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2
Content available remote Długookresowe tendencje obiegu wody w Kampinoskim Parku Narodowym
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On the basis of trends analysis concerning river flow, phreatic water states and climate elements, the problem of intensifying water deficit in the Lasica River basin is described. Receiving two scenarios of global climate changes: pessimistic GFDL and moderately optimistic GISS an estimation of effect future changes in air temperature and precipitation on percolation and runoff from the catchment is made. The basin of the Lasica River (a tributary of the Bzura) is one of the lowland regions in Poland that is particularly threatened by water deficits in different seasons and years. This is the result of relatively low annual precipitation, as well as of human activity including deforestration, drainage, intensive abstraction of groundwater and intensive development of agriculture and urban agglomerations. Water deficit can be confirmed hydrologically in long term negative trends of runoff in the Lasica and Utrata River and for phreatic groundwater at several observation points (piezometer and wells). In analysis was made an annual trends for elements of the climate precipitation and air temperature, at the stations representing the lowland Lasica basin. In estimating future changes in elements of water circulation (groundwater, evapotranspiration, retention and runoff) was made of the GFDL and GISS scenarios for global climate change. Negative trends were noted for vertical feeding of groundwater in the cases of both the pessimistic GFDL and the moderately pessimistic GISS scenario. The anticipated unfavourable conditions for the supply and renewability of groundwater coincide with significant changes (reduction) already noted in subsurface storage and the flow of the Lasica River.
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Content available Odpływ ze zlewni zurbanizowanych
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The purpose of this study was to revision the urbanization area floods influences according mathematical models to floods simulation. It ranges through the rational formula for calculating Qmax, one-dimensional models of the relationship between intensive precipitation and discharge, the SCS method for assessment effective rainfall, the unit hydrograph UH and the instantaneous unit hydrograph IUH. Two - and three - dimensional models are then presented, along with different ways of envisaging hydrological processes in urban Systems. Support for the application of the models is offered on the basin of many examples involving different cities (Europe, Asia, North America and Poland), possibilities for finding solutions are, indicated, and limitations inherent in the modeling pointed out.
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Content available Urszula Soczyńska
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Urszula Soczyńska, born Czaplińska, graduated in water building engineering at the Warsaw Technical University in 1957. In 1956 she began didactic course on hydraulics and fluid mechanics at the Warsaw Technical University and then in 1960 she moved to the National Institute of Hydrology and Meteorology where she organized the Laboratory of Hydrologic Prognostic Methodology. During 50 years of scientific and didactic work she dedicated herself mostly to the issues of forecasting, especially of floods and icings of rivers. She was promoted a doctor on the basis of her dissertation The method of forecasting of the river freshets in the mountainous regions of Poland basing on specific unit hydrograph waves characteristics under the guidance of professor Julian Lambor. In 1975 she was promoted a docent at the Institute of Meteorology and Water Adrninistration where she ran the Department of Dynamic Hydrology. The collected research findings served as a base for her habilitation dissertation Methodological bases of the regional model of basin in the Polish conditions which was conducted in 1977 at the Faculty of Geography and Regional Studies of the Warsaw University. In 1978- 2001 professor Urszula Soczyńska was bound with the University of Warsaw, first as a docent and later as a professor at the Department of Hydrology within the Faculty of Geography and Regional Studies. An outstanding hydrologist, an expert in mathematic modelling, for 10 years she ran the Department of Hydrology where she introduced the modern methods of prediction of reception basins outflow on the basis of precipitation transformation with the specific recurrence probability. In 1984- 1990 she was the Director of the Institute of Physico-geographical Sciences. In 1990- 1993 she was the Dean of the Faculty of Geography and Regional Studies, implementing creative organizational, didactic, and staff system changes. She was the author of over a hundred hydrologic papers acknowledged in Poland and abroad and an organizer of the international cooperation with the European countries within the framework of UNESCO-IHP FRIEND in the field of hydrologic research upon the experimental basins used to predict river floods and low flows. Her methodological and applied papers had good theoretical bases and were grounded on the extensive empirical material. She was an unquestioned expert in Polish and European hydrology and her works and methodological bases are stili valid.
