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11.
The assessment of sustainable development is a relatively recent advent in policy and the evaluation of industry structural adjustments. Although the elements of economic and environmental assessment have been relatively well developed and accepted, the effective inclusion of ‘social’ aspects in assessments of sustainable development are still being grappled with. 相似文献
12.
The energetics and structure of the hydrogarnet defect in grossular: A computer simulation study 总被引:1,自引:0,他引:1
We have used computer simulation methods to model the structure and energetics of the hydrogarnet defect in grossular. The predicted structure is in good agreement with experimental data. The calculated energy for the reaction of water with grossular to form the hydrogarnet defect is 1.02 Ev (98 kJ mol-1). This low energy of reaction suggests that such defects will be common in garnets where they could play an important role in effecting processes such as atomic transport. 相似文献
13.
14.
This paper describes an assessment of the ways in which water supply companies in England and Wales are adapting to climate change, evaluated in the context of a model of the adaptation process. The four components of the model are (i) awareness of and concern about the potential impacts of climate change, (ii) adaptation strategy, (iii) the concept of an adaptation space from which options are selected, and (iv) the notion that three groups of factors influence awareness, strategy and option selection: susceptibility to change, internal characteristics of the organisation, and regulatory and market context.Public water supply in England and Wales is provided by private sector companies, subject to environmental and economic regulation. Hydrological simulations suggest that climate change has the potential to reduce the reliability of supply sources over the next few decades. The industry in December 2004 completed a review of investment requirements over the next five years.Awareness of climate change is high in the water industry, but by developing assessment procedures and incorporating them into the investment review the regulators forced companies to consider explicitly the potential impacts of climate change in a consistent and rigorous manner. These analyses combined climate change with other pressures on water resources, and in practice companies did not attribute specific investment decisions or proposals to climate change or indeed any other individual drivers. The broad strategy adopted by all water supply companies – to maintain standards of service – is determined by regulatory controls and market considerations, but the degree of concern about the impacts of climate change and precise adaptation options necessary to address supply-demand imbalances varied between water supply companies, reflecting local geographic conditions. The water supply companies and regulators have different perspectives on the relative merits of supply-side and demand-side measures, reflecting different organisational priorities.The 2004 investment review determined that no specific actions were necessary to deal with future climate change, but that measures set in place – in terms of methodologies and investment in investigations into specific resource developments – provided a sound foundation for more specific actions in the next investment review in five years time. The paper concludes by summarising the factors assisting and constraining adaptation over the next few decades. 相似文献
15.
Analysis of three first-order leveling lines that traverse the White Wolf fault (site of the 1952 M = 7.7 earthquake), each resurveyed nine times between 1926 and 1974, reveals probable preseismic tilting, major coseismic movements, and a spatial association between these movements and the subsequently recognized southern California uplift. In examining the vertical control record, we have both searched for evidence of systematic errors and excluded from consideration portions of the lines contaminated by subsurface fluid and gas extraction. Movements have been referred to an invariant datum based on the 1926 position of tidal BM 8 in San Pedro, corrected for subsequent eustatic sea-level change.An 8 μrad up-to-the-north preseismic tilt (6 cm/7.5 km) was apparently recorded on two adjacent line segments within 10 km of the 1952 epicenter between 1942 and 1947. It is possible, however, that this tilt was in part caused by extraction-induced subsidence at one of the six releveled benchmarks. Data also show evidence of episodic tilts that are not earthquake related. At the junction of the Garlock and San Andreas faults, for example, an ≥5 μrad up-to-the-north tilt (7.2 cm/≤16 km) took place between Lebec and Grapevine within three months during 1964.Comparison of the 1947 and 1953 surveys, which includes the coseismic interval, shows that the SW-fault end (nearest the epicenter) and the central fault reach sustained four times the uplift recorded at the NE end of the fault (+72 cm SW, +53 cm Central, +16 cm NE). A regional postseismic uplift of 4 cm extended ≥25 km to either side of the fault after the main event, from 1953 to 1956. An interval of relative quiescence followed at least through 1959, in which the elevation change did not exceed ±3 cm.The detailed pattern of aseismic uplift demonstrates that movement proceeded in space—time pulses: one half of the uplift at the SW-fault end and extending southward occurred between 1959 and 1961, one half of the uplift at the NE-fault end and extending eastward occurred between 1961 and 1965, while the central fault reach sustained successive pulses of subsidence, uplift, and collapse (−4 cm, 1953–1960; +7 cm, 1960–1965; −2 cm, 1965–1970). In addition, the number of aftershocks concentrated near the fault ends increased in the NE relative to the SW from 1952 to 1974. These observations suggest that the aseismic uplift may have migrated northeastward from 1959 to 1965 at an approximate rate of 7–16 km/yr.Evidence for a mechanical coupling between the earthquake and the subsequent aseismic uplift is equivocal. At both fault ends, the major NWbounding flexure or tilted front of the southern California uplift is spatially coincident with the coseismic flexure that preceded it. In addition, the postulated migration of vertical deformation is similar to the 1952 seismic event in which the rupture initiated at the SW end of the fault and then propagated to the NE-fault end. However, the spatial distribution of aseismic uplift, nearly identical at both fault ends and to the south and east, and near zero in the central fault reach, is distinctly different from the nonuniform and localized coseismic deformation. 相似文献
16.
Market studies by Hydro Products identified industry interest in a guide wire deployed package consisting of an RCV-225 remotely controlled vehicle with launcher and a strong dexterous manipulator for drill ship support in water depths to approximately 2000 ft (sim 600 m). This paper discusses the design, production, and initial testing of a prototype unit. Anticipated capabilities provided for in the initial design include the ability to perform pre- and post-drilling site surveys, wellhead and riser television inspection, stabbing assist, AX/VX ring replacement, guide wire replacement assist, and debris removal. Provision for incorporation of further sensors and capabilities was given high priority. Future developments and plans for further testing are also enumerated. 相似文献
17.
