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Use of land located within Eselnita drainage basin
DANIELA VLAD
Cinq Continents , 2011,
Abstract: Developed on the south-eastern side of Alm jului Mountains, E elni a drainage basin neighbours upon the following basins: upon S – SV with Mala, upon SV - V with Mraconia, upon V - NV with Berzasca, upon NV - NNE with Nera and on the NNE – SE direction with Cerna. The basin has a surface of 77 km2 and present a 5th degree hydrographic network according to Horton-Strahler ranking system, tributary to Danube by means of E elni a main collector. Among surfaces belonging to various categories of use of land located within Eselnita drainage basin, there may be noticed the high share of forest and secondary grazing lands, although the latter have a smaller surface in comparison to the first ones. Therefore, the types of use of land located within the drainage basin are distinguished by the high share of surfaces of forests to the detriment of predominant agricultural land proven by using of some quantitative indexes defining the character of the Eselnita drainage basin as belonging to forestry type. Also the impact of human activities and number of inhabitants do not have a very damaging influence on the land corresponding to the basin, therefore it has a naturality index indicating an ecological equilibrium closed to the natural one.
Bacteriological studies in sediment from Cerna-Belareca-Danube hydrographic system (SW Romania) with a role in assessing pollution
Marioara Nicoleta FILIMON,Aurica Breica BOROZAN,Vasile Daniel GHERMAN
Analele Universitatii din Oradea, Fascicula Biologie , 2010,
Abstract: This paper contains data about the microorganism population in sediment from Cerna-Belareca-Danube hydrographic system. Data allows us to identify possible pollution sources and determine their effect on certain eco physiological group of microorganisms. Bacteriological studies had in view to establish three eco physiological groups of microorganism: nitrifying bacteria, iron-reducing bacteria and anaerobic sulfate-reducing bacteria. Determination has been made using serial dilutions and specific culture environment for each eco physiological group. Based on absolute values of those 3 microorganism groups, the bacterial indicator of sediment quality has been established (BISQ). Sediment analyses have values between 1.274 (Or ova upstream) and 1.296 (Mehadia downstream) in spring. These are the values for winter: 1.286 (Tople downstream) and 1.310 (Or ova upstream). Additional contribution of organic sulfur compounds and microorganisms involved in the sulfur cycle have relatively close values for both seasons in Herculane sample point. Sampling points Mehadia downstream and Tople downstream represent the endpoint of BISQ. Lowest values had been recorded here in autumn and the highest values had been recorded in spring. BISQ lower values from Or ova harbor and Or ova shipyard is due to oil pollution, varnishes, paints, detergents and metals. BISQ has seasonal variations, depending on the sampling point of the studied aquatic ecosystem.
The geomorphological unit hydrograph – a critical review
A. Y. Shamseldin
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 1998,
Abstract: The theory of the geomorphological unit hydrograph (GUH) is examined critically and it is shown that the inherent assumption that the operation of the drainage network may be modelled by a corresponding network of linear reservoirs so restricts the instantaneous unit hydrograph (IUH) shape that the effects of further restrictions, reflecting the constraints imposed by the geomorphological laws of the channel network, cannot easily be identified. Without such identification, the geomorphological unit hydrograph theory is untestable and must remain only a plausible hypothesis providing an indication of a two-parameter IUH whose shape and scale factors must still be related empirically to appropriate catchment characteristics.
THE INFLUENCE OF FLUVIAL DYNAMICS ON GEOARCHAEOSITES FROM THE DANUBE BANK (THE M CIN BRANCH). CASE STUDY: TROESMIS FORTRESS (ROMANIA)  [PDF]
Ionela Georgiana GAVRIL?,T. ANGHEL,?t. BUIMAG? – IARINCA
Aerul ?i Apa : Componente ale Mediului , 2012,
Abstract: The influence of fluvial dynamics on geoarchaeosites from the Danube Bank (the M cin Branch). Case study: Troesmis Fortress (Romania). Built since the first century AD, the fortresses along the right bank of the Danube river have suffered decay along the ages as a result of anthropic and geomorphological factors (weathering of construction rocks, fluvial and eolian erosion). Therefore, in order to study the evolution of the sites, analysis of the geological, geomorphological, hydrological and climatic conditions were made. Our study aims to analyze the Troesmis Geto-Dacian site (III - IV century AD) situated on the right bank of the M cin Branch. Nowadays, the fortress stage of degradation is quite advanced, the main natural decay favouring factor being lateral erosion from the Danube. Fluvial erosion and associated geomorphological processes have determined the retreat of the right bank of the Danube, which led to the structural destruction of the archaeological sites. In order to determine the fluvial dynamics of the M cin Branch sector, bibliographic materials (maps from different time periods etc) were analyzed and field observations were made. The result consisted mainly in the creation of maps that presents the dynamic of the M cin Branch (Danube) and its influence on the Troesmis geoarchaeosite.