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The paper presents the physical background of the vertical water transformation modeling in the unit quasi-homogeneous forest area with in the winter season. The model structure includes all main processes operating in precipitation (rain and snow) and snow cover interception on forest canopy and forest ground. Special attention has been paid on the kohesion, accumulation, heat and moisture flux processes, evaporation and sublimation from snow cover, change in the water phase and water percolation through snow on the canopy and ground. Basic processes were considered in terms of quasi-homogeneous unit forest area. Each component of the model was described by the mathematical-physics equations. Parameters of the model are the physical characteristics of the plant canopy, ground and air conditions. The concept of the model should be used to simulation of the net precipitation and snowmelt feeding of the unit forest area.
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Content available Źródła Skarpy Warszawskiej
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It has been presented a hydrogeological, thermal, and hydrochemical characteristics of 9 springs located on a footslope of Warsaw glacial upland. Historical data (from XIX c. by Pusch and from XX c. by Czarnecka, Macioszczyk, Mysiak and Nejfeld, Pich and Płochniewski) have been used for comparison. Discharge of the springs shows decreasing tendency and slow process of disappearing. Water quality is very bad which is an evidence of negative influence of urbanisation.
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There is a tendency in water management to identify the resources of surface waters with the river discharge expressed by the intensity of the flow. However, such evaluation of resources is not advisable bacause of the difficulties in water-economic balancing of the basin, since it does not take into account the water contained in the wetted profile of the river bad. With heavy pollution of the water flowing in the river bed this fact may have a considerable influence on the accuracy of the balance. The above reasons have become a basis for the introduction of a new means for the evaluation of resources of flowing waters, namely a momentum, i.e. the quantity of the water motion in a stream, expressed by the equation. ln ZA= ∫ Q · dl lm or with Q = FV ln ZA= ∫ F · V · dl lm where: 1n - lm - the length of the relevant river section in m, Q - the mean flow intensity at the given section of the stream in m³ s⁻¹, F - the prewetted cross section of the stream bed in m² V - the velocity of water flow in ms⁻¹. The evaluation of the quality ofwater resources has been carried out for 83 rivers in the Vistula basin and in 52 rivers in the Oder basin by means of the stream momentum method. These resources are identified with SNQ (Mean Minimum Discharge). It has been found that in the Vistula and in the Oder basins the smallest quantities of resources were clustered in class I of cleanness (about. 0,5%). The heavily polluted waters and out-of-class waters comprised as much as 93% of all water resources in the Vistula basin, and 81 % in the Oder basin. The situation is better in Pomerania region, where class I waters make 10% of resources, and only 25% are waters in class III and off-limit cleanness waters. The non-deficiency rivers, fully capable of satisfying unlimited needs, are characterized very heavy pollution. Almost half of all the water resources in deficiency rivers, of limited posibilities of satysfying the needs, are outside any classification. The mean momentum duration of the polluted water resources (class III and off-limit cleanness) is 8- 10 days. The best situation prevails in the rivers of Pomerania (1-4 days), the worse is in the Noteć (51 days), the Bóbr (24 days) and the Oder (29 days).
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Geomorphology of the Vistula River Valley in Warsaw has been presented, as well as history of flood protective dikes and channel regulation works. From historical sources we have the description of catastrophic flood of 1635. The level of the flood of 1844 has been preserved in the form of high water mark. Using two dimensional hydrodynamic model CCHE2D the simulation of thousand years recurrence flood has been performed. It has been compared the result of the calculations with historical chronic and high water mark. It has been calculated the pattern of flood water flow over Praga district terrace, showing also the possibility of flood flow directly to Narew river through the relive channels leading by a terrain depressions of today's Zeranski Canal and Bródnowski Canal.
EN
The results of many theoretical works and field investigations on atmospheric ice deposists had shown in different countries, that ice accretion processes are important not only as the hydrometeorological phenoma but also they involve many economic problems. Atmospheric ice deposists on everhead conductors in form of rime formation (dry growth) and as the glaze formation (wet growth) make of the major porblems in power networks planning. For practical purposes the most important are estimates of the icing intensity and maximum ofice loads in different atmospheric conditions and at different parameters of structures. Hydorlogists should take atmospheric ice depsit into consideration as the additional element of river basin feeding.
