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561.
Non Okumura Sebastiaan N. Jonkman Miguel Esteban Bas Hofland Tomoya Shibayama 《Natural Hazards》2017,88(3):1451-1472
This paper presents a methodology for tsunami risk assessment, which was applied to a case study in Kamakura, Japan. This methodology was developed in order to evaluate the effectiveness of a risk-reducing system against such hazards, also aiming to demonstrate that a risk assessment is possible for these episodic events. The tsunami risk assessment follows these general steps: (1) determination of the probability of flooding, (2) calculation of flood scenarios, (3) assessment of the consequences and (4) integration into a risk number or graph. The probability of flooding was approximated based on the data provided by local institutes, and the flood scenarios were modeled in 1D using the Simulating WAves till SHore model. Results showed that a tsunami in Kamakura can result in thousands of casualties. Interventions such as improvements in evacuation systems, which would directly reduce the number of casualties, would have a large influence in risk reduction. Although this method has its limits and constraints, it illustrates the value it can add to existing tsunami risk management in Japan. 相似文献
562.
Rural gentrification in Catalonia, Spain: A case study of migration, social change and conflicts in the Empordanet area 总被引:4,自引:0,他引:4
Miguel Solana-Solana 《Geoforum》2010,41(3):508-517
The intensity of rural depopulation in Catalonia has diminished since the 1980s. New population growth patterns are occurring in rural areas, basically due to immigration. Although there has been a certain awareness of the magnitude of this process and its territorial distribution, little is known about the protagonists in this immigration and the impact on rural municipalities. Results are presented from a study of the immigration process in a group of rural inland municipalities close to the Costa Brava, a Mediterranean coastal region with extensive tourism. The great beauty of the landscape and the existence of housing stock that is being abandoned but remains desirable have led to a population influx from Catalonia’s large urban areas, especially Barcelona, purchasing these homes as a primary or secondary residence.This has led to rehabilitation of the housing stock, but also to higher housing prices and the resulting exodus of the young local population that cannot afford them; a potential source of conflict between the local population and the newcomers. The study is based on census data and statistical records, as well as extensive fieldwork, including interviews with local residents, newcomers and key informants. 相似文献
563.
In ordinary chondrites tungsten displays both lithophile and siderophile characteristics. Its concentration in the metal phase is positively correlated with petrologic type, and with the distribution coefficientKD =W in metal/W in silicates plus troilite. The oxidation-reduction reactions involved are temperature-dependent and the recrystallization temperature recorded on the basis of the partition of W between coexisting metal and silicate plus troilite fractions are950° ± 100°C for equilibrated chondrites (types 5 and 6), and800° ± 50°C for type 4, while Shaw (L7) records the highest recrystallization temperature (>1200°C).The different metallic content of the three groups of ordinary chondrites has been attributed to a metal-silicate fractionation process. Such a process appears to have fractionated W and Ir, but not W and Fe as these elements were partly oxidized when the fractionation process took place. 相似文献
564.
Christian Gonzalo Domínguez Miguel Francisco García Vera Cédric Chaumont Julien Tournebize Marcos Villacís Noemi d'Ozouville Sophie Violette 《水文研究》2017,31(18):3191-3205
With changes in climate looming, quantifying often‐overlooked components of the canopy water budget, such as cloud water interception (CWI), is increasingly important. Commonly, CWI quantification requires detailed continuous measurements, which is extremely challenging, especially when throughfall is included. In this study, we propose a simplified approach to estimate CWI using the Rutter‐type interception model, where CWI inputs in the canopy vegetation are proportional to fog interception measured by an artificial fog gauge. The model requires the continuous acquisition of meteorological variables as input and calibration datasets. Throughfall measurements below the forest are used only for calibration and validation of the model; thus, CWI estimates can be provided even after the cessation of throughfall monitoring. This approach provides an indirect and undemanding way to quantify CWI by vegetation and allows the identification of its controlling factors, which could be useful to the comparison of CWI in contrasting land covers. The method is applied on a 2‐year dataset collected in an endemic highland forest of San Cristobal Island (Galapagos). Our results show that CWI reaches 21% ± 6% of the total water input during the first year, and 9% ± 2% during the second one. These values represent 32% ± 10% and 17% ± 5% of water inputs during the cool foggy season of the first and second year, respectively. The difference between seasons is attributed to a lower fog liquid water during the second season. 相似文献
565.
