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Anna Scolobig Nadejda Komendantova Anthony Patt Charlotte Vinchon Daniel Monfort-Climent Mendy Begoubou-Valerius Paolo Gasparini Angela Di Ruocco 《Natural Hazards》2014,73(3):1523-1545
Technical and institutional capacities are strongly related and must be jointly developed to guarantee effective natural risk governance. Indeed, the available technical solutions and decision support tools influence the development of institutional frameworks and disaster policies. This paper analyses technical and institutional capacities, by providing a comparative evaluation of governance systems in Italy and France. The focus is on two case studies: Naples and Guadeloupe. Both areas are exposed to multiple hazards, including earthquakes, volcanic eruptions, landslides, floods, tsunamis, fires, cyclones, and marine inundations Cascade and conjoint effects such as seismic swarms triggered by volcanic activity have also been taken into account. The research design is based on a documentary analysis of laws and policy documents informed by semi-structured interviews and focus groups with stakeholders at the local level. This leads to the identification of three sets of governance characteristics that cover the key issues of: (1) stakeholders and governance level; (2) decision support tools and mitigation measures; and (3) stakeholder cooperation and communication. The results provide an overview of the similarities and differences as well as the strengths and weaknesses of the governance systems across risks. Both case studies have developed adequate decision support tools for most of the hazards of concern. Warning systems, and the assessment of hazards and exposure are the main strengths. While technical/scientific capacities are very well developed, the main weaknesses involve the interagency communication and cooperation, and the use and dissemination of scientific knowledge when developing policies and practices. The consequences for multi-risk governance are outlined in the discussion. 相似文献
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Victor R. Baker 《Environmental Geology》1975,1(2):75-88
A cooperative program in urban geology between the city of Boulder, Colorado, and the Department of Geological Sciences, University of Colorado, has been in effect since late 1969. The principal geological problems in the rapidly growing urban environment of Boulder include:
- Swelling clays in the Pierre Shale have been related to foundation failure, pavement heaving, and landsliding on hillslopes.
- Colluvium and ancient landslides have been made unstable by removal of support, by loading with buildings or fill, and by increases over natural moisture contents through lawn watering and septic-tank seepage.
- Flooding on high-gradient mountain streams has been caused by sedimentation induced by the constriction of natural channels through urban development. In May, 1969, Bear Canyon Creek overflowed its banks with a discharge of less than one-fifth its design capacity. Flooding was caused by coarse bedload deposited upstream from a culvert.
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Augustine Tanle 《GeoJournal》2014,79(5):577-590
In Ghana, studies on migration and livelihoods are mostly limited to migrants’ places of origin. This paper therefore assesses livelihood status of permanent migrants resident in the Obuasi Municipality who hail from the northern parts of Ghana. The instrument used was a survey questionnaire and the respondents were both migrants and indigenes aged 18 years and above. The findings showed no significant differences between migrants and indigenes in ownership of assets and consumer durable goods and housing quality. However, the indigenes earned relatively higher than the migrants due to access to various forms of capital and the influence of institutional structures and processes. But to the migrants, their livelihood status has improved since they have built houses, educated their children, remitted relations at home and have acquired some consumer durable goods. Improvement in the livelihood status of migrants could induce further north–south migration. There is therefore the need for government and other stakeholders to bridge the gap of unequal socio-economic development between the northern and southern parts of the country. 相似文献
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A thermochemical data base for phases in the system Fe-Mg-Si-O at high pressures up to 300 kbar is established by supplementing the available calorimetric data with data calculated from experimental high pressure synthesis studies. Phases included in the data base are the SiO2 polymorphs, rock salt solid solutions (Fe-Mg-O), Fe2O3, Fe3O4, (Mg, Fe)2SiO4 olivine, spinel, modified spinel and (Mg, Fe)SiO3 perovskite and pyroxene. Phases not included are the MgSiO3-ilmenite and -garnet. Fe-Mg solution properties of olivine, spinel, perovskite and wustite (rock salt) are estimated. The wüstite solid solution has been modeled as a nonideal solution of three end members; FeO, FeO1.5 and MgO. The new data base is made consistent with most of the available information on high pressure phase studies. The data base is useful in generating phase diagrams of various different compositions for the purpose of planning new experiments and analysing existing phase synthesis data. 相似文献
