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41.
The XXIst International Congress of Photogrammetry and Remote Sensing was held at the Beijing International Convention Centre, China, from 3rd to 11th July 2008. Reports are given on the Congress as a whole, including the General Assembly, some Technical Commission activities and the Congress Exhibition. Papers from the Congress are published in Volume XXXVII of the International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences.  相似文献   
42.
High fluoride content in the groundwater is reported from parts of the Gad River Basin, Sindhudurg district, coastal Maharashtra, India. The fluoride content of up to 5 mg/l has been found in the groundwater in laterite, basalt and the Precambrian basement (gneiss) aquifers in the region. The presence of high fluoride in groundwater well above the permissible levels for consumption poses a serious health threat to the rural populace in the region. The presence of tourmaline bearing pegmatites in the Precambrian basement is considered as a potential fluorine source. Deep circulation of fluoride rich groundwater between the latetritised basalts and the underlying crystalline basement could be responsible for the occurrence of fluoride in both the shallow and deeper aquifers of the region.  相似文献   
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This study constrains the sediment provenance for the Late Cretaceous–Eocene strata of the Ager Basin, Spain, and reconstructs the interplay between foreland basin subsidence and sediment routing within the south-central Pyrenean foreland basin during the early phases of crustal shortening using detrital zircon (DZ) U-Pb-He double dating. Here we present and interpret 837 new DZ U-Pb ages, 113 of which are new DZ (U-Th)/He double-dated zircons. U-Pb-He double dating results allow for a clear differentiation between different foreland and hinterland sources of Variscan zircons (280–350 Ma) by leveraging the contrasting thermal histories of the Ebro Massif and Pyrenean orogen, recorded by the zircon (U-Th)/He (ZHe) ages, despite their indistinguishable U-Pb age signatures. Cretaceous–Paleocene sedimentary rocks, dominated by Variscan DZ U-Pb age components with Permian–Triassic (200–300 Ma) ZHe cooling ages, were sourced from the Ebro Massif south of the Ager Basin. A provenance shift occurred at the base of the Early Eocene Baronia Formation (ca. 53 Ma) to an eastern Pyrenean source (north-east of the Ager Basin) as evidenced by an abrupt change in paleocurrents, a change in DZ U-Pb signatures to age distributions dominated by Cambro-Silurian (420–520 Ma), Cadomian (520–700 Ma), and Proterozoic–Archean (>700 Ma) age components, and the prominent emergence of Cretaceous–Paleogene (<90 Ma) ZHe cooling ages. The Eocene Corçà Formation (ca. 50 Ma), characterized by the arrival of fully reset ZHe ages with very short lag times, signals the accumulation of sediment derived from the rapidly exhuming Pyrenean thrust sheets. While ZHe ages from the Corçà Formation are fully reset, zircon fission track (ZFT) ages preserve older inherited cooling ages, bracketing the exhumation level within the thrust sheets to ca. 6–8 km in the Early Eocene. These DZ ZHe ages yield exhumation rate estimates of ca. 0.03 km/Myr during the Late Cretaceous–Paleocene for the Ebro Massif and ca. 0.2–0.4 km/Myr during the Eocene for the eastern Pyrenees.  相似文献   
44.
The triggering factors of rock falls remain unknown due to a lack of exhaustive, regular and accurate surveys. Based on an inventory of 331 rock falls collected weekly between 2002 and 2009 from Veules‐les‐Roses to Le Treport (Upper Normandy), the relationships between coastal chalk cliff rock falls (dates and geomorphological features) and external factors commonly agreed as triggering (rainfall, temperature variations, tide and wind) are studied. The combination of multivariate statistical and empirical analyses indicates that (1) ‘cold and dry weather’ and ‘high rainfall and high wind’ are the conditions most likely to trigger rock falls, (2) the main triggering factors of rock falls are effective rainfall (for rock falls mostly between 200 and 1400 m3 or larger than 10 000 m3 and coming from the whole cliff face), freeze/thaw cycles (especially for rock falls smaller than 200 m3 and coming from the foot and top of the cliff face) and marine roughness (rock falls mainly smaller than 200 m3 and coming from the cliff foot). However, the contribution of each factor to triggering is difficult to determine because of combinations of factors (85% of 331 cases), relays of processes and hysteresis phenomena. In view of these first results, it is still presumptuous to predict the location and time of triggering of rock falls. However, the statistical and naturalistic approaches adopted and the observations made in this study are from an original database, and constitute a real starting point for the prediction and prevention of the hazard of coastal chalk cliff rock falls in Upper Normandy. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
45.
