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Renáta Dulovičová; Yvetta Velísková; Radoslav Schügerl. Determination and comparison of hydraulic conductivity values of bed silts along Chotárny channel using grain size analysis. Acta Hydrologica Slovaca 2020, 21, 139 -144.
AMA StyleRenáta Dulovičová, Yvetta Velísková, Radoslav Schügerl. Determination and comparison of hydraulic conductivity values of bed silts along Chotárny channel using grain size analysis. Acta Hydrologica Slovaca. 2020; 21 (2):139-144.
Chicago/Turabian StyleRenáta Dulovičová; Yvetta Velísková; Radoslav Schügerl. 2020. "Determination and comparison of hydraulic conductivity values of bed silts along Chotárny channel using grain size analysis." Acta Hydrologica Slovaca 21, no. 2: 139-144.
Marek Sokáč; Yvetta Velísková. Impact of roughness changes on contaminant transport in sewers. Acta Hydrologica Slovaca 2020, 21, 145 -151.
AMA StyleMarek Sokáč, Yvetta Velísková. Impact of roughness changes on contaminant transport in sewers. Acta Hydrologica Slovaca. 2020; 21 (2):145-151.
Chicago/Turabian StyleMarek Sokáč; Yvetta Velísková. 2020. "Impact of roughness changes on contaminant transport in sewers." Acta Hydrologica Slovaca 21, no. 2: 145-151.
The testing of a model performance is important and is also a challenging part of scientific work. In this paper, the results of the physically-based EROSION-3D (Jürgen Schmidt, Berlin, Germany) model were compared with trapped sediments in a small reservoir. The model was applied to simulate runoff-erosion processes in the Svacenický Creek catchment in the western part of the Slovak Republic. The model is sufficient to identify the areas vulnerable to erosion and deposition within the catchment. The volume of sediments was measured by a bathymetric field survey during three terrain journeys (in 2015, 2016, and 2017). The results of the model point to an underestimation of the actual processes by 30% to 80%. The initial soil moisture played an important role, and the results also revealed that rainfall events are able to erode and contribute to a significant part of sediments.
Zuzana Németová; David Honek; Silvia Kohnová; Kamila Hlavčová; Monika Šulc Michalková; Valentín Sočuvka; Yvetta Velísková. Validation of the EROSION-3D Model through Measured Bathymetric Sediments. Water 2020, 12, 1082 .
AMA StyleZuzana Németová, David Honek, Silvia Kohnová, Kamila Hlavčová, Monika Šulc Michalková, Valentín Sočuvka, Yvetta Velísková. Validation of the EROSION-3D Model through Measured Bathymetric Sediments. Water. 2020; 12 (4):1082.
Chicago/Turabian StyleZuzana Németová; David Honek; Silvia Kohnová; Kamila Hlavčová; Monika Šulc Michalková; Valentín Sočuvka; Yvetta Velísková. 2020. "Validation of the EROSION-3D Model through Measured Bathymetric Sediments." Water 12, no. 4: 1082.
Small reservoirs, as the preferred blue-green engineering infrastructure for use against intensive runoff processes, have risen in number in Central Europe during the past three decades. However, the modelling of sediment siltation is not included in reservoir planning. The unknown temporal sedimentation of a reservoir can lead to the lifespan of the construction being uncertain. The aim of this study is to present a relatively simple process for local managers to model siltation and, consequently, accurately estimate the lifetime of a small reservoir. Three empirical models (USLE, RUSLE and USPED) were applied to two small catchments in Central Europe. This paper takes advantage of real measured and modelled sedimentation during 2012 and 2017, presenting two different terrain measurement approaches. Our study emphasizes the importance of the R-factor value. The temporal development of the R-factor is dependent on climate change, and the R-factor value has been rising steadily during the last decades. The annual mean R-factor has increased 1.04-times due to changes in precipitation patterns between the periods 1961–1980 and 1997–2016. These changes can explain possible growth in the levels of incoming sediment into reservoirs. We identified the correlation (R > 0.7) between observed sedimentation, the R-factor, and precipitation, and we concluded that the supposed rise of precipitation in Central Europe due to climate change will lead to an increase in the levels of stored sediment in reservoirs. Therefore, it is recommended for reservoir managers to use USPED model and to include the estimation of modelling of siltation rate into reservoirs’ maintenance projects.