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The availability of multiple history matched models is essential for proper handling of uncertainty in determining the optimal development of producing hydrocarbon fields. The ensemble Kalman Filter in particular is becoming recognized as an efficient method for quantitative conditioning of multiple models to history data. It is known, however, that the ensemble Kalman Filter (EnKF) may have problems with finding solutions in history matching cases that are highly nonlinear and involve very large numbers of data, such is typical when time-lapse seismic surveys are available. Recently, a parameterization of seismic anomalies due to saturation effects was proposed in terms of arrival times of fronts that reduces both nonlinearity and the effective number of data. A disadvantage of the parameterization in terms of arrival times is that it requires simulation of models beyond the update time. An alternative distance parameterization is proposed here for flood fronts, or more generally, for isolines of arbitrary seismic attributes representing a front that removes the need for additional simulation time. An accurate fast marching method for solution of the Eikonal equation in Cartesian grids is used to calculate distances between observed and simulated fronts, which are used as innovations in the EnKF. Experiments are presented that demonstrate the functioning of the method in synthetic 2D and realistic 3D cases. Results are compared with those resulting from use of saturation data, as they could potentially be inverted from seismic data, with and without localization. The proposed algorithm significantly reduces the number of data while still capturing the essential information. It furthermore removes the need for seismic inversion when the oil-water front is only identified, and it produces a more favorable distribution of simulated data, leading to a very efficient and improved functioning of the EnKF. 相似文献
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F. Lindenmaier R. Miller J. Fenner G. Christelis H. G. Dill T. Himmelsbach S. Kaufhold C. Lohe M. Quinger F. Schildknecht G. Symons A. Walzer B. van Wyk 《Hydrogeology Journal》2014,22(6):1307-1328
An exploration strategy for groundwater was established and followed in the northern Namibian Cuvelai-Etosha Basin (CEB). The data derived from transient electromagnetics, rotary-drilling, coring and sample investigation were used to refine stratigraphy and hydrostratigraphy, and to develop a 3D map of aquifers within the Cubango Megafan. The results have delineated three major aquifers. The newly found, deep-seated Ohangwena II Aquifer (KOH-2) has the potential of providing significant additional water to the water supply of northern Namibia and Angola. While near-surface aquifers carry predominantly brackish water, freshwater in the deep-seated aquifer is further extended and features good hydraulic properties. To date, only a small part of the hydrogeological potential of arid CEB has been explored and an extension of exploration is needed, including southern Angola. The combination of structural, sedimentological and hydrogeological approaches greatly advanced both the geological and hydrogeological understanding. With regard to the deep-seated aquifer, strict measures need to be applied to ensure that the water in the KOH-2 reservoir is exploited sustainably. Water control areas need to be established to ensure long-term preservation of this newly explored aquifer. 相似文献
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Barbara Louise Endemaño Walker David López-Carr Cheryl Chen Kitty Currier 《GeoJournal》2014,79(6):705-719
Pacific Islands are considered among the most vulnerable geographies and societies to the effects of climate change and variability (CCV). This study addresses the mismatch between global climate change narratives and local perceptions of environmental change in Moorea, French Polynesia. This study builds on CCV risk perception and adaptation research by analyzing how temporal and historical socio-economic, cultural, political, and ecological contexts shape local perceptions of environmental change among a sample of environmental stakeholders in Moorea. The data were collected prior to the widespread global narrative and social amplification of climate change risk and its particular impact on islands. As such, they offer an important portrait of environmental perceptions in French Polynesia prior to the influence of a circumscribed climate change narrative, which has since come to shape government and NGO responses to environmental change in the Pacific Island Countries and Territories. The data presented in this paper illustrate that perceptions of drivers and effects of environmental change and risk in Moorea are embedded in larger social processes of political economy and ecology, particularly related to contemporary environmental politics, contextualized within the histories of colonialism and tourism-led economic development. Integrating the complexity of local environmental risk perceptions into CCV policy will help to avoid maladaptation, social movements against CCV planning, and may help maximize government and donor investments. 相似文献
