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11.
Gerardo Herrera  Rosa María Mateos  Juan Carlos García-Davalillo  Gilles Grandjean  Eleftheria Poyiadji  Raluca Maftei  Tatiana-Constantina Filipciuc  Mateja Jemec Auflič  Jernej Jež  Laszlo Podolszki  Alessandro Trigila  Carla Iadanza  Hugo Raetzo  Arben Kociu  Maria Przyłucka  Marcin Kułak  Michael Sheehy  Xavier M. Pellicer  Charise McKeown  Graham Ryan  Veronika Kopačková  Michaela Frei  Dirk Kuhn  Reginald L. Hermanns  Niki Koulermou  Colby A. Smith  Mats Engdahl  Pere Buxó  Marta Gonzalez  Claire Dashwood  Helen Reeves  Francesca Cigna  Pavel Liščák  Peter Pauditš  Vidas Mikulėnas  Vedad Demir  Margus Raha  Lídia Quental  Cvjetko Sandić  Balazs Fusi  Odd Are Jensen 《Landslides》2018,15(2):359-379
Landslides are one of the most widespread geohazards in Europe, producing significant social and economic impacts. Rapid population growth in urban areas throughout many countries in Europe and extreme climatic scenarios can considerably increase landslide risk in the near future. Variability exists between European countries in both the statutory treatment of landslide risk and the use of official assessment guidelines. This suggests that a European Landslides Directive that provides a common legal framework for dealing with landslides is necessary. With this long-term goal in mind, this work analyzes the landslide databases from the Geological Surveys of Europe focusing on their interoperability and completeness. The same landslide classification could be used for the 849,543 landslide records from the Geological Surveys, from which 36% are slides, 10% are falls, 20% are flows, 11% are complex slides, and 24% either remain unclassified or correspond to another typology. Most of them are mapped with the same symbol at a scale of 1:25,000 or greater, providing the necessary information to elaborate European-scale susceptibility maps for each landslide type. A landslide density map was produced for the available records from the Geological Surveys (LANDEN map) showing, for the first time, 210,544 km2 landslide-prone areas and 23,681 administrative areas where the Geological Surveys from Europe have recorded landslides. The comparison of this map with the European landslide susceptibility map (ELSUS 1000 v1) is successful for most of the territory (69.7%) showing certain variability between countries. This comparison also permitted the identification of 0.98 Mkm2 (28.9%) of landslide-susceptible areas without records from the Geological Surveys, which have been used to evaluate the landslide database completeness. The estimated completeness of the landslide databases (LDBs) from the Geological Surveys is 17%, varying between 1 and 55%. This variability is due to the different landslide strategies adopted by each country. In some of them, landslide mapping is systematic; others only record damaging landslides, whereas in others, landslide maps are only available for certain regions or local areas. Moreover, in most of the countries, LDBs from the Geological Surveys co-exist with others owned by a variety of public institutions producing LDBs at variable scales and formats. Hence, a greater coordination effort should be made by all the institutions working in landslide mapping to increase data integration and harmonization.  相似文献   
12.
The Cenomanian–Turonian transition marks one of the most important extinction episodes of the Mesozoic era. This extinction event was associated with the development of widespread oceanic anoxia and pronounced stable carbon isotopic excursion. Despite its importance, the effects of the perturbation on higher latitude biotas, and from the Baltic region in particular, are currently underexplored. Therefore, in this contribution we present the fossil record of a foraminifera succession integrated with δ13C trends from two deep cores: Bliūdsukiai-19 from western Lithuania and Balta?i?k?-267 from southern Lithuania. Two foraminiferal zones were distinguished: Rotalipora cushmani from the upper Cenomanian and Whiteinella archaeocretacea from the boundary strata between the Cenomanian and Turonian in the Balta?i?k?-267 core section, and a W. archaeocretacea Zone in the Bliūdsukiai-19 core section. A chemostratigraphical analysis of the stable carbon isotopes revealed a positive Cenomanian–Turonian δ13C anomaly, with maximum values reaching 3.57‰ in the upper part of the Bliūdsukiai-19 core section. A non-metric multidimensional scaling analysis of the foraminifera communities revealed that the major changes in their assemblages were strongly temporally organized and associated with the changes in the stable carbon isotopic ratios. This fact points to the significant effects of the C–T extinction event on the northern Neotethys paleocommunities.  相似文献   
13.