David Honek; Monika Šulc Michalková; Anna Smetanová; Valentin Sočuvka; Yvetta Velísková; Petr Karásek; Jana Konečná; Zuzana Németová; Michaela Danáčová. Estimating sedimentation rates in small reservoirs - Suitable approaches for local municipalities in central Europe. Journal of Environmental Management 2020, 261, 109958 .
AMA StyleDavid Honek, Monika Šulc Michalková, Anna Smetanová, Valentin Sočuvka, Yvetta Velísková, Petr Karásek, Jana Konečná, Zuzana Németová, Michaela Danáčová. Estimating sedimentation rates in small reservoirs - Suitable approaches for local municipalities in central Europe. Journal of Environmental Management. 2020; 261 ():109958.
Chicago/Turabian StyleDavid Honek; Monika Šulc Michalková; Anna Smetanová; Valentin Sočuvka; Yvetta Velísková; Petr Karásek; Jana Konečná; Zuzana Németová; Michaela Danáčová. 2020. "Estimating sedimentation rates in small reservoirs - Suitable approaches for local municipalities in central Europe." Journal of Environmental Management 261, no. : 109958.
Valentín Sočuvka; Yvetta Velísková. Bathymetric surveys of Tatras glacial lakes: Case study – Batizovske pleso. Acta Hydrologica Slovaca 2020, 20, 1 .
AMA StyleValentín Sočuvka, Yvetta Velísková. Bathymetric surveys of Tatras glacial lakes: Case study – Batizovske pleso. Acta Hydrologica Slovaca. 2020; 20 (2):1.
Chicago/Turabian StyleValentín Sočuvka; Yvetta Velísková. 2020. "Bathymetric surveys of Tatras glacial lakes: Case study – Batizovske pleso." Acta Hydrologica Slovaca 20, no. 2: 1.
This paper describes the dispersion process in sewer pipes, which is from the hydraulic point of view a prismatic stream channel with relatively constant roughness of streambed. In such hydraulic conditions should the effect of "dead zones" not occur, but this effect was observed during the field experiments. The reason for this was the presence of bed sediments and deposits, which form together with other small obstacles irregularities in the sewer pipe such dead zones. Dead zones are areas with small flow velocities, which act as a zone with transient (temporary) storage, where the pollution is accumulated and released gradually later. This process modifies the dispersion process in sewer systems and causes irregularities in the transport process. Field experiments were performed in a straight sewer section and also in the part with directional changes of sewer line, both under dry weather flow conditions, i.e. with relatively low pipe filling, discharges and velocities. Sewer pipes had a low slope, so a lot of deposits and sediments were present. Paper presents the results of field experiments and analyse the impacts of sediments and deposits in sewer system on the transport and dispersion process, which is reflected in the value of dispersion coefficient. In the case of sewer pipelines, the most important is the longitudinal dispersion coefficient DL. Comparing the values of DL in the straight part and in the part with directional changes, DL values in the straight part were higher than from the section with directional changes. The maximal value of the dimensionless longitudinal dispersion coefficient p reached 25.2 in a straight section; in the part with the directional changes p it was up to 39.3. This result indicates that in the straight part of the sewer line, the longitudinal dispersion of the substance is dominant in the total dispersion process, whereas in the sewer part with directional changes, the transversal (lateral) dispersion contributes to the whole mixing process (dispersion process is also influenced by the velocity gradient in the transverse direction). Within the measured channel section, there were three directional changes - angles of 90°, 135° and 105°. The influence of the direction change angle to the longitudinal dispersion coefficient within the performed measurements has not been clearly determined yet.