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The data published earlier on zircon and sphene fission track ages and annealing are discussed in the light of different etching conditions used for age determination and annealing experiments in order to explain the age discordances of some zircon and sphene pairs, as well as numerous closing temperatures obtained for individual minerals. Using the new set of simple etching conditions, zircon (KOH melt) and sphene (HF+HCl), the annealing experiments indicate that tracks in sphene are annealed more easily than in zircon. The closing temperature of zircon and sphene have been calculated at 300° and 250° C respectively. The study reveals that both the fission track age and the closing temperature of a mineral can vary considerably if different etchants are used. For different etching conditions the closing temperatures (T) of sphene have the following order: T NaOH> T HF+HCl+HNO3+H2O> THF+HCl>THCl. An alternative method can be used to obtain thermal histories of rocks by selectively applying various etchants on the same mineral. 相似文献
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浅析GIS通信本地网管理系统的建设 总被引：15，自引：3，他引：12
通信本地网是我国公用通信网的重要组成部分, 其管理工作以往一直是由人工完成的.要做好通信本地网的管理与维护工作, 必须采用先进的技术建立GIS通信本地网管理系统, 实现电信公司通信本地网的规划设计、工程施工、运行维护管理与统计分析等的计算机化, 为各相关部门提供多专业、多层次、多目标的综合服务.详细介绍了通信本地网管理的现状, 从基于管理、人员、电信发展以及新技术的发展等方面进行分析, 阐述了建立GIS通信本地网管理系统的必要性, 详细介绍了在建设系统时需要考虑的各种技术问题: 系统设计原则、系统应该遵照的标准、涵盖的资源、系统主要功能、数据管理模式、数据库选型、硬件选型和GIS平台的选择等.还介绍了基于MAPGIS平台开发的通信网络地理信息系统在全国的应用情况. 相似文献
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Distribution patterns of suspended sediments and sea surface temperatures in, Mobile Bay were derived from algorithms using digital data from the visible, near infrared, and infrared channels of the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-TIROS-N satellite. Closely spaced AVHRR scenes for January 20, 24, and 29, 1982, were compared with available environmental information taken during the same period. A complex interaction between river discharge, winds, and astronomical tides controlled the distribution patterns of suspended sediments. These same variables, coupled with air temperatures, also governed the distribution patterns of sea surface temperatures. 相似文献
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B. Marler 《Physics and Chemistry of Minerals》1988,16(3):286-290
Five different refraction formulas were applied to SiO2 polymorphs in order to determine the most suitable refractive index-density relation. 13 SiO2 polymorphs with topological different tetrahedral frameworks are used in this study including eight new low density SiO2 polymorphs — so called “guest free porosils”. These SiO2 polymorphs cover a density range from 1.76 to 2.92 g/cm3. The mean refractive indices (ovn) of the porosils have been determined by the immersion method, the densities (ρ) were calculated from the unit cell parameters. Assuming the polarizability (α) of all SiO2 polymorphs to be constant the general refractivity formula $$\{ 2\overline {11} 0\} \langle 0001\rangle $$ turned out to be the most suitable for SiO2 polymorphs. Regression analysis yields an electronic overlap parameter b=1.2(1). 相似文献
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This exploratory study contributes to our knowledge about the relationships between interpersonal communication sources and risk perception regarding natural hazards. Survey data (N?=?186) from a small village in northwest China was used, and the correlations between eight types of interpersonal communication sources related to disaster risk reduction and the perceived severity and perceived likelihood of occurrence of eight types of natural hazards were explored. Past studies have suggested that interpersonal communication sources are more likely to influence individuals in their perceived severity of natural hazards than in their perceived likelihood of occurrence. The results of this study moderately corroborate this finding. The results indicated that different sources have different relationships to risk perception, as positive correlations were found between obtaining information via certain trained science professionals (science teachers, emergency responders, scientific experts) and certain natural hazard risk perceptions, while negative relationships were found between obtaining information via certain personal contacts (other villagers and relatives and friends) and certain natural hazard risk perceptions. However, the strength of these relationships was weak (??0.197?≥?r?≤? 0.245). Age showed statically significant correlations with the perceived severity of most of the natural hazards. Studies with more representative samples and controls for theoretical factors are needed to better understand how interpersonal communication sources affect individuals' natural hazard risk perceptions. 相似文献