In 1991 the New Zealand health system began to experience what has been termed the `turbulent decade'. Without health sector consultation or public mandate, an era of imposed market oriented reforms began. These changed the overall culture of health care delivery and the expectations of New Zealanders regarding the role of the state in the provision of welfare. In retrospect the ideologically driven imposition of the market-oriented reforms was not an exercise of bold leadership but one of political arrogance and rejection of established community values. Within the community, the neoliberal experiment heightened income and health inequalities, created a loss of social cohesion and generally provoked feelings of powerlessness. In the health sector, the reforms polarised clinical and commercial cultures and changed the geography of health care delivery. This occurred not only because place was de-emphasised, but also because decentralisation of purchasing created four health systems with widely divergent contracting arrangements and standards of care. The lessons of the health reforms have been painful, and must not be lost. A fundamental lesson is that market approaches to the delivery of health care have major limitations and that the ultimate goal of a health system should be the equitable, effective and efficient provision of care, not the profitable sale of commodities. Since 1997 there has been a retreat from the market, although it is not clear whether recent policy developments represent a new or distinctive `third way' or a pragmatic `pick and mix', combining the best from the market and the managerialism first introduced by Labour in the 1980s. Quite clearly, the experiment with the market was not sustainable. Whether this will also be true of the more recent and pragmatic `pick and mix' approach of the `third way' to health care reform is uncertain. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
46.
The flooding of the abandoned iron mines of Lorraine leads to a degradation of the groundwater quality. Laboratory experiments allowed us to build a kinetic chemical model based on simple chemical mechanisms. During mining operations, pyrite oxidation and carbonate dissolution lead to the precipitation of gypsum. The local decrease of pH favours local dissolutions of minerals and releases ions that are fixed on cationic exchange sites. During the flooding of the mine workings, the dissolution of the newly precipitated gypsum, the precipitation of carbonates and cationic exchange reactions are responsible for the increase of the concentrations of sulphate, magnesium, sodium, potassium and strontium in water. Thereafter, these concentrations would decrease with the natural leaching of the mining reservoir. To cite this article: P. Collon et al., C. R. Geoscience 336 (2004).  相似文献   
47.
Despite the widespread incorporation of sustainable development into policy discourses, actually achieving the ‘win-win-win’ scenario of economic, environmental and social development continues to be problematic. Advocates of industrial ecology suggest that by shifting the basis of industrial production from a linear to a closed loop system, these gains can be achieved. In recent years, concepts drawn from industrial ecology have been used to plan and develop eco-industrial parks (EIPs) that seek to increase business competitiveness, reduce waste and pollution, create jobs and improve working conditions. Despite a growing interest in EIPs, there have been few empirically informed studies that seek to explore the potential contribution such EIPs may make to sustainable development. This paper contributes to a developing sympathetic critique of industrial ecology by focusing on the key problems and dilemmas that arise in the course of developing eco-industrial parks, drawing upon empirical work conducted in the USA. The paper draws upon both an extensive survey of EIPs and in-depth interviews conducted with a range of stakeholders at ten US sites. As the paper reveals, EIPs in the USA are in their early stages and likewise their contribution to both economic development and environmental policy, let alone social policies, is complicated and inchoate. The empirical material reveals that key features of industrial ecology such as inter-firm networking and collaboration in the form of materials interchange and energy cascading are either absent or in the early planning stages. In each of the ten cases what is emerging is a form of EIP partly determined by the geographic setting and broader economic realities of the locality. While collaborative behaviour between firms is central to EIP development if the potential benefits of industrial ecology are to be realised, it is important to realise that such behaviour is difficult to develop from scratch through policy intervention. In conclusion, the paper suggests that expectations must be realistic for the community and location in question. As part of that realism, EIP projects must be designed to allow for a gradual approach, and each phase needs to be financially viable.  相似文献   
48.
Sequential Factor Analysis (seqFA) is presented here as an enhanced alternative to multivariate factorial techniques including robust and classical Factor Analysis (FA) or Principal Component Analysis (PCA). A geochemical data set of 145 sediment samples from very heterogeneous, mainly riverine, deposits of the Rhine-Meuse delta (The Netherlands) analyzed for 27 bulk parameters was used as a test case. The innovative approach explicitly addresses the priority issues when performing PCA or FA: heterogeneity and overall integrity of the data, the number of factors to be extracted, and which optimum minimal set of key variables to be included in the model. The stepwise decision process is based on quantitative and objectively derived statistical criteria, yet also permitting arguments based on geochemical expertize. The results show that seqFA, preferably in combination with robust methods, yields a highly consistent factor model, and is favorable over classical methods when dealing with heterogeneous data sets. It optimizes rotation of the factors, and allows the extraction of less distinct factors supported by only a few variables, thus uncovering additional geochemical processes and properties that would easily be missed with other approaches. The identification of key variables simplifies the geochemical interpretation of the factors, and greatly facilitates the construction of a geochemical conceptual model. For the case of the fluvial deposits, the conceptual model effectively describes their bulk chemical variation in terms of a limited number of governing processes.  相似文献   
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