Yvetta Veliskova; Marek Sokac. Dispersion Process in Sewer Pipes with Sediments and Deposits. IOP Conference Series: Earth and Environmental Science 2019, 362, 012107 .
AMA StyleYvetta Veliskova, Marek Sokac. Dispersion Process in Sewer Pipes with Sediments and Deposits. IOP Conference Series: Earth and Environmental Science. 2019; 362 (1):012107.
Chicago/Turabian StyleYvetta Veliskova; Marek Sokac. 2019. "Dispersion Process in Sewer Pipes with Sediments and Deposits." IOP Conference Series: Earth and Environmental Science 362, no. 1: 012107.
Analytical solutions of the one-dimensional (1D) advection–dispersion equations, describing the substance transport in streams, are often used because of their simplicity and computational speed. Practical computations, however, clearly show the limits and the inaccuracies of this approach. These are especially visible in cases where the streams deform concentration distribution of the transported substance due to hydraulic and morphological conditions, e.g., by transient storage zones (dead zones), vegetation, and irregularities in the stream hydromorphology. In this paper, a new approach to the simulation of 1D substance transport is presented, adapted, and tested on tracer experiments available in the published research, and carried out in three small streams in Slovakia with dead zones. Evaluation of the proposed methods, based on different probability distributions, confirmed that they approximate the measured concentrations significantly better than those based upon the commonly used Gaussian distribution. Finally, an example of the application of the proposed methods to an iterative (inverse) task is presented.
Marek Sokáč; Yvetta Velísková; Carlo Gualtieri. Application of Asymmetrical Statistical Distributions for 1D Simulation of Solute Transport in Streams. Water 2019, 11, 2145 .
AMA StyleMarek Sokáč, Yvetta Velísková, Carlo Gualtieri. Application of Asymmetrical Statistical Distributions for 1D Simulation of Solute Transport in Streams. Water. 2019; 11 (10):2145.
Chicago/Turabian StyleMarek Sokáč; Yvetta Velísková; Carlo Gualtieri. 2019. "Application of Asymmetrical Statistical Distributions for 1D Simulation of Solute Transport in Streams." Water 11, no. 10: 2145.
This paper deals with studying of two topics – measuring of velocity profile deformation behind a over-flooded construction and modelling of this velocity profile deformation by computational fluid dynamics (CFD). Numerical simulations with an unsteady RANS models - Standard k-ε, Realizable k-ε, Standard k-ω and Reynolds stress models (ANSYS Fluent v.18) and experimental measurements in a laboratory flume (using ADV) were performed. Results of both approaches showed and affirmed presence of velocity profile deformation behind the obstacle, but some discrepancies between the measured and simulated values were also observed. With increasing distance from the obstacle, the differences between the simulation and the measured data increase and the results of the numerical models are no longer usable.
Yvetta Velísková; Zdeněk Chára; Radoslav Schügerl; Renáta Dulovičová. CFD simulation of flow behind overflooded obstacle. Journal of Hydrology and Hydromechanics 2018, 66, 448 -456.
AMA StyleYvetta Velísková, Zdeněk Chára, Radoslav Schügerl, Renáta Dulovičová. CFD simulation of flow behind overflooded obstacle. Journal of Hydrology and Hydromechanics. 2018; 66 (4):448-456.
Chicago/Turabian StyleYvetta Velísková; Zdeněk Chára; Radoslav Schügerl; Renáta Dulovičová. 2018. "CFD simulation of flow behind overflooded obstacle." Journal of Hydrology and Hydromechanics 66, no. 4: 448-456.
Yvetta Velísková. 65th Anniversary of the Institute of Hydrology, Slovak Academy of Sciences. Journal of Hydrology and Hydromechanics 2018, 66, 357 -359.
AMA StyleYvetta Velísková. 65th Anniversary of the Institute of Hydrology, Slovak Academy of Sciences. Journal of Hydrology and Hydromechanics. 2018; 66 (4):357-359.