The Curonian Lagoon is the biggest fresh water basin in Lithuania influenced by the exchange of the fresh Nemunas and other smaller rivers’ water and saline water of the Baltic Sea. The lagoon ecosystem is influenced by fresh, brackish and brackish water masses. A long-term water balance of the Curonian Lagoon was calculated for the period of 1960–2009. The sum river inflow is 21.784 km3/year, precipitation—1.199 km3/year, evaporation—1.007 km3/year, inflow of brackish water from the Baltic Sea to the Curonian Lagoon—6.171 km3/year, and fresh water runoff from the Curonian Lagoon to the Baltic Sea—27.642 km3/year. The lagoon water balance elements have been influenced by climate change. The water balance forecasting has been performed for the period of 2011–2100. The climate change impact on the water balance of the Lagoon has been evaluated using Global Climate Models (ECHAM5 and HadCM3), greenhouse gas emission scenarios (A2, A1B and B1), and hydrological modelling by Hydrologiska Byrans Vattenbalansavdelning (HBV) software. One scenario was selected for the prediction of the Baltic Sea water level. Considerable changes of the Curonian Lagoon water balance are forecasted in the 21st century. Increase of weather temperature and changes in precipitation will influence the elements of water balance of the Curonian Lagoon. In the period of 2011–2100, the river inflow and outflow from the Baltic Sea into the Lagoon will decrease respectively by 20.4 and 16.6% in comparison with the baseline period (1961–1990). The amount of precipitation and evaporation will increase respectively by 3.8 and 25.1%, while inflow from the Baltic Sea into the Curonian Lagoon will increase up to 39.7% in comparison with the baseline period.  相似文献   
14.
Previous models for the chemical evolution of the Magellanic Clouds have assumed either a steepened IMF compared to the solar neighbourhood or preferential expulsion of oxygen and α-particle elements by selective galactic winds. These assumptions were largely motivated by a belief that the O/Fe ratio in the Clouds is substantially lower than in the Galaxy, but the difference appears to have been exaggerated: Galactic supergiants have a similar O/Fe ratio as Cloud supergiants, there is no corresponding effect in Mg and other α-elements and a combination of data from planetary nebulae, H II regions and supernova remnants indicates an O/Fe ratio more or less equal to solar. Consequently new analytical models for the chemical evolution of the Magellanic Clouds have been developed, assuming chemical yields and time delays identical to those we previously assumed for the solar neighbourhood, but assuming (in addition to infall) non-selective galactic winds and burst-like modes of star formation represented by discontinuous variations in the star formation rate per unit gas mass. We find adequate agreement with age-metallicity relations and element:element ratios within their substantial uncertainties, whereas our LMC model turns out to give an excellent fit to the anomalous Galactic halo stars discovered by Nissen and Schuster (1997). It also gives an enhanced SNIa/SNII ratio compared to the solar neighbourhood, due to the assumption that the SFR has declined in the past 1 to 2 Gyr. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
15.
A quantitative provenance approach is developed and in this study applied for the silt and clay fractions of sandy, coastal deposits. Mineralogical composition of 37 surface samples was determined by X-ray diffraction (XRD). Grain-size distributions were obtained by standard dry sieving and pipette techniques. The characterization of mineralogical provenance is based upon known compositional information of possible sources, logical models for mineral combinations related to regional geological provinces and processes, and geographical features of the documented mineral distribution in the area of investigation. These interpretations are further supported by results of correlation and principal component analyses of mineral varieties, grain-size parameters and bathymetric features of the area. Partitioning of source contributions specific for each site of deposition is derived by solving simultaneous equations. Then, the quantified mineral composition at the initial source is reconstructed in the SE Baltic Sea along the Lithuanian coast, exemplifying this new methodology for quantification of sediment sources. The main sources supplying sediment to the area are: 1) Sambian Peninsula to the south (erosion of Pleistocene till and “Blue Earth” Paleogene sediments), supplying 33% of fine-grained sediment on average, 2) Nemunas River, the discharge of which passes through Curonian Lagoon and supplies an average 17% of the coastal fine sediments, and 3) Pleistocene till, eroded on the sea floor in the north and at the Olando Kepur? shore cliff and contributing an average of 50% of the sediment. Although we use the mineralogy within the environmentally important fine-grained fraction, this mathematically simple approach could be used with any other parameters characterizing the identified sources. A quantification of the separate source contributions to each individual site of accumulation studied, using the stable, mineralogical components of the “sediment archive”, offers a time-integrated, net-effect reflection of the combined processes of an entire environmental system.  相似文献   
16.
Climate change is inevitably altering the hydrological regime of water bodies. The interest in changing behaviour of intermittent rivers is increasing in many countries. This research was focused on intermittent rivers (rivers which naturally, periodically cease to flow) in Lithuania. The purpose of this research was to provide an overview of flow intermittency phenomena according to available data in a historical period and to evaluate the impact of catchment geographical features and climate variability on zero-flow events. The calculated indices of flow intermittency showed that the selected rivers had very different flow regimes. The threshold for the separation of typically intermittent rivers from only occasionally intermittent ones was suggested. Multiple linear regression analysis defined the crucial role of catchment size and watercourse slope on the river cessation process in Lithuania. The applied non-parametric Wilcoxon–Mann–Whitney test revealed the significance of the relationship between precipitation (in June–September) and zero-flow duration. Flow intermittency phenomena in Lithuanian rivers were linked to a low-frequency teleconnection pattern (SCAND index). A methodology of estimating the relation between river intermittency and large-scale atmospheric circulation pattern (based on SCAND index) was created. The generated regression equations between flow intermittency indices and catchment characteristics might be useful for the estimation of zero-flows in ungauged river catchments. The main aspect of future investigations might be related to forecasting flow intermittency using modern hydrological models and climate scenarios as well as the defined relationships between zero-flow indices and physico-geographical features of river catchments.  相似文献   
17.
