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Learning about learning: lessons from public engagement and deliberation on urban river restoration 总被引:1,自引:0,他引:1
JUDITH PETTS 《The Geographical journal》2007,173(4):300-311
This paper provides a new discussion of how people learn through deliberative processes, drawing upon empirical analysis of a novel public engagement process for urban river restoration. Such critical evaluation is rare and yet will be crucial to both theoretical development and learning about engagement practice, not least in a policy area subject to strong regulatory drivers for public participation. The analysis supports two important learning mechanisms – the use of 'gatekeepers' of knowledge, interests and values, and the privileging of narrative. It provides new evidence of instrumental and communicative learning about shared priorities and criteria for effective river restoration that evolved through the deliberative process and directly informed the restoration scheme. It is important to question whether and how such site or context-specific learning might inform other restoration schemes. Finally, the paper questions the often ignored issue of expert learning, not least the issue of the link between individual and organizational learning. 相似文献
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Abstract: Landslide research at the British Geological Survey (BGS) is carried out through a number of activities, including surveying, database development and real-time monitoring of landslides. Landslide mapping across the UK has been carried out since BGS started geological mapping in 1835. Today, BGS geologists use a combination of remote sensing and ground-based investigations to survey landslides. The development of waterproof tablet computers (BGS·SIGMAmobile), with inbuilt GPS and GIS for field data capture provides an accurate and rapid mapping methodology for field surveys. Regional and national mapping of landslides is carried out in conjunction with site-specific monitoring, using terrestrial LiDAR and differential GPS technologies, which BGS has successfully developed for this application. In addition to surface monitoring, BGS is currently developing geophysical ground-imaging systems for landslide monitoring, which provide real-time information on subsurface changes prior to failure events. BGS’s mapping and monitoring activities directly feed into the BGS National Landslide Database, the most extensive source of information on landslides in Great Britain. It currently holds over 14?000 records of landslide events. By combining BGS’s corporate datasets with expert knowledge, BGS has developed a landslide hazard assessment tool, GeoSure, which provides information on the relative landslide hazard susceptibility at national scale. 相似文献
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Hydrothermal experiments with primary detrital components of feldspathic sands (orthoclase, albite, quartz, and calcite) were conducted to simulate possible diagenetic changes in geosynclinal sedimentary accumulations and the geothermal reservoir of the Imperial Valley area, California. Phyllosilicate and zeolite mineralization was produced at 200°C and 1 Kb Ph2o and at 300°C and 1 and 3 Kb Ph2o. Scanning electron microscope examination of the detrital grains shows the development of authigenic minerals and solution features. Phyllosilicate development occurred as dense surface coatings on orthoclase crystals in concentrated brines and as scattered grain clusters in dilute brines. Cation concentration is considered to be a controlling factor in phyllosilicate formation and growth. During formation the phyllosilicate crystals appear to utilize the surficial feldspar lattice structure as a preferred growth site. Electron diffraction studies indicate the crystals are a 1 Md mica similar to illite. Initial phyllosilicate formation occurs principally on orthoclase in systems containing this mineral, but is disseminated on other mineral surfaces in systems without orthoclase. This experimental development of authigenetic illite via the destruction of potassium feldspar may offer a potential mechanism to help explain the resulting mineralogy of diagenetic processes occurring in natural sediments such as in feldspathic sands and argillaceous sediments. 相似文献
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ALESSANDRA SPADAFORA EDOARDO PERRI† JUDITH A. MCKENZIE CRISÓGONO VASCONCELOS Associate Editor: Gert-Jan Reichart 《Sedimentology》2010,57(1):27-40
Modern Ca:Mg carbonate stromatolites form in association with the microbial mat in the hypersaline coastal lagoon, Lagoa Vermelha (Brazil). The stromatolites, although showing diversified fabrics characterized by thin or crude lamination and/or thrombolitic clotting, exhibit a pervasive peloidal microfabric. The peloidal texture consists of dark, micritic aggregates of very high‐Mg calcite and/or Ca dolomite formed by an iso‐oriented assemblage of sub‐micron trigonal polyhedrons and organic matter. Limpid acicular crystals of aragonite arranged in spherulites surround these aggregates. Unlike the aragonite crystals, organic matter is present consistently in the dark, micritic carbonate comprising the peloids. This organic matter is observed as sub‐micron flat and filamentous mucus‐like structures inside the interspaces of the high‐Mg calcite and Ca dolomite crystals and is interpreted as the remains of degraded extracellular polymeric substances. Moreover, many fossilized bacterial cells are associated strictly with both carbonate phases. These cells consist mainly of 0·2 to 4 μm in diameter, sub‐spherical, rod‐like and filamentous forms, isolated or in colony‐like clusters. The co‐existence of fossil extracellular polymeric substances and bacterial bodies, associated with the polyhedrons of Ca:Mg carbonate, implies that the organic matter and microbial metabolism played a fundamental role in the precipitation of the minerals that form the peloids. By contrast, the lack of extracellular polymeric substances in the aragonitic phase indicates an additional precipitation mechanism. The complex processes that induce mineral precipitation in the modern Lagoa Vermelha microbial mat appear to be recorded in the studied lithified stromatolites. Sub‐micron polyhedral crystal formation of high‐Mg calcite and/or Ca dolomite results from the coalescence of carbonate nanoglobules around degraded organic matter nuclei. Sub‐micron polyhedral crystals aggregate to form larger ovoidal crystals that constitute peloids. Subsequent precipitation of aragonitic spherulites around peloids occurs as micro‐environmental water conditions around the peloids change. 相似文献
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A Barometer for Garnet Amphibolites and Garnet Granulites 总被引:5,自引:5,他引:5
new barometer based on the equilibrium:
has been calibrated with experiments conducted in the piston-cylinderapparatus. Reversed equilibria have been obtained using well-calibrated2-54 cm NaCl furnace assemblies, Ag80Pd20capsules withfO2 bufferedat or near iron-wustite. The equilibrium is located between10.610.8,12.012.2, 13.213.4 and 14.214.4kb, at 800, 900, 1000, and 1100?C, respectively. The barometer is applicable in both garnet-bearing amphibolitesand granulites. Its greatest potential is in garnet amphiboliteswherein multi-variant amphibole-bearing mineral assemblagesdo not define pressure and few, if any, well-calibrated barometersare available. Application of the garnet-rutile-ilmenite-plagioclase-quartzbarometer in amphibolite and granulite terranes yields geologicallyreasonable pressures that are in agreement with other well-calibratedbarometers in those terranes where comparisons can be made. 相似文献