Chicago/Turabian StyleYvetta Velísková. 2018. "65th Anniversary of the Institute of Hydrology, Slovak Academy of Sciences." Journal of Hydrology and Hydromechanics 66, no. 4: 357-359.
Analytical solutions describing the 1D substance transport in streams have many limitations and factors, which determine their accuracy. One of the very important factors is the presence of the transient storage (dead zones), that deform the concentration distribution of the transported substance. For better adaptation to such real conditions, a simple 1D approximation method is presented in this paper. The proposed approximate method is based on the asymmetric probability distribution (Gumbel’s distribution) and was verified on three streams in southern Slovakia. Tracer experiments on these streams confirmed the presence of dead zones to various extents, depending mainly on the vegetation extent in each stream. Statistical evaluation confirms that the proposed method approximates the measured concentrations significantly better than methods based upon the Gaussian distribution. The results achieved by this novel method are also comparable with the solution of the 1D advection-diffusion equation (ADE), whereas the proposed method is faster and easier to apply and thus suitable for iterative (inverse) tasks.
Marek Sokáč; Yvetta Velísková; Carlo Gualtieri. An approximate method for 1-D simulation of pollution transport in streams with dead zones. Journal of Hydrology and Hydromechanics 2018, 66, 437 -447.
AMA StyleMarek Sokáč, Yvetta Velísková, Carlo Gualtieri. An approximate method for 1-D simulation of pollution transport in streams with dead zones. Journal of Hydrology and Hydromechanics. 2018; 66 (4):437-447.
Chicago/Turabian StyleMarek Sokáč; Yvetta Velísková; Carlo Gualtieri. 2018. "An approximate method for 1-D simulation of pollution transport in streams with dead zones." Journal of Hydrology and Hydromechanics 66, no. 4: 437-447.
Water is a necessary component of the human environment, as well as all vegetal and animal ecosystems. Unfortunately, water quality not just in Slovakia but also in other countries of the world, worsened in the course of the twentieth century, and this trend has not been stopped even at present. Current legislation evaluating the quality of water bodies in Slovakia is based on the implementation of the Water Framework Directive (2000/60/ES). The Directive requires eco-morphological monitoring of water bodies, which is based on an evaluation of the rate of anthropogenic impact. This does not refer only to river beds but also the state of the environs of each stream. While in the past point sources of pollution were considered as the most significant source of pollution in surface streams, after the installation of treatment plants for urban and industrial wastewater, non-point sources of pollution emerged as the critical sources of pollution in river basins. This contribution deals with the distribution and quantity assessment of pollutant sources in Slovakia during the period 2006–2015. The primary point sources evaluated are the ones representing higher values than the 90 percentile of the empirical distribution of total mass and also the mass of applied manures and fertilisers as non-point pollutant sources. The development of computer technologies enables us to solve ecological problems in water management practice very efficiently. Mathematical and numerical modelling allows us to evaluate various situations of spreading of contaminants in rivers without immediate destructive impact on the environment. However, the reliability of models is closely connected with the availability and validity of input data. Hydrodynamic models simulating pollutant transport in open channels require large amounts of input data and computational time, but on the other hand, these kinds of models simulate dispersion in surface water in more detail. As input data, they require digitisation of the hydro-morphology of a stream, velocity profiles along the simulated part of the stream, calculation of the dispersion coefficients and also the locations of pollutant sources and their quantity. The highest extent of uncertainty is linked with the determination of dispersion coefficient values. These coefficients can be accurately obtained by way of field measurements, directly reflecting conditions in the existing part of an open channel. It is not always possible to obtain these coefficients in the field, however, because of financial or time constraints. The other aim of this contribution is to describe the methodology of this coefficient calculation and to present the value range obtained. The results and obtained knowledge about values of longitudinal dispersion coefficients and dispersion processes can be applied in numerical simulations of pollutant spreading in a natural stream.
Y. Velísková; M. Sokac; C. Siman. Assessment of Water Pollutant Sources and Hydrodynamics of Pollution Spreading in Rivers. The Handbook of Environmental Chemistry 2018, 185 -212.
