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排序方式: 共有239条查询结果,搜索用时 15 毫秒
191.
Sabine L. Perch-Nielsen 《Climatic change》2010,100(3-4):579-606
The attractiveness of a region for touristic activities depends strongly on the local weather and climate. This paper analyses the vulnerability of the beach tourism sector towards climate change by means of an index approach on a country level. A vulnerability framework for the tourism sector is developed and on its basis, indicators are defined for exposure, sensitivity and adaptive capacity. A transparent index approach, including a robustness analysis with multiple transformation methods and weighting sets, yields an assessment of the overall relative vulnerability of the beach tourism sector in 51 countries. Aggregate results on an annual level are presented as a starting point for a more detailed comparison of countries based on the individual indicators. The important limitations regarding the availability of accurate indicators as well as the concept of vulnerability itself are discussed. Despite these limitations, the present study contributes to integrating the numerous direct as well as indirect effects climate change may have on beach tourism. 相似文献
192.
193.
A multicriteria approach for flood risk mapping exemplified at the Mulde river,Germany 总被引:2,自引:4,他引:2
In this paper we develop a GIS-based multicriteria flood risk assessment and mapping approach. This approach includes flood
risks which are not measured in monetary terms; it shows the spatial distribution of multiple risks, and it is able to deal
with uncertainties in criteria values and to show their influence on the overall flood risk assessment. Additionally, the
approach can be used to show the spatial allocation of the flood effects if risk reduction measures are implemented. The approach
is applied to a pilot study for the River Mulde in Saxony, Germany, heavily affected by the hazardous flood in 2002. Therefore,
a GIS database of economic, social and environmental risk criteria was created. Two different multicriteria decision rules,
a disjunctive and an additive weighting approach, are utilised for an overall flood risk assessment in the area. For implementation,
a software tool (FloodCalc) was developed supporting both, the risk calculation of the single criteria as well as the multicriteria
analysis.
相似文献
Volker MeyerEmail: |
194.
195.
In this paper, we present an approach to modelling multicriteria flood vulnerability which integrates the economic, social
and ecological dimension of risk and coping capacity. We start with an existing multicriteria risk mapping approach. The term
risk is used here in a way that could be called a starting point view, looking at vulnerability without considering coping capacities. We extend this approach by a multicriteria modelling of coping capacities towards an end point view of vulnerability. In doing so, we explore a way to differentiate coping capacity from flood risk in each of the dimensions
of vulnerability. The approach is tested in an urban case study, the city of Leipzig, Germany. Our results show that it is
possible to map multicriteria risks as well as coping capacities and relate them in a simple way. However, a detailed calculation
of end point vulnerability would require more detailed knowledge on the causal relationships between risk and coping capacity criteria
and their relative importance. 相似文献
196.
Sabine Roussel Sylvain Huchette Jacques Clavier Laurent Chauvaud 《Journal of Sea Research》2011,65(2):213-218
The ormer, Haliotis tuberculata is the only European abalone species commercially exploited. The determination of growth and age in the wild is an important tool for fisheries and aquaculture management. However, the ageing technique used in the past in the field is unreliable. The stable oxygen isotope composition (18O/16O) of the shell depends on the temperature and oxygen isotope composition of the ambient sea water. The stable oxygen isotope technique, developed to study paleoclimatological changes in shellfish, was applied to three H. tuberculata specimens collected in north-west Brittany. For the specimens collected, the oxygen isotope ratios of the shell reflected the seasonal cycle in the temperature. From winter-to-winter cycles, estimates of the age and the annual growth increment, ranging from 13 to 55 mm per year were obtained. This study shows that stable oxygen isotopes can be a reliable tool for ageing and growth studies of this abalone species in the wild, and for validating other estimates. 相似文献
197.
Does ratification matter and do major conventions improve safety and decrease pollution in shipping?
This article develops a method to measure the effect of the major international conventions in the area of safety, pollution, search and rescue and work related measures. It further distinguishes between the effect of entry into force and the status of ratification of a convention by its parties. Standard econometric models are used and the analysis is based on a unique dataset of 30 years of monthly data where the models also correct for other factors which can influence safety such as safety inspections and ship economic cycles. The results show a complex picture where the average time between adoption and entry into force was calculated to be 3.1 years. Overall, the more parties ratify a convention, the more likely safety is improved and pollution is decreased although one can detect a certain level of non-compliance. The immediate effect of entry into force presents a mixed picture where most negative effects can be found with legislation in the area of safety management and pollution, followed by technical areas. The effect of legislation in the areas related to working and living conditions and certification and training is smallest. Seasonality can be found with peaks in December and January for all conventions but are less important for pollution. 相似文献
198.
