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The water lead concentrations measured in the homes of children who were part of the Edinburgh Lead study are related to the characteristics of the water supply and the household plumbing. At the time of the study one of the City of Edinburgh's two water supplies was lime treated to reduce plumbosolvency but in the second supply this treatment had not yet become effective. This allows us to estimate the extent to which this type of water treatment reduces water lead concentrations, in houses with lead plumbing, to comply with existing and proposed limits for lead in water. The kitchen cold water was supplied from a lead storage tank in 69 (15%) of the houses. These houses had the highest lead concentrations and water treTo whom correrspondence should be addressed.  相似文献   
2.
Methane oxidation capacity of soil from an experimentalsite in Northwest England was strongly dependent on temperatureand percentage water holding capacity. The soil had a distincttemperature optimum of 25 °C, with capacity for net methaneoxidation being completely lost below 5 and greater than37 °C. Optimum percentage water holding capacity for methaneoxidation was in the range 30–60%, with significant reductions inmethane oxidation rates in soils outside this range. Organic andmineral layers within the soil showed differences in potentialmethane oxidation rate, with methane oxidation being most rapid inthe buried organic layer and least rapid in the surface organiclayer. The importance of soil structure and gas diffusionlimitation is underlined, as is the strong temperature dependenceof methane oxidation when such diffusion limitation is removed.  相似文献   
3.

This paper describes a process to develop and establish an environmental policy and its associated environmental targets, objectives, and management programmes. The environmental policy is defined in a statement which addresses the company expectations for programmes that are important to assure adequate environmental protection and define its future commitment towards preventing pollution and continuously improving the effectiveness of its environmental protection programmes. A set of environmental objectives, derived from the policy, define the overall goals which will ensure that the company's environmental performance will remain consistent with the commitment identified in its policy when its environmental management system (EMS) is implemented, Environmental targets reflect the requirements and standards that the company must strive to achieve each objective and minimize any harmful environmental impacts from its production and manufacturing processes or other activities. In addition to defining specific targets, environmental management programmes are also used to guide EMS implementation. These programmes, however, must provide the company with the necessary flexibility to select the most appropriate technologies to enhance its own processes and prudently allocate its available financial resources in areas that return the greatest overall environmental benefit.Though they are expected to allow some discretion in the allocation of resources targeted towards environmental protection, EMS programmes must also provide assurance that the corporation environmental policy, objectives, targets, and management programmes do not result in a facility failure to adhere to all of its certification requirements. The principle and factors described in this article should be considered to the extent that they are necessary and practical.  相似文献   
4.
This paper presents results from research conducted to provide a high level techno-economic and performance assessments of various emerging technologies for capturing CO2 from the air, directly and indirectly, on a life-cycle basis. The technologies assessed include ‘artificial trees’, the soda lime process, augmented ocean disposal, biochar and bio-energy with carbon capture and storage.These technologies are subjected to quantitative and qualitative analyses, based on the most recent peer reviewed data in the literature, to identify their potential performance as well as the technical and non-technical barriers to their adoption and scale up. Key findings for each technology are presented which seek to highlight the state of technological development and research needs, the anticipated life cycle capture cost in $/tCO2 based on their potential to deliver a 0.1 ppm CO2 reduction per annum, policy requirements for scale up and, in light of these findings, the likely role that they will play in addressing climate change and broader environmental issues in the medium to long term.The key finding from the work is that the degree of scale-up required for negative emissions technologies to have a material impact on atmospheric emissions (i.e. at a ppm level) is probably unrealistic in less than 20 years. Therefore, emissions prevention efforts should remain the main focus in addressing climate change and the likely role for negative emissions technologies will be in augmenting a suite of mitigation measures targeting economically or practically difficult emissions.  相似文献   
5.
The impact of disturbance from construction work around Cardiff Bay, south Wales, on the densities and feeding behavior of seven waterbird species was studied over an 11-year period. Construction of a barrage across the mouth of the bay has subsequently resulted in its impoundment; other major works included the construction of a bridge carrying a divided highway. Construction work disturbance significantly reduced the densities of five species—green-winged teal (Anas crecca), Eurasian oystercatcher (Haematopus ostralegus), dunlin (Calidris alpina), Eurasian curlew (Numenius arquata), and common redshank (Tringa totanus)—on adjacent intertidal mudflats, and thus the overall carrying capacity of the bay. Construction work also reduced the feeding activity of Eurasian oystercatcher, dunlin, and common redshank on these mudflats. The possible impact of the loss of birds from these mudflats upon the populations that the bay supported is discussed. Evidence from other local studies suggests that the displacement of common redshank from these mudflats did not contribute to a decline in this species.  相似文献   
6.