AMA StyleY. Velísková, M. Sokac, C. Siman. Assessment of Water Pollutant Sources and Hydrodynamics of Pollution Spreading in Rivers. The Handbook of Environmental Chemistry. 2018; ():185-212.
Chicago/Turabian StyleY. Velísková; M. Sokac; C. Siman. 2018. "Assessment of Water Pollutant Sources and Hydrodynamics of Pollution Spreading in Rivers." The Handbook of Environmental Chemistry , no. : 185-212.
Surface water-groundwater interaction is a dynamic process which can be influenced by many factors most associated with the hydrological cycle. Besides the fluctuation of surface water and groundwater levels and their gradient, this interaction is also influenced by the parameters of the aquifer (regional and local geology and its physical properties). The next significant factors are precipitation, the water level regime of rivers or reservoirs in the area of interest, and last but not the least the properties of the riverbed itself. The investigation of the interaction between the surface water and groundwater was applied utilizing modern numerical simulations on the Gabčíkovo-Topoľníky channel, one of the main channels of irrigation and drainage channel network at Žitný Ostrov. Žitný Ostrov area is situated in the southwestern part of Slovakia, and it is known as the biggest source of groundwater in this country. For this reason, experts give it heightened attention from different points of view. The channel network was built up in this region for drainage and safeguarding of irrigation water. The water level in the whole channel network system affects the groundwater level and vice versa. With regard to the mutual interaction between channel network and groundwater, it has been necessary to judge the impact of channel network silting up by alluvials and the rate of their permeability to this interaction. The aim of this contribution was to collect the available data from the area of interest for simulation of real and theoretical scenarios of interaction between groundwater and surface water along the Gabčíkovo-Topoľníky channel. The obtained results give valuable information about how the clogging of the riverbed in the channel network influences the groundwater level regime in the area.
P. Dušek; Y. Velísková. Interaction Between Groundwater and Surface Water of Channel Network at Žitný Ostrov Area. The Handbook of Environmental Chemistry 2017, 135 -166.
AMA StyleP. Dušek, Y. Velísková. Interaction Between Groundwater and Surface Water of Channel Network at Žitný Ostrov Area. The Handbook of Environmental Chemistry. 2017; ():135-166.
Chicago/Turabian StyleP. Dušek; Y. Velísková. 2017. "Interaction Between Groundwater and Surface Water of Channel Network at Žitný Ostrov Area." The Handbook of Environmental Chemistry , no. : 135-166.
The aim of this article is the comparison of input options of river boundary condition of MODFLOW - three-dimensional numerical simulation model of groundwater flow. The water level in stream flowing through territory of hydrogeological layer can be computed via three built-in modules: River, Stream and Streamflow-Routing. In this study the code MODFLOW is used to simulate idealized aquifer and stream. The differences between computed groundwater table showed to be minimal, thus in case of modules Stream and Streamflow- Routing they are equally usable as using module River with external one or two-dimensional simulation of surface water flow, which is more time-consuming process. However, this applies only to idealized, simplified conditions of the modeled environment. For more complex simulation of flow in streams with irregular structure of the streambed is necessary to use either an external simulation or use the Streamflow-Routing module, which includes the possibility to enter more complex hydraulic flow parameters in the model.
Petr Dušek; Yvetta Velísková. Comparison of the MODFLOW modules for the simulation of the river type boundary condition. Pollack Periodica 2017, 12, 3 -13.
AMA StylePetr Dušek, Yvetta Velísková. Comparison of the MODFLOW modules for the simulation of the river type boundary condition. Pollack Periodica. 2017; 12 (3):3-13.
Chicago/Turabian StylePetr Dušek; Yvetta Velísková. 2017. "Comparison of the MODFLOW modules for the simulation of the river type boundary condition." Pollack Periodica 12, no. 3: 3-13.
