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51.
Grace Michell 《The Australian geographer》2013,44(4):435-459
Social issues are critical to the mining industry. This study investigates how social issues have been, and are being, assessed and managed within this industry through a case study of Northparkes Mines in central west New South Wales (NSW). The research involved 29 interviews with mining executives, environmental consultants and citizens of Parkes, plus a document analysis of four environmental impact statements prepared between 1990 and 2012. Where appropriate, findings were extrapolated to the wider mining industry. The standard for social impact assessment in NSW and emerging industry guidelines on social responsibility were analysed against internationally accepted good practice. Interviews indicated greater potential to recognise the social impacts of mining in NSW and identified good practice impact assessment as only one component of a successful community engagement strategy. Complementary strategies are essential to extend the benefits of development to local communities and for companies to establish a ‘social licence to operate’. The successful approach taken by Northparkes Mines combined good practice impact assessment with a localised workforce, an integrated management team and context-specific community engagement practices. This study highlights that local communities can be empowered through development, that benefits can extend to both the community and the business and that the ongoing management of social issues will increasingly be critical to the success of the mining industry. 相似文献
52.
Normalized gas chromatograms of the normal alkane fraction extracted from 22 surface sediment samples from a salt marsh near Georgetown, South Carolina were submitted to an unmixing algorithm. This algorithm identified four end-number contributors, three of which very closely resemble n-alkane patterns from dominant plant species. The fourth end-member is apparently a mixture. Proportioning of the n-alkane patterns of the sediments suggests that the patterns reflect contributions from living surface plant material and dead plant material brought in by tides. The successful unmixing of complex patterns of alkanes from marsh sediments suggests a valuable new technique for the interpretation of chromatographic data. 相似文献
53.
Watson Leighton M. Carpenter Brad Thompson Kevin Johnson Jeffrey B. 《Natural Hazards》2022,111(1):949-972
Natural Hazards - Snow avalanches pose a hazard in alpine environments. There is a need to improve monitoring capabilities in order to reliably detect and locate avalanche activity, which will help... 相似文献
54.
M. A. Carpenter 《Physics and Chemistry of Minerals》1992,19(1):1-24
Variations in the equilibrium degree of Al/Si order in anorthite have been investigated experimentally over the temperature range 800-1535° C. Spontaneous strain measurements give the temperature dependence of the macroscopic order parameter, Q, defined with respect to the \(C\bar 1 \rightleftharpoons I\bar 1\) phase transition, while high temperature solution calorimetric data allow the relationship between Q and excess enthalpy, H, to be determined. The thermodynamic behaviour can be described by a Landau expansion in one order parameter if the transition is first order in character, with an equilibrium transition temperature, T tr, of ~2595 K and a jump in Q from 0 to ~0.65 at Ttr. The coefficients in this Landau expansion have been allowed to vary with composition, using Q=1 at 0 K for pure anorthite as a reference point for the order parameter. Published data for H and Q at different compositions allow the calibration of the additional parameters such that the free energy due to the \(C\bar 1 \rightleftharpoons I\bar 1\) transition in anorthite-rich plagioclase feldspars may be expressed (in cal. mole-1) as: \(\begin{gathered}G = \tfrac{1}{2} \cdot 9(T - 2283 + 2525X_{Ab} )Q^2 \\ {\text{ + }}\tfrac{1}{4}( - 26642 + 121100X_{Ab} )Q^4 \\ {\text{ + }}\tfrac{1}{6}(47395 - 98663X_{Ab} )Q^6 \\ \end{gathered}\) where X Ab is the mole fraction of albite component. The nature of the transition changes from first order in pure anorthite through tricritical at ~An78 to second order, with increasing albite content. The magnitude of the free energy of \()\) ordering reduces markedly as X Ab increases. At ~700° C incommensurate ordering in crystals with compositions ~An50–An70 needs to have an associated free energy reduction of only a few hundred calories to provide a more stable structure. These results, together with a simple mixing model for the disordered ( \()\) ) solid solution, an assumed tricritical model for the incommensurate ordering and published data for ordering in albite have been used to calculate a set of possible free energy relations for the plagioclase system. The incommensurate structure should appear on the equilibrium phase diagram, but its apparent stability with respect to the assemblage albite plus anorthite at low temperatures depends on the values assigned to the mixing parameters of the $$$$ solid solution. 相似文献
55.
Benony K. Kortatsi Collins K. Tay Geophrey Anornu Ebenezer Hayford Grace A. Dartey 《Environmental Geology》2008,53(8):1651-1662
Alumino-silicate mineral dissolution, cation exchange, reductive dissolution of hematite and goethite, oxidation of pyrite
and arsenopyrite are processes that influence groundwater quality in the Offin Basin. The main aim of this study was to characterise
groundwater and delineate relevant water–rock interactions that control the evolution of water quality in Offin Basin, a major
gold mining area in Ghana. Boreholes, dug wells, springs and mine drainage samples were analysed for major ions, minor and
trace elements. Major ion study results show that the groundwater is, principally, Ca–Mg–HCO3 or Na–Mg–Ca–HCO3 in character, mildly acidic and low in conductivity. Groundwater acidification is principally due to natural biogeochemical
processes. Though acidic, the groundwater has positive acid neutralising potential provided by the dissolution of alumino-silicates
and mafic rocks. Trace elements’ loading (except arsenic and iron) of groundwater is generally low. Reductive dissolution
of iron minerals in the presence of organic matter is responsible for high-iron concentration in areas underlain by granitoids.