A diverse range of microorganisms capable of growth on phenylacetic acid as the sole source of carbon and energy were isolated from soil. Sixty six different isolates were identified and grouped according to 16S rRNA gene RFLP analysis. Subsequent sequencing of 16S rDNA from selected strains allowed further characterization of the phenylacetic acid degrading population isolated from soil. Nearly half (30) of the isolates are Bacillus species while the rest of the isolates are strains from a variety of genera namely, Arthrobacter, Pseudomonas, Rhodococcus, Acinetobacter, Enterobacter, Flavobacterium, and Paenibacillus. Sixty-one of the sixty-six strains reproducibly grew in defined minimal liquid culture medium (E2). All strains isolated grew when at least one hydroxylated derivative of phenylacetic acid was supplied as the carbon source, while 59 out of the 61 strains tested, accumulated ortho-hydroxyphenylacetic acid in the assay buffer; when pulsed with phenylacetic acid. Oxygen consumption experiments failed to indicate a clear link between phenylacetic acid and hydroxy-substituted phenylacetic acid in isolates from a broad range of genera.  相似文献   
7.
In behavior-based individual-based models (IBMs), demographic functions are emergent properties of the model and are not built into the model structure itself, as is the case with the more widely used demography-based IBMs. Our behavior-based IBM represents the physiology and behavioral decision making of individual animals and, from that, predicts how many survive the winter nonbreeding season, an important component of fitness. This paper provides the first test of such a model by predicting the change in winter mortality of a charadriid shorebird following removal of intertidal feeding habitat, the main effect of which was to increase bird density. After adjusting one calibration parameter to the level required to replicate the observed mortality rate before habitat loss, the model predicted that mortality would increase by 3.65%, which compares well with the observed increase of 3.17%. The implication that mortality was density-dependent was confirmed by predicting mortality over a range of bird densities. Further simulations showed that the density dependence was due to an increase in both interference and depletion competition as bird density increased. Other simulations suggested that an additional area of mudflat, equivalent to only 10% of the area that had been lost, would be needed by way of mitigation to return mortality to its original level. Being situated at a high shore level with the flow of water in and out impeded by inlet pipes, the mitigating mudflat would be accessible to birds when all mudflats in the estuary were covered at high tide, thus providing the birds with extra feeding time and not just a small replacement mudflat. Apart from providing the first, and confidence-raising, test of a behavior-based IBM, the results suggest (1) that the chosen calibration procedure was effective; (2) that where no new fieldwork is required, and despite being parameter rich, a behavior-based IBM can be parameterized quickly (few weeks), and thus cheaply, because so many of the parameter values can be obtained from the literature and are embedded in the model; and (3) that behavior-based IBMs can be used to explore system behavior (e.g., the role of depletion competition and interference competition in density-dependent mortality).  相似文献   
8.
ABSTRACT

The transition to more sustainable energy systems has set about redefining the social roles and responsibilities of citizens. Implicit in this are expectations around participation, though the precise contours of what this might mean remain open. Debates around the energy transition have been skewed towards a normative construct of what it means to be a ‘good citizen’, the parameters for which are shaped by predetermined visions of statist and/or market-driven determinations of the energy systems of the future. This article argues that concepts such as ‘energy citizen’ are co-opted to reflect popular neoliberal discourses, and ignore crucial questions of unequal agency and access to resources. Paradoxically, official discourses that push responsibility for the energy transition onto the ‘citizen-as-consumer’ effectively remove agency from citizens, leaving them largely disconnected and disempowered. Consequently, energy citizenship needs to be reconceptualised to incorporate more collective and inclusive contexts for action. Considering how much energy consumption occurs in (traditionally female) domestic spheres, do conventional notions of citizenship (especially with regards to its associated rights and duties) need to be recalibrated in order for the concept to be usefully applied to the energy transition?  相似文献   
9.
Determining the magnitude of homing behaviour within migratory fish species is essential for their conservation and management. We tested for population genetic structuring in the anadromous alosines, Alosa alosa and A. fallax fallax, to establish fidelity of stocks to spawning grounds in the United Kingdom and Ireland. Considerable genetic differences were present among populations of both species, suggesting strong fidelity to breeding grounds and compatible with homing to natal origins. Moreover, the genetic structure of A. fallax fallax showed a clear pattern of isolation-by-distance, consistent with breeding populations exchanging migrants primarily with neighbouring populations. Spatial genetic differences were on average much greater than temporal differences, indicating relatively stable genetic structure. Comparing anadromous A. fallax fallax populations to the landlocked Killarney shad subspecies, A. fallax killarnensis (Ireland), demonstrated a long history of separation. These results demonstrating regional stock structure within the British Isles will inform practical management of stocks and their spawning habitats.  相似文献   
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