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D. K. Verma S. H. Hasan D. Ranjan R. M. Banik 《International Journal of Environmental Science and Technology》2014,11(7):1927-1938
Phanerochaete chrysosporium, a white rot basidiomycete, was immobilized over Luffa cylindrica sponge discs, treated with 0.1 N HCl and its potentiality for the removal of hexavalent chromium [Cr(VI)] from water was investigated in both batch and in up-flow fixed-bed bioreactor. The acid treatment of biomass increased the uptake capacity and percentage removal of Cr(VI) from 33.5 to 46.5 mg g?1 and 67 to 92 %, respectively. Maximum uptake of Cr(VI) was achieved at pH 2, temperature 40 °C after 100 min of contact time. The Cr(VI) sorption on the biomass was better explained by Langmuir isotherm. Thermodynamic studies indicated that the process was spontaneous and endothermic. Sorption kinetic study showed that pseudo-second-order model best correlates the Cr(VI) sorption on the biomass as compare to pseudo-first-order kinetic model. The performance of fixed-bed bioreactor was evaluated at different bed heights (5, 15 and 25 cm) and flow rates (1.66, 4.98 and 8.33 mL min?1) by using bed depth service time model. Response surface methodology statistical method was applied for optimizing the process parameters. FTIR analysis showed that amino groups were mainly involved in adsorption of Cr(VI). 相似文献
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The equilibrium position of the reaction $$\begin{gathered} 1.5 KAlSi_3 O_8 + HCl = 0.5 KAl_3 Si_3 O_{10} (OH)_2 \hfill \\ + 3SiO_2 + KCl \hfill \\ \end{gathered} $$ has been located at 1 and 2 kb pressure and temperatures between 600° and 670° C using the Ag-AgCl buffer. These data can be combined with information on the dissociation of KC1, HC1 and H2O to determine species abundances in supercritical aqueous fluids in equilibrium with muscovite — K-feldspar — quartz assemblages. Chloride species become increasingly associated with increasingT, increasing total molality, (m tot or \(m_{Cl_{tot} } \) ), and decreasing \(P_{H_2 O} \) . Master variable diagrams indicate that the pH of the solutions may vary from near neutral to quite acid. Published data on the paragonite-albite-quartz reaction and exchange reactions involving feldspars and micas were included to calculate speciation in mica-feldspar-NaCl-KCl-HCl-H2O fluids at 2kb pressure and temperatures between 300° and 600° C. The data are not accurate enough to distinguish different feldspar structural states. Concentration gradients were calculated for individual species between K-feldspar+quartz, muscovite+quartz and andalusite+quartz assemblages at 500° C, 2 kb. Assuming that the proton diffuses most rapidly and that there are no [H+] gradients, the molality of the solution must vary 30-fold, with feldspar+quartz at the more concentrated side. The data on mica-feldspar-chloride equilibria are used to interpret the spacial distribution of micas, feldspar and quartz in microfolds. This distribution can be accounted for by pressure solution, due to the fact that non-hydrostatic pressure affects congruently dissolving minerals, auch as quartz, differently from minerals which dissolve incongruently, such as micas and feldspars. We postulate, that during folding at constant \(P_{H_2 O} \) ,T and \(m_{Cl - } \) , gradients in KC1 and SiO2 are created by stress differences between hinge and limb of a microfold, such that both migrate to the hinge area where quartz precipitates and muscovite is converted to K-felspar, thus accounting for the observed mineral distribution. 相似文献
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Georges Calas Gordon E. Brown Jr. Glenn A. Waychunas Jacqueline Petiau 《Physics and Chemistry of Minerals》1987,15(1):19-29
Selected results of x-ray absorption spectroscopy (XAS) studies of amorphous silicates and minerals are presented in order to show their utility in providing short-and, in certain cases, medium-range structural and bonding information for cations and anions. EXAFS and XANES studies of amorphous silicates are reviewed with the objective of illustrating variations in structural environments of the various types of glass-forming cations, including Si, Al, Na, K, Ca, Ti, Fe, Yb, and U. Al is shown to occur in tetrahedral coordination in all aluminosilicate glasses examined, including peraluminous compositions. The weakly bonded Na and Ca cations are shown to occur in sites with observed coordination numbers (ranging from 6 to 7) and distances similar to those predicted by molecular dynamics simulations. Elements like Ti, which form bonds of intermediate strength, may show some order beyond the first coordination shell at low concentrations in silicate glasses. EXAFS studies of Yb and U in silicate glasses at trace to minor concentration levels provide unique structural information about the environments of these cations. K-edges and XANES of transition element sulfides, third-row tetrahedral oxyanions, and oxygen in minerals are interpreted in terms of band theory or molecular orbital theory. 相似文献