Lithuania, in the Baltic region of northern Europe, is heavily dependent on groundwater resources for its public water supply, with a large proportion, especially in rural areas, derived from shallow Quaternary aquifers. A national groundwater-vulnerability methodology, based upon the UK approach, has been developed on behalf of the Lithuanian Ministry of Environmental Protection as a possible basis for the future protection of shallow groundwater resources for the rural inhabitants. Some modifications to the UK methodology were required to enable archive data to be used. The four aquifer classes depicted on the final groundwater vulnerability map are based upon the assessed relative permeabilities of the uppermost Quaternary deposits. The derivation of the classification of soil-leaching potential required a reassessment of Soviet-based soil wetness and particle-size classes and a calculation of subsoil-saturated hydraulic conductivity. A preliminary validation of the final maps against available shallow groundwater samples suggests that the methodology satisfactorily predicts the intrinsic groundwater vulnerability. The final methodology, based upon its low-cost approach using archive data, is relevant to the current needs of Lithuania and can be applied in other regions of similar geology and climate. Electronic Publication  相似文献   
18.
Taking into account a general concept of risk parameters and knowing that natural gas provides very significant portion of energy, firstly, it is important to insure that the infrastructure remains as robust and reliable as possible. For this purpose, authors present available statistical information and probabilistic analysis related to failures of natural gas pipelines. Presented historical failure data is used to model age-dependent reliability of pipelines in terms of Bayesian methods, which have advantages of being capable to manage scarcity and rareness of data and of being easily interpretable for engineers. The performed probabilistic analysis enables to investigate uncertainty and failure rates of pipelines when age-dependence is significant and when it is not relevant. The results of age-dependent modeling and analysis of gas pipeline reliability and uncertainty are applied to estimate frequency of combustions due to natural gas release when pipeline failure occurs. Estimated age-dependent combustion frequency is compared and proposed to be used instead of conservative and age-independent estimate. The rupture of a high-pressure natural gas pipeline can lead to consequences that can pose a significant threat to people and property in the close vicinity to the pipeline fault location. The dominant hazard is combustion and thermal radiation from a sustained fire. The second purpose of the paper is to present the combustion consequence assessment and application of probabilistic uncertainty analysis for modeling of gas pipeline combustion effects. The related work includes performance of the following tasks: to study gas pipeline combustion model, to identify uncertainty of model inputs noting their variation range, and to apply uncertainty and sensitivity analysis for results of this model. The performed uncertainty analysis is the part of safety assessment that focuses on the combustion consequence analysis. Important components of such uncertainty analysis are qualitative and quantitative analysis that identifies the most uncertain parameters of combustion model, assessment of uncertainty, analysis of the impact of uncertain parameters on the modeling results, and communication of the results’ uncertainty. As outcome of uncertainty analysis the tolerance limits and distribution function of thermal radiation intensity are given. The measures of uncertainty and sensitivity analysis were estimated and outcomes presented applying software system for uncertainty and sensitivity analysis. Conclusions on the importance of the parameters and sensitivity of the results are obtained using a linear approximation of the model under analysis. The outcome of sensitivity analysis confirms that distance from the fire center has the greatest influence on the heat flux caused by gas pipeline combustion.  相似文献   
19.
Little is known concerning climate changes in the Eastern Baltic region during the last interglacial–glacial cycle and in particular, climate changes during the Weichselian. In this study, a quantitative reconstruction of the mean January and July temperature for the Medininkai-117 site in Lithuania is presented. The reconstruction is based on pollen and plant macrofossils from this site, which reveal that the vegetation was characteristic of many northern Europe sites during the Eemian and Early Weichselian. Gradual evolution of the vegetation suggests that relatively uniform climate conditions existed during the Eemian. Our reconstructions support the view of a relatively stable Eemian, with short cooling phases of low amplitude. A strong increase in temperature was apparent during the beginning of the interglacial and decrease during the transition to the Weichselian. Reconstructed July temperatures of the Eemian interglacial were approximately 2 °C higher than today (18.5 °C; today: 16.2 °C) and were similar to today for January (− 5.2 °C; today: − 5.1 °C). July temperatures during the Early Weichselian were only ~ 2°C lower than during the Eemian, whereas the January temperatures gradually decreased. Winter temperatures were relatively high (above − 10 °C) during the Early Weichselian.  相似文献   
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