Francisco Torres-Avilés Miguel A. Martinez-Beneito 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(1):131-141
Spatio-temporal disease mapping can be viewed as a multivariate disease mapping problem with a given order of the geographic patterns to be studied. As a consequence, some of the techniques in multivariate literature could also be used to build spatio-temporal models. In this paper we propose using the smoothed ANOVA multivariate model for spatio-temporal problems. Under our approach the time trend for each geographic unit is modeled parametrically, projecting it on a preset orthogonal basis of functions (the contrasts in the smoothed ANOVA nomenclature), while the coefficients of these projections are considered to be spatially dependent random effects. Despite the parametric temporal nature of our proposal, we show with both simulated and real datasets that it may be as flexible as other spatio-temporal smoothing models proposed in the literature and may model spatio-temporal data with several sources of variability. 相似文献
566.
567.
In this paper the Marine Fish Community Index (MFCI) for the assessment of ecological status of marine environment is proposed. The MFCI was divided into 4 typologies: Rocky subtidal; shallow, intermediate and deep soft-bottoms. Based on the typical community associated to each typology and the DPSIR analysis performed, a set of metrics were selected and tested through a multiple correlation matrix (Pearson’s coefficient) and the core ones included in the index. The MFCI was applied in all typologies and the scores obtained with each metric were analyzed. In order to test the robustness of the MFCI the final ecological value of each zone was recalculated by removing successively one metric at a time. The MFCI showed a sensitive and robust response in the ecological status assessment. Since it incorporates both functional and structural community information, the MFCI can be useful in the context of the Marine Strategy Framework Directive as well as in other contexts of conservation and sustainable management of the marine environment. 相似文献
568.
Organic composition of atmospheric urban aerosol: Variations and sources of aliphatic and polycyclic aromatic hydrocarbons 总被引:1,自引:0,他引:1
Miguel A. Barrero Mazquiarn Lourdes Cantn Ortiz de Pinedo 《Atmospheric Research》2007,85(3-4):288-299
The non-polar organic composition of airborne particulate matter was analysed over a two year period in an urban area under oceanic climate conditions (Errenteria, Basque Country, Spain). In addition, the distribution of polycyclic aromatic hydrocarbons (PAH) among different aerosol particle sizes was determined. Clues as to the origin of various particle types were gained by using scanning electron microscopy to view the morphology of the particulates in each size fraction. Samples were collected on glass fibre filters and analysed by means of soxhlet extraction and gas chromatography (either with a flame ionization detector or coupled to a mass spectrometry). In general, total PAH levels were moderate (0.96–50 ng m− 3) as compared to other studies conducted in Europe, and showed clear seasonal variation with maxima in winter and minima in summer. Vehicular traffic was identified as a major source of PAHs in the study area. Regarding particle size, a bimodal distribution was observed. The large sized particles exhibited an apparent seasonal variation with higher concentrations in winter than in summer. The dependences between particle size, PAH distribution and meteorological variables were studied with multivariate statistics. Three main sources of organic compounds were identified: combustion, vegetation, and atmospheric oxidation. 相似文献
569.
This paper investigates the equity implications of marketing ecosystem services in protected areas and rural communities. We use a three-tiered equity framework to analyse four distinct efforts to commercialise watershed recharge and carbon dioxide fixation by forests in Meso-America. We show that project development and participation are strongly mediated by organisational networks, as well as existing rights of access over land and forest resources. We demonstrate that procedural fairness diverges strongly when initiatives are implemented in protected areas or in rural communities. While in the former reserve managers and intermediaries concentrate all decision-making power, initiatives working with rural communities are able to integrate more significantly service providers in management decisions. Marketing ecosystem services in protected areas contributes to reduce expenditure rates for protected area management, but also results in less equitable outcomes, as rural communities and forest resource users become excluded from receiving sustained development benefits. When ecosystem services are commercialised by rural farmers, payments do not cover opportunity costs but act as a significant incentive for participation in most cases. Ecosystem service providers also benefit from complementary project activities, such as forest management training and agricultural extension support. We argue that limited economic impact and existing inequities in decision-making and outcomes can be explained by problems of institutional design, in particular the inability of markets and payments for ecosystem services to account for context-related factors, such as property rights. 相似文献
570.
The present paper analyses predation patterns, of Percichthys trucha and salmonid fish upon Galaxias maculatus in five lakes of northern Patagonia with differing community and environmental characteristics. Tank experiments were performed to evaluate relative efficiency of native and exotic predators of G. maculatus under treatments with and without cover (aquatic vegetation). Important differences were found between predators with regards to distribution and consumption of G. maculatus. Salmonids are more efficient than P. trucha in consuming G. maculatus in deep environments with scarcely vegetation; in contrast to native species they frequently use the pelagic environment. Although pelagic habitat might have served in the past as a refuge from native predators in the past, G maculatus now experiences intense predation in the pelagic zone by exotic salmonids. It is suggested that the widespread distribution of G. maculatus in Patagonian lakes may have facilitated the success of salmonids throughout Patagonia. 相似文献