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31.
T.H. Morrison C. McAlpine J.R. Rhodes A. Peterson P. Schmidt 《The Australian geographer》2010,41(4):521-538
The Australian government Caring for our Country (CfoC) program, first announced in 2008, has sought to build on and enhance previous experience with Australian natural resource management policy. This paper critically examines the initial design, planned delivery, and first round of competitive funding outcomes of the new program. This analysis shows that the initial design and delivery of the CfoC model was ad hoc, politicised, and lacking in transparency. The paper concludes that a more systematic and transparent approach for achieving sustainable environmental outcomes is required in order for this new program to achieve its intended objectives. These implications are of interest to Australian and international geographers, natural resource planners, scientists and policy makers concerned with the design, delivery and outcomes of large natural resource and environmental management programs. 相似文献
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Summary. A simple normal approximation is given for the joint probability density function of the polar coordinates (θ, φ) of a random vector following the Fisher distribution with arbitrary mean direction (θ0 , φ0 ). Two important applications of this approximation are discussed, and conditions for the validity of the approximation are investigated and summarized. 相似文献
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We use unit records of the 2006 census to show that access to the Internet in the home varies geographically in New Zealand primarily as a result of demographic and socio‐economic differences among individuals. Of particular significance is the much lower rates of domestic access experienced by Māori and Pacific Island individuals even after controlling for differences in their age, gender, education, income, occupation and settlement type. While differences in Internet access by ethnicity has been noted before, it is the magnitude and persistence of this difference in New Zealand after controlling for correlated factors that renders this study unique. Our results have important implications in an education environment increasingly reliant on Web access, but they also raise questions about the extent of access to the Internet outside the home. 相似文献
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A method is presented to evaluate ground water residence time in a zero‐valent iron (ZVI) permeable reactive barrier (PRB) using radon‐222 (222Rn) as a radioactive tracer. Residence time is a useful indicator of PRB hydraulic performance, with application to estimating the volumetric rate of ground water flow through a PRB, identifying flow heterogeneity, and characterizing flow conditions over time as a PRB matures. The tracer method relies on monitoring the decay of naturally occurring aqueous 222Rn as ground water flows through a PRB. Application of the method at a PRB site near Monticello, Utah, shows that after 8 years of operation, residence times in the ZVI range from 80 to 486 h and correlate well with chemical parameters (pH, Ca, SO4, and Fe) that indicate the relative residence time. Residence times in this case study are determined directly from the first‐order decay equation because we show no significant emanation of 222Rn within the PRB and no measurable loss of 222Rn other than by radioactive decay. 相似文献
39.
Detailed hydrogeochemical analysis of several samples of groundwater collected from parts of the Niger Delta, Nigeria has been carried out in an effort to assess the quality of groundwater in the area. Results obtained showed the groundwater in the area to be enriched in Na+, Ca++, Mg++, Cl–, HCO
3
-
, and SO
4
--
. The concentration of these ions as well as such parameters as salinity, total hardness, and TDS are below the World Health Organization (WHO) standards for drinking water. The concentration of Ca++ was found to be higher than Mg++ except in some areas very close to the coast suggesting the encroachment of saltwater. This encroachment of saltwater is further indicated by the general increase in Cl– and a decreased in HCO
3
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content towards the coast and Na/Cl ratios. On the basis of the present hydrogeochemical studies, five groundwater types have been recognized to occur in the area of study. These are (1) Sodium-Calcium-Magnesium-Bicarbonate type (Na-Ca-Mg-5HCO3), (2) Iron-Calcium-Bicarbonate type (Fe-Ca-4HCO3), (3) Sodium-Calcium-Magnesium-Sulfate type (
), (4) Iron-Chloride-Bicarbonate (Fe-Cl-HCO3), and (5) Magnesium-Chloride type (Mg-2Cl). The assemblage of groundwater types in the area shows that both compound and single groundwater types occur. The geochemical characteristics of the groundwaters are thought to be closely related to the peculiar geologic and hydrologic conditions that prevail in the Niger Delta area of Nigeria. 相似文献
40.
Nicola Morrison 《GeoJournal》2000,51(4):339-349
This paper provides an overview of the current literature on why difficulties are being experienced in letting social housing within England. The first part of the paper focuses on whether the management of the social housing stock, and in particular the current allocation system, has contributed to the growing number of difficult to let (DTL) properties in the social sector. Drawing on findings from in-depth interviews with twenty local authorities, the paper provides evidence to support this argument and also highlights a number of initiatives which authorities have adopted to fill DTL properties. However, the paper argues that these initiatives are likely to have limited value in the long run in stemming the fall in demand for social housing, particularly in the North of England. The second part of the paper focuses on the changing aspirations of tenants and the way that social housing is in competition with alternative forms to housing provision, such as private rented housing. It concludes by advocating that an appropriate response to difficulties in letting social housing has to go beyond internal housing management initiatives. Instead a more strategic approach needs to be adopted which builds up an understanding of the operation of the local housing market and the complex interaction of neighbourhoods. 相似文献