Elsewhere pyrite and arsenopyrite oxidation is the plausible process for iron and arsenic mobilisation. Approximately 19 and
46% of the boreholes have arsenic and iron concentrations exceeding the WHO’s (Guidelines for drinking water quality. Final
task group meeting. WHO Press, World Health Organization, Geneva, 2004) maximum acceptable limits of 10 μg l−1 and 0.3 mg l−1, for drinking water. 相似文献
56.
Jessica L. Nagel Hilary A. Neckles Glenn R. Guntenspergen Erika N. Rocks Donald R. SchoolmasterJr James B. Grace Dennis Skidds Sara Stevens 《Estuaries and Coasts》2018,41(2):334-348
Tools for assessing and communicating salt marsh condition are essential to guide decisions aimed at maintaining or restoring ecosystem integrity and services. Multimetric indices (MMIs) are increasingly used to provide integrated assessments of ecosystem condition. We employed a theory-based approach that considers the multivariate relationship of metrics with human disturbance to construct a salt marsh MMI for five National Parks in the northeastern USA. We quantified the degree of human disturbance for each marsh using the first principal component score from a principal components analysis of physical, chemical, and land use stressors. We then applied a metric selection algorithm to different combinations of about 45 vegetation and nekton metrics (e.g., species abundance, species richness, and ecological and functional classifications) derived from multi-year monitoring data. While MMIs derived from nekton or vegetation metrics alone were strongly correlated with human disturbance (r values from ?0.80 to ?0.93), an MMI derived from both vegetation and nekton metrics yielded an exceptionally strong correlation with disturbance (r = ?0.96). Individual MMIs included from one to five metrics. The metric-assembly algorithm yielded parsimonious MMIs that exhibit the greatest possible correlations with disturbance in a way that is objective, efficient, and reproducible. 相似文献
57.
58.
The formation factor relates bulk resistivity to pore fluid resistivity in porous materials. Understanding the formation factor is essential in using electrical and electromagnetic methods to monitor leachate accumulations and movements both within and around landfills. Specifically, the formation factor allows leachate resistivity, the degree of saturation, and, possibly, even the hydraulic conductivity of the waste to be estimated from non-invasive surface measurements. In this study, apparent formation factors are computed for three landfills with different types of waste as well as sediments contaminated by landfill leachate. Resistivity soundings at the closed Mallard North landfill in suburban Chicago (Illinois, USA) mapped leachate surfaces that were confirmed by monitoring wells. The resistivity of leachate-saturated waste from resistivity sounding inversions was then divided by the leachate resistivity values measured in-situ to compute apparent formation factors (Fa) ranging from 1.6 to 4.9. A global Fa of 3.0±1.9 was computed for the entire monitored portion of this landfill At a nearby mixed laboratory waste landfill, a 2D inverted resistivity section was used to compute an Fa of 2.9. Finally, a distinctly different Fa value of 10.6±2.8 was computed for leachate-saturated retorted oil and organic compounds. The Fa for aquifers containing contaminated groundwater fall in the same range as aquifers with normal groundwater, 1.7-3.9. However, models from inverted sounding curves over these contaminated areas exhibit unusually low resistivity layers, which may be diagnostic of contamination. 相似文献
59.
Grace Relf James M. Kendra Robert M. Schwartz Daniel J. Leathers Delphis F. Levia 《Natural Hazards》2015,78(1):333-354
Slushflows are natural hazards that pose considerable danger to communities across the globe. These events are characterized by the rapid mass movement of water-inundated snow downslope, and they cause economic damage as well as fatalities in many different climates and regions. As the global climate changes and human populations and industries potentially expand to higher latitudes, it will be important to fully understand the slushflow hazard since an anticipated increase in the frequency of rain-on-snow events and an earlier spring thaw would likely increase the probability of slushflows. This article: (1) summarizes the factors that favor the development of slushflows; (2) discusses the hazard management implications of slushflows; (3) examines the policies employed to prevent and mitigate slushflow damage; and (4) sets out the need for modifications in hazard management systems. Conclusions drawn hope to address future research needs in an effort to create policies that better suit the needs of at-risk communities. 相似文献
60.
S. A. Penkett K. C. Clemitshaw N. H. Savage R. A. Burgess L. M. Cardenas L. J. Carpenter G. G. McFadyen J. N. Cape 《Journal of Atmospheric Chemistry》1999,33(2):111-128
Detailed studies have been made of the behaviour of gases and radicals involved in the production of oxidants at the Weybourne Atmospheric Observatory in both summertime and wintertime conditions. In June 1995 the range of meteorological conditions experienced varied such that ozone destruction was observed in clean northerly air flows reaching Weybourne down the North Sea from the Arctic, and ozone production was observed in varying degrees in air with different loadings of nitrogen oxides and other precursors. The transition point for ozone destruction to ozone production occurred at a nitric oxide concentration of the order of 50 pptv. Plumes of polluted air from various urban areas in the U.K. were experienced in the June campaign at Weybourne. Quantitative studies of ozone production in a plume from the Birmingham conurbation on 18 June 1995 showed that the measurement of ozone production agreed well with calculated production rates from the product of the nitric oxide and peroxy radical concentrations (r2=0.9). In wintertime conditions (October–November 1994) evidence was also found for oxidant production, defined as the sum of O3+NO2. At this time of year the peroxy radical concentrations (RO2) were much lower than observed in the summertime and the nitric oxide (NO) was much higher. There was still sufficient RO2 during the day, however, for a slow accumulation of oxidant. Confirmatory evidence for this comes from the diurnal co-variance of (O3+NO2) with PAN, an excellent tracer of tropospheric photochemistry. The same type of covariance occurs in summer between PAN and ozone. The results obtained in these series of measurements are pertinent to understanding the measures necessary to control production of regional photochemical air pollution, and to the production of ozone throughout the northern hemisphere in winter. 相似文献