Vegetation growing in the water along watercourses has been the subject of several studies since it was recognized that it could have a significant impact on the water flow. It may increase resistance to flow and cause higher water levels. Also, it has an effect on the velocity profiles. Previous investigations on the flow of water through emergent vegetation have shown different results. The purpose of this paper is to investigate, and determine how aquatic vegetation influences flow resistance, water depth and discharge in the Chotárny channel at the Žitný Ostrov area. This area is part of the Danube Lowland (south-west of Slovakia). The channel network at the Žitný Ostrov region was built up for drainage and also to provide irrigation water. The Chotárny channel is one of three main channels of this network. Measurements performed during six years at this channel were used for an evaluation of vegetation impact on flow conditions. The roughness coefficient was used as one way of quantifying this impact. The results show variation of this parameter during the growing season. Vegetation causes resistance to flow; it reduces flow velocities, discharge and increases water depth.
Yvetta Velísková; Renáta Dulovičová; Radoslav Schügerl. Impact of vegetation on flow in a lowland stream during the growing season. Biologia 2017, 72, 840 -846.
AMA StyleYvetta Velísková, Renáta Dulovičová, Radoslav Schügerl. Impact of vegetation on flow in a lowland stream during the growing season. Biologia. 2017; 72 (8):840-846.
Chicago/Turabian StyleYvetta Velísková; Renáta Dulovičová; Radoslav Schügerl. 2017. "Impact of vegetation on flow in a lowland stream during the growing season." Biologia 72, no. 8: 840-846.
Petr Dušek; Yvetta Velísková; Renáta Dulovičová. Water regime simulation along Gabčíkovo – Topoľníky chanel (Vrakúň junction) case study. Columella : Journal of Agricultural and Environmental Sciences 2015, 2, 73 -78.
AMA StylePetr Dušek, Yvetta Velísková, Renáta Dulovičová. Water regime simulation along Gabčíkovo – Topoľníky chanel (Vrakúň junction) case study. Columella : Journal of Agricultural and Environmental Sciences. 2015; 2 (1):73-78.
Chicago/Turabian StylePetr Dušek; Yvetta Velísková; Renáta Dulovičová. 2015. "Water regime simulation along Gabčíkovo – Topoľníky chanel (Vrakúň junction) case study." Columella : Journal of Agricultural and Environmental Sciences 2, no. 1: 73-78.
The Water Framework Directive (WFD) is a key initiative aimed at improving water quality throughout the EU. The development of the computer technologies enables us to solve the ecological problems in water management practice very efficiently. The mathematical and numerical modelling allows evaluating various situations of contaminants spread in rivers (from everyday wastewater disposal through the fatal discharges of toxic substances) without immediate destructive impact on the environment. The paper deals with 1-dimensional numerical model HEC-RAS and its response on various values of dispersion coefficient. This parameter is one of the most important input data for simulation of pollution spread in streams. There were performed tracer experiments in the Malá Nitra River and results of these measurements are compared with results of numerical simulations. The values of the longitudinal dispersion coefficient were estimated from this comparison. The range of mean values of this coefficient determined on the base of numerical model application was 0.05 – 0.13 m2 s−1, for the other flow condition it was 0.07 – 2.5 m2 s−1 or 0.28 – 0.6 m2 s−1. The next task was carrying out the model sensitivity analysis, which means to evaluate input data influences, especially longitudinal dispersion coefficient, on outputs computed by 1-dimensional simulation model HEC-RAS. According to the results it can be said that the model HEC-RAS responds to longitudinal dispersion coefficient value changes adequately, suitably and proportionately. The application of the model HEC-RAS demonstrated the eligibility for simulation of pollution spread in streams, which means that it is a suitable tool allowing a reasonable support in decision making process connected to river water quality management.
Yvetta Velísková; Peter Halaj; Marek Sokáč; Viliam Bárek. Pollution Spread Analysis In The Malá Nitra River By Using Of 1-D Model. Acta Horticulturae et Regiotectuare 2014, 17, 38 -42.
AMA StyleYvetta Velísková, Peter Halaj, Marek