Clumped isotope thermometry of carbonatites as an indicator of diagenetic alteration 总被引:2,自引:0,他引:2
We measure the clumped isotopic signature of carbonatites to assess the integrity of the clumped isotope paleothermometer over long timescales (107-109 years) and the susceptibility of the proxy to closed system re-equilibration of isotopes during burial diagenesis. We find pristine carbonatites that have primary oxygen isotope signatures, along with a Carrara marble standard, do not record clumped isotope signatures lighter than 0.31‰ suggesting atoms of carbon and oxygen freely exchange within the carbonate lattice at temperatures above 250-300 °C. There is no systematic trend in the clumped isotope signature of pristine carbonatites with age, although partial re-equilibration to lower temperatures can occur if a carbonatite has been exposed to burial temperatures for long periods of time. We conclude that the solid-state re-ordering of carbon and oxygen atoms is sufficiently slow to enable the use of clumped isotope paleothermometry on timescales of 108 years, but that diagenetic resetting can still occur, even without bulk recrystallization. In addition to the carbonatite data, an inorganic calibration of the clumped isotope paleothermometer for low temperature carbonates (7.5-77 °C) is presented and highlights the need for further inter-lab standardization. 相似文献
18.
European floods during the winter 1783/1784: scenarios of an extreme event during the ‘Little Ice Age’ 总被引:1,自引:0,他引:1
Rudolf Brázdil Gaston R. Demarée Mathias Deutsch Emmanuel Garnier Andrea Kiss Jürg Luterbacher Neil Macdonald Christian Rohr Petr Dobrovolný Petr Kolář Kateřina Chromá 《Theoretical and Applied Climatology》2010,100(1-2):163-189
The Lakagígar eruption in Iceland during 1783 was followed by the severe winter of 1783/1784, which was characterised by low temperatures, frozen soils, ice-bound watercourses and high rates of snow accumulation across much of Europe. Sudden warming coupled with rainfall led to rapid snowmelt, resulting in a series of flooding phases across much of Europe. The first phase of flooding occurred in late December 1783–early January 1784 in England, France, the Low Countries and historical Hungary. The second phase at the turn of February–March 1784 was of greater extent, generated by the melting of an unusually large accumulation of snow and river ice, affecting catchments across France and Central Europe (where it is still considered as one of the most disastrous known floods), throughout the Danube catchment and in southeast Central Europe. The third and final phase of flooding occurred mainly in historical Hungary during late March and early April 1784. The different impacts and consequences of the above floods on both local and regional scales were reflected in the economic and societal responses, material damage and human losses. The winter of 1783/1784 can be considered as typical, if severe, for the Little Ice Age period across much of Europe. 相似文献
19.
“I’m an imaginary figure”: Unravelling the mobility and marginalisation of Scottish Gypsy Travellers
Gypsy Travellers have a long history of marginalisation in Scotland, but their mobility remains an issue of particular contention. Drawing upon a series of interviews with Gypsy Travellers in the North-East of Scotland, this paper uncovers how power and politics permeate discourses on movement to legitimise the spatial ordering of this traditionally nomadic group. The paper begins by exploring the more hidden and subtle aspects of mobility, such as the emotional and imaginative ties to travel. It then shifts to document how Gypsy Travellers’ geographies have been compromised by discriminatory policies and practices, which demonstrate a misunderstanding of the heterogeneity of their mobility. Consequently, increasingly punitive policies have pushed many Gypsy Travellers to abandon their travelling ways to move into “fixed” housing, while others have been forced into states of perpetual motion. The overall goal of the paper is to unravel the discursive constructions of movement in the context of institutionalised power and to document the spatial ordering of Gypsy Travellers’ lives, whose marginality has been legitimised by laws, ideologically sustained and reproduced in policy documents. 相似文献
20.
Paul Augustinus Charles E. Barton Atun Zawadzki Kate Harle 《Environmental Earth Sciences》2010,61(3):625-639
Macquarie Harbour in southwest Tasmania, Australia, has been affected severely by the establishment of mines in nearby Queenstown
in the 1890s. As well as heavy metal-laden acid rock drainage from the Mount Lyell mine area, over 100 Mt of mine tailings
and slag were discharged into the Queen and Ring Rivers, with an estimated 10 Mt of mine tailings building a delta of ca.
2.5 km2 and ca. 10 Mt of fine tailings in the harbour beyond the delta. Coring of sediments throughout Macquarie Harbour indicated
that mine tailings accreted most rapidly close to the King River delta source with a significant reduction in thickness of
tailings and heavy metal contamination with increasing distance from the King River source. Close to the King River delta
the mine tailings are readily discriminated from the background estuarine sediments on the basis of visual logging of the
core (laminations, colour), sediment grain size, sediment magnetic susceptibility and elemental geochemistry, especially concentrations
of the heavy metals Cu, Zn and Pb. The high heavy metal concentrations are demonstrated by the very high contamination factors
(CF > 6) for Cu and Zn, with CF values mostly >50 for Cu for the mine-impacted sediments. Although the addition of mine waste
into the King River catchment has ceased, the catchment continues to be a source of these heavy metals due to acid rock drainage
and remobilisation of mine waste in storage in the river banks, river bed and delta. The addition of heavy metals to the harbour
sourced from the Mount Lyell mines preceded the advent of direct tailings disposal into the Queen River in 1915 with the metals
probably provided by acid rock drainage from the Mount Lyell mining area. 相似文献