ZABALA HYDROGRAPHIC BASIN - THE MORPHOMETRIC ANALYSIS OF THE HYDROGRAPHIC NETWORK  [PDF]
LUCICA NICULAE
Aerul ?i Apa : Componente ale Mediului , 2012,
Abstract: Zabala Hydrographic Basin - The morphometric analysis of the hydrographic network. The South-East Carpathians are one of the most geodynamic regions of the Romanian territory. The rivers draining the South-East Carpathians have been studied under the aspect of the latest alterations of the main valley outline. An important database has been collected using the Horton- Strahler classification system, which has later been processed carefully concerning the rivers draining the South-East Carpathians, and a great deal of information has been extracted. What is more, the evolution of the hydrographic network has been related to the geological and tectonical states. Excellent results have been obtained by correlating the morphometric features of the hydrographic network with the geological and tectonical conditions of the studied area.
Hidrografske meritve : Hydrographic Surveys  [PDF]
Regina Kolenc
Geodetski Vestnik , 2005,
Abstract: Hydrographic surveys are required for a wide range of civil works engineering and construction activities. They support construction of hydrotechnical objects (dams, hydro-powerplants etc.), safe navigation, flood control missions and topographic survey of wetlands. All this caused development of various surveying methods through years but despite continuous improvements of technology and software, the hydrographic field of work is still one of great pretension.
VASCULAR FLORA OF THE DANUBE DELTA  [PDF]
V. CIOC?RLAN
Scientific Annals of Alexandru Ioan Cuza University of Iasi. New Series, Section 2. Vegetal Biology , 2011,
Abstract: The aim of this paper is to present an updated list of the vascular flora of the Danube Delta, together with endangered categories, in accordance with the International Union for Conservation of Nature (IUCN). Also, the flora’s categories are presented according to ecological and habitat criteria.
Negro and Danube are mirror rivers  [PDF]
R. Gon?alves,A. A. Pinto
Physics , 2008,
Abstract: We study the European river Danube and the South American river Negro daily water levels. We present a fit for the Negro daily water level period and standard deviation. Unexpectedly, we discover that the river Negro and Danube are mirror rivers in the sense that the daily water levels fluctuations histograms are close to the BHP and reversed BHP, respectively.
Delineating riparian zones for entire river networks using geomorphological criteria
D. Fernández,J. Barquín,M. álvarez-Cabria,F. J. Pe?as
Hydrology and Earth System Sciences Discussions , 2012, DOI: 10.5194/hessd-9-4045-2012
Abstract: Riparian zone delineation is a central issue for riparian and river ecosystem management, however, criteria used to delineate them are still under debate. The area inundated by a 50-yr flood has been indicated as an optimal hydrological descriptor for riparian areas. This detailed hydrological information is, however, not usually available for entire river corridors, and is only available for populated areas at risk of flooding. One of the requirements for catchment planning is to establish the most appropriate location of zones to conserve or restore riparian buffer strips for whole river networks. This issue could be solved by using geomorphological criteria extracted from Digital Elevation Models. In this work we have explored the adjustment of surfaces developed under two different geomorphological criteria with respect to the flooded area covered by the 50-yr flood, in an attempt to rapidly delineate hydrologically-meaningful riparian zones for entire river networks. The first geomorphological criterion is based on the surface that intersects valley walls at a given number of bankfull depths above the channel (BFDAC), while the second is based on the surface defined by a~threshold value indicating the relative cost of moving from the stream up to the valley, accounting for slope and elevation change (path distance). As the relationship between local geomorphology and 50-yr flood has been suggested to be river-type dependant, we have performed our analyses distinguishing between three river types corresponding with three valley morphologies: open, shallow vee and deep vee valleys (in increasing degree of valley constrainment). Adjustment between the surfaces derived from geomorphological and hydrological criteria has been evaluated using two different methods: one based on exceeding areas (minimum exceeding score) and the other on the similarity among total area values. Both methods have pointed out the same surfaces when looking for those that best match with the 50-yr flood. Results have shown that the BFDAC approach obtains an adjustment slightly better than that of path distance. However, BFDAC requires bankfull depth regional regressions along the considered river network. Results have also confirmed that unconstrained valleys require lower threshold values than constrained valleys when deriving surfaces using geomorphological criteria. Moreover, this study provides: (i) guidance on the selection of the proper geomorphological criterion and associated threshold values, and (ii) an easy calibration framework to evaluate the adjustment with respe
PHYSICO-CHEMICAL AND BIOLOGICAL ANALYSES FOR DANUBE WATER  [PDF]
Aristica Balaban,Elena Constantinescu
Analele Universitatii Bucuresti : Chimie , 2007,
Abstract: This paper compares the results of the biological and physico-chemical analyses of the Danube’s waters upstream and downstream of Braila. The Biological Monitoring Working Party Score (BMWP) was calculated using the existence of the macro invertebrates in the Danube’s water. The pollution of the Danube by the town Braila is minors, the quality of the waters being medium.
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