EN
Will the hydrological flow regime of rivers be transformed as a result of global climate change, assuming physical-geographical properties of catchments to be permanent? An answer to this question was sought by way of comparison of the behaviour patterns of a river (its discharge structure in the normal yearly cycle) in real conditions defined on the basis of an observation series from the years 1961-1990 (scenario 0) and in the conditions of the assumed climate change (scenarios GFDL and GISS). The assessment of changes in the regime was made in the quantitative and qualitative terms. Three rivers were chosen for the analysis: the Rega, the Utrata and the Soła, whose catchments lie in the different physical-geographical regions of Poland, in order to gain an insight into the direction and intensity of changes also at a regional scale. The results obtained colaborate the impact of the global climate change on the rivers, both at the mesoscale of Poland and the regional scale. The total annual discharge may change significantly (table 1), either by going up, according to the GISS scenario, or going down, according to the GFDL scenario. The transformation of the discharge rhythm may manifest itself in a shift in the stages of discharge while maintaining its seasonality, and in a change in its magnitude in the particular seasons (e.g., the lowering of the level of base flows and their lengthening, mainly in mountain and lowland rivers, as well as restricted and greatly reduced meltwater floods).
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The basin of the Służewiecki Stream, hydrologically uncontrolled, is urbanised, but it has a mosaic-like character, consisting of urban and agricultural land use. This is shown by the graph of the basin and its subcatchments that takes into account the changes of the runoff coefficient in its subcatchments. The land cover changes in 1993–2002 and the forecast for the years until 2012, together with the calculated rainfall hyetograph are input elements to the rainfall-runoff model. The isochrone method with the Kirpich equation constitute the transforming function, and the runoff hyetographs are the output elements from the system. The paper presents also practical problems occurring in the implementation of the recommendations of the local spatial plan as well as consequences resulting from disregarding the recommendations.
PL
Niekontrolowana hydrologicznie zlewnia Potoku Służewieckiego o powierzchni zlewni wynoszącej 55 km2 jest w 51% zurbanizowana. Charakteryzuje się nadal mozaikową strukturą użytkowania miejskiego i rolniczego. Obrazuje to wykres trójkątny rozwinięcia zlewni (dopływy prawe i lewe) uwzględniający zmiany współczynnika odpływu w zlewniach cząstkowych. Zmiany użytkowania w latach 1993–2002 i ich prognoza do 2012 roku (z planu zagospodarowania przestrzennego) wraz z obliczonym metodą Bogdanowicz (1998) hietogramem opadu są elementami wejścia do modelu opad-odpływ. Metoda izochron połączona ze wzorem Kirpicha jest funkcją transformującą, a hydrogramy odpływu są elementami wyjścia z systemu. Zmiany użytkowania terenu w latach 1993–2012 obejmą 10% powierzchni zlewni. Spowoduje to ok. 25% wzrost przepływu maksymalnego wywołanego opadem trwającym, zarówno 3 godziny (14–18 m3/s), jak i 8 godzin (16–20 m3/s).
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The global warming is important factor influencing changes in water circulation. Global Circulation Models (GCMs) developed in the last decades have enabled assessment of global warming effect. The goal of this study is to apply the mathematical rainfall - runoff model to evaluate the rate and direction of changes in flood formation resulting from climate changes using historical data and generated by ECHAM4 GCM in 5 selected basins in Poland. The study confirm that main factors controlling flood formation in present are precipitation intensity, topography and land cover. According to modeling results in the perspective of 80 - 90 years only the floods in Carpathian region will exceed those observed in the past years. In the Polish Lowlands maximum precipitation totals of p= 1% will be from 20 to even 50% lower than in the last decades, thus river runoff will decrease.
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Content available remote Prognozowanie ustroju hydrologicznego w różnych skalach geograficznych
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Selection of the proper hydrological model depends on how much we know a priori about catch-ment system internal structure, and what is a purpose of our modeling. Additional very important criterium of the model selection is spatial scale of the examined natural system. The small scale research requires detailed measurements. Gradual increase of the spatial scale results also in a growth of the environment heterogeneity. This demands application of the simpler models with ag-gregated parameters. In the paper have been discussed the results of foreign authors as well as the research projects of Warsaw University, Hydrology Department performed in co-operation with other scientific institutions.
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