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131.
Sven Fuchs Magdalena Thöni Maria Christina McAlpin Urs Gruber Michael Bründl 《Natural Hazards》2007,41(1):113-129
This paper demonstrates the application of cost effectiveness analysis and cost benefit analysis to alternative avalanche
risk reduction strategies in Davos, Switzerland. The advantages as well as limitations of such analysis for natural hazards
planning are discussed with respect to 16 avalanche risk reduction strategies. Scenarios include risk reduction measures that
represent the main approaches to natural hazards planning in Switzerland, such as technical, organisational, and land use
planning measures. The methodologies used outline how concepts and techniques from risk analysis, hazard mapping, Geographic
Information System, and economics can be interdisciplinary combined. The results suggest important considerations, such as
possible sources of uncertainty due to different choices in the calculation of cost effectiveness ratio and net present value.
Given the parameters and assumptions, it seems as if the current approach to avalanche risk reduction in the study area approximates
to economic and cost efficiency and serves the aim of reducing risk to human fatalities. 相似文献
132.
Based on the correlation between discharge and carbonate content of the suspended load of the River Rhine, Germany, a systematic geochemical, mineralogical and granulometric study was carried out to verify whether this geochemical signal is transferred to floodplain deposits and in what way these sediments and their chemostratigraphic characterization can be used as a tool for the reconstruction of the river flood history. The analysis of the time resolved changes in the composition of particulate matter during a flood event revealed that the increase of carbonate content (represented by CaO, Sr) with discharge was coupled to a simultaneous decrease in the relative amount of siliciclastics (K2O, Rb). The association of these two groups of diametrical parameters with specific grain size fractions (carbonates with 40–200 μm; siliciclastics with >200 μm) were found to be slightly shifted relative to each other and showed different gradients during the surging and fading flood wave. This, together with the covariance of elements pertaining to minerals with different density (e.g., carbonate and heavy minerals) suggests a chemical response to the changes in discharge, which is controlled primarily by hydraulic equivalence rather than grain size. There is also a time lag between the amount of suspended load and discharge, with a maximum in suspended load shortly after the peak discharge, when the flood has already started to abate. The flood plain sediments have similar composition to the suspended load, suggesting the direct transfer of the geochemical flood signal to the floodplain sediments. 相似文献
133.
Despite the long tradition of technical mitigation on a catchment scale in European mountain regions, losses due to mountain
hazards are still considerably high in number and monetary loss. Therefore, the concept of technical mitigation had been supplemented
by land-use planning and, more recently, local structural protection. Local structural protection includes measures directly
implemented at or adjacent to endangered objects, and has proven to be particularly cost-effective with respect to integral
risk management strategies. However, the effect of local structural protection in reducing the vulnerability of elements at
risk, and the associated consequences with respect to a reduction of structural vulnerability have not been quantified so
far. Moreover, there is a particular gap in quantifying the expenditures necessary for local structural protection measures.
Therefore, a prototype of residential building adapted to mountain hazards is presented in this study. This prototype is equipped
with various constructional elements to resist the incurring impact forces, i.e., of fluvial sediment transport and of snow
avalanches. According to possible design loads emerging from these hazard processes, the constructive design necessary is
presented, and the amount of additional costs required for such an adaptation is presented. By comparing these costs with
quantitative loss data it is shown that adapted building design is particularly effective to reduce the consequences of low-magnitude,
high-frequency events in mountain regions. 相似文献
134.
Influence of the Po River runoff on the bacterioplankton community along trophic and salinity gradients in the Northern Adriatic Sea 下载免费PDF全文
Ilaria Pizzetti Giuliano Lupini Fabrizio Bernardi Aubry Francesco Acri Bernhard M. Fuchs Stefano Fazi 《Marine Ecology》2016,37(6):1386-1397
The Po River runoff strongly affects the oceanographic and ecological characteristics of the Northern Adriatic Sea. Catalysed reported deposition ‐ fluorescence in situ hybridization (CARD‐FISH) analysis was employed to assess how the composition of the coastal bacterioplankton community is influenced by the river runoff in two different seasons (spring and autumn). Samples were collected from the water column along a coastal–offshore transect in the Northern Adriatic Sea at different depths. Four clone libraries were then constructed from coastal (0 m) and offshore waters (?65 m). Higher abundances of bacteria were recorded in coastal waters as compared with the offshore samples. This result was mainly due to the trophic state of the water column, and it was related to salinity. Particularly, Actinobacteria and Gammaproteobacteria were affected by the riverine inputs, whereas Bacteroidetes and Alphaproteobacteria showed only minor responses. This was particularly clear in the autumn sample, in which a clear difference between the coastal and the offshore samples was found due to a strong influence of the less saline river water with high nutrient concentrations. Analysis of 205 partial length 16S rRNA gene sequences indicated a high diversity with the dominance of Alphaproteobacteria, Bacteroidetes and Gammaproteobacteria mainly affiliated to coastal and marine bacterioplankton clades. Actinobacteria were also detected and, together with Gammaproteobacteria, strongly follow the freshwater intrusion. Overall, our results indicate that the seasonal difference in the Po River discharge greatly affects the bacterioplankton community. In spring we observed a smooth transition from coastal to open‐sea conditions owing to the more superficial freshwater plume. In autumn the deeper freshwater intrusion in the coastal site and thermal stratification offshore resulted in a marked difference between the coastal and offshore microbial communities. 相似文献
135.
H. Fuchs 《Astronomische Nachrichten》1988,309(4):237-238
Our recent Lagrangian approach to the equations of motion for test particles with internal structure can be enlarged to the laws of motion for interacting particles, at least in principle. As an example we consider the interaction of point particles endowed with a pole-dipole structure of the non-abelian charge. 相似文献
136.
H. Fuchs 《Astronomische Nachrichten》1986,307(5):281-283
The equations of motion for test particles with internal structure are derived from a general Lagrange principle. The internal structure of the particles is described by sets of unspecified geometric objects, which transform homogeneously both under coordinate and under gauge transformations. Most of the Lagrangian approaches known in the literature are special cases of our general formalism. 相似文献