Aurélia Mouret Pierre Anschutz Pascal Lecroart Gwénaëlle Chaillou Christelle Hyacinthe Jonathan Deborde Frans J. Jorissen Bruno Deflandre Sabine Schmidt Jean-Marie Jouanneau 《Geo-Marine Letters》2009,29(3):133-149
Manganese is a major redox reactive element of benthic metabolism. We have built a database of existing knowledge on the benthic
geochemistry of Mn in the Bay of Biscay, in order to comprehensively assess the behaviour of Mn in a variety of environments
during early diagenesis. The database contains vertical profiles of particulate and dissolved Mn species of 59 cores collected
during 17 cruises between 1997 and 2006 at nine stations positioned between 140 and 4,800 m water depths. At all studied stations,
Mn species follow the conventional distribution, where Mn(III,IV) species are enriched in the oxic layer, and dissolved Mn
is present in the anoxic sediments. A minor part of Mn-oxides originates from sedimenting particles. The major part is of
diagenetic origin, and derives from the oxidation of upward-diffusing dissolved Mn(II). Mn-oxide inventories are higher at
the deeper stations than at the shallower ones. This difference cannot be attributed to different sources of sedimenting particles,
but it must depend on sedimentation rate and diagenetic processes. At depth, dissolved Mn(II) concentrations are constant.
This probably reflects equilibrium with an authigenic Mn(II) phase, which is the ultimate phase into which Mn is fossilized.
The Mn content of deeper anoxic sediments is similarly low in all the cores studied, associated with corresponding trends
of Mn content in sedimenting particles of the Bay of Biscay. Bioturbation, rather than redox oscillations, can convey Mn(III,IV)
species downwards into the anoxic sediments where they are reduced, associated with a peak of dissolved Mn. Because dissolved
Mn(II) is re-oxidized when it diffuses towards the oxic layer, the inventory of the diagenetic Mn(III,IV) phase remains at
steady state, especially at stations where the oxic layer is thick. It then becomes possible to calculate the residence time
of diagenetic Mn(III,IV) particles within the oxic layer, using the upward-directed flux of pore water Mn(II). By applying
this residence time to the accumulation of sediments within the oxic layer, we obtain the sediment mass accumulation rate.
The values calculated for the sediments of the Bay of Biscay fit well with accumulation rates obtained from radionuclides
or sediment traps. The method has also been validated with data collected in other marine sedimentary environments.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
199.
Can pharmaceuticals interfere with the synthesis of active androgens in male fish? An in vitro study 总被引:1,自引:0,他引:1
The in vitro interference of fibrate (gemfibrozil, clofibrate, clofibric acid), anti-inflammatory (ibuprofen, diclofenac), and anti-depressive (fluoxetine, fluvoxamine) drugs with key enzymatic activities—C17,20-lyase and CYP11β-involved in the synthesis of active androgens in gonads of male carp have been investigated. Among the tested compounds, fluvoxamine and fluoxetine were the strongest inhibitors of C17,20-lyase and CYP11β enzymes, with IC50s in the range of 321-335 μM and 244-550 μM, respectively. To our knowledge this is the first report on the interaction of pharmaceutical compounds with enzymatic systems involved in the synthesis of oxy-androgens. As oxy-androgens are known to influence spermatogenesis and stimulate reproductive behavior and secondary sexual characteristics in male fish, this work highlights the need for further investigating these endpoints when designing specific in vivo studies to assess the endocrine disruptive effect of pharmaceuticals in fish. 相似文献
200.
Sabine Schmidt Hélène Howa Aurelia Mouret Fabien Lombard Pierre Anschutz Laurent Labeyrie 《Continental Shelf Research》2009,29(8):1044-1052
As a part of the ANR-Forclim experiment, particle mass fluxes and sedimentation processes were investigated on the slope of Aquitanian margin of the Bay of Biscay, between the canyons of Cap-Breton and Cap-Ferret. Interface sediments were collected along a depth transect from 145 to 2000 m; simultaneously a mooring line was deployed at the deepest station (WH, 2000 m) with two traps (800 and 1700 m) for a 16-month period (June 2006–November 2007). 210Pb activities of settling particles and of interface sediments were determined to study transport processes of particles. Sediment and mass accumulation rates, calculated from excess 210Pb profiles in the sediment column, show the expected decreasing trend with depth, as usually observed on margins. Mean particulate mass fluxes at 800 and 1700-m depth at site WH are, respectively, 27 and 70 g m?2 a?1.The 210Pb budget points out events of temporary high lateral input of particles. The comparison of mass and 210Pb fluxes between the water column and the seabed indicates that lateral transport plays an important role in particle accumulation on the Aquitanian margin. Regarding the objectives of the ANR-Forclim program, which aims to improve significantly the interpretation of fossil foraminifera signals, as a proxy for hydrological changes in the North Atlantic ocean, these results highlight advection processes must be considered when interpreting fluxes of foraminifers on the Aquitanian margin. 相似文献