximate analysis of the gravitational convection mode of circulation. Algal concentration is represented as a continous function of space and time in the model which ascribes changes in phytoplankton density to variations in photosynthetic and respiratory activity, algal sinking, grazing by herbivores, and to mixing and advection. Computations adequately reproduce the principal features of phytoplankton concentrations observed during 75 days and 35 days in the springs of 1966 and 1967, respectively. Numerical experiments assess the relative importance of various processes which govern the level of primary production in Puget Sound. It is concluded that phytoplankton growth is limited by a combination of factors, including vertical advection and turbulence, modulation of underwater light intensity by self-shading and inorganic particulates, sinking of algal cells, and occasional rapid horizontal advection of the population from the area by sustained winds. The high primary productivity of the Sound is due to intensive upward transport of nitrate by the estuarine mechanism. These results should be generally applicable to other temperate fjords because of the largely conventional choice of the biological functions.  相似文献   
80.
Determination of the nature and extent of the connection between groundwater and surface water is of paramount importance to managing water supplies. The development of analyses that detail the surface water‐groundwater system may lead to more effective utilization of available water. A tool was developed to help determine the effects of groundwater and surface water interactions. The software tool includes two graphic user interfaces to allow full compatibility with numerical MODFLOW groundwater models. This case study shows the tool, in conjunction with MODFLOW groundwater models and carefully designed scenarios, can successfully calculate the rates of stream‐groundwater interactions, thereby providing the basis for designating management areas with the most significant hydrologic impact. This tool can be applied in other regions with similar settings and needs for integrated water management.  相似文献   
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