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1.
Extreme and prolonged rainfall in the Tunka Ridge caused several debris flows in the vicinity of the Arshan village(Siberia, Russia) on June 28, 2014. These debris flows, in spite of similar geological conditions, had different velocity, peak discharge and alluvial fan volume values. The flow velocity was from 3.5 m/s to 19.6 m/s, the peak discharge ranged from 63 m3/s to 13566 m3/s, and the alluvial fan volume varied from 4.13×103 to 8.45×105 m3. Such a great range of values is due to the morphometric parameters of the debris flow basins. The article deals with the influence of morphometric parameters of debris flow basins, such as the basin area, the average slope, Melton ratio, relief ratio on the debris flow velocity, peak discharge and volume of alluvial fans. In this debris flow event the average values of slope angle and total basin relief of the debris flow basins did not affect the values of debris flow velocity, peak discharge and alluvial fan volume. The highest correlations were observed with the debris flow basin area that was connected with the water inflow volume into the debris flow basins during the rainfall. The unequal water distribution among debris flow basins also had an impact on the debris flow velocity, peak discharge and volume of alluvial fans. 相似文献
2.
This paper presents the development and utilisation of an automated image processing algorithm for detection and analysis
of grains. Using optical polarising microscopy, a set of colored images are collected from an area on a thin section. A filtering
operation, using rotation of a morphological alternating sequence filter (based on a structuring element), is used to remove
twinning features within individual grains. Filtering is followed by the watershed segmentation technique to determine grain
boundaries. The method is used for the identification of calcite grains in marble and the subsequent analysis of morphological
anisotropy. 相似文献
3.
The territory of Transbaikalia (Russia) is subject to occasional large-scale flooding. One of the most significant events in terms of scale and consequences is the historical flood that occurred in August 1897. In this article, we have tried to reconstruct the flood event. For this purpose, we have used all available historical sources (official statistical data, newspaper publications). The flood was observed almost simultaneously in two river basins (the Selenga and Shilka rivers). The main cause of the catastrophic flood was the abnormally intensive rainfall in the Hentey Mountains (Mongolia) and in Chikokonsky Ridge (southern Transbaikalia) in summer 1897. We have singled out four flood stages on the basis of the dates of flooding in different settlements. The flooding was accompanied by silting of considerable areas, and formation of new channels in local places. The flood in August 1897 in Transbaikalia, Russia, clearly demonstrated the vulnerability of both the environment and society to such catastrophic events. 相似文献
4.
Alena FIRSOVA 《《地质学报》英文版》2014,88(Z1):68-69
正The chrysophytes are distributed over all the continents.As a rule,these are planktonic,freshwater,cold-water inhabitants.There are as well saltish-water chrysophytes species of genera Chrysococcus,Dinobryon, 相似文献
5.
Renata J. Romanowicz Alena Kulasová Jana Ředinová Sárka D. Blazková 《Acta Geophysica》2012,60(4):1120-1142
This paper studies the influence of afforestation on the water regime in two catchments in the Jizera Mountains that are similar in size and altitude but have different afforestation pattern. In this paper a range of different modelling tools is used to establish whether the differences in catchment water regime can be quantified and attributed to differences in catchment characteristics. Frequency analysis of low and high flows and a number and duration of flows over a threshold value are used to look for the differences in flow regime in both catchments. Low flow conditions are modelled using the Wittenberg nonlinear store approach. A rainfall-runoff process is modelled using a Data Based Mechanistic approach. The results indicate that the differences in the catchment response to external climatic factors outweigh the influence of land use apart from the low flows, where the changes in the response might be attributed to afforestation. 相似文献
6.
Alena Gessert Janetta Nestorová–Dická Ivo Sninčák 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):173-183
Show caves are one of the most important targets in developing local ecotourism strategies. This work focuses on a tourism visit rate incidence through an Attractiveness Index concerning 12 selected show caves in Slovakia. Our study focuses on visitor counts published from 2000 to 2014. A set of eight criteria were selected in order to analyse and determine the appeal that each cave may have for visitors. Establishing the “degree” of appeal as an indicator of the tourism and geographic absolute attractiveness value is based on a principal components factor analysis; the resultant single factor was correlated with our selected criteria. We find a strong correlation between touristic cave attractiveness and cave locations, ease of cave passage access (vehicle and trail) infrastructures, cave location in main tourism regions, and the growth of urban areas as they encroach on show cave locations. Similar studies in valorization of show caves tourism have not been attempted in Slovakia or Eastern Europe. The data and result from this study are also clearly important from a managerial perspective. This general framework could be easily expanded to include additional attributes that might be relevant for other market segments or other vacation experiences. 相似文献
7.
Comparison of quantitative petrographic, stable isotope and cathodoluminescence data for fingerprinting Czech marbles 总被引:1,自引:1,他引:0
Various marbles from both historic quarries and historical artefacts of the Czech Republic were examined in order to make determinations of their provenance. The methodology used was based upon a combination of petrographic image analysis (PIA) of thin sections, stable isotope geochemistry of carbonates, and cathodoluminescence. Multivariate statistical methods (i.e. cluster analysis and discriminant analysis) confirmed the geoscientific relevance of the marble’s different characteristics with a high degree of consistency as well as the enhanced significance of stable C and O isotopes in correlation with the petrographic data. The qualitative cathodoluminescence data provided a useful additional tool to help recognise the fingerprinting of marbles with similar petrographic and/or geochemical characteristics. 相似文献
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9.
The Denver Region in Colorado, USA, is used as an example of the seismic vulnerability of a region that is not generally considered seismically active. The HAZUS (Hazards United States) natural hazard vulnerability program of United States and an integral geographical information system are used to create the regional distribution of Denver’s potential consequences of an earthquake. Two realistic scenario earthquakes are employed based on a detailed study of seismic activity in the region. Outcomes include casualties, displaced households, building damage by construction material type, hospital functionality, highway bridge functionality, and infrastructure recovery rates. Demographic information includes the use of public transportation, elderly population, and vulnerability based on education, income, and race. Additionally, the type and frequency of communication among key planning agencies and other organizations in the region are investigated through the use of personal interviews as well as a survey to determine the degree to which these agencies consider seismic risk in their communication and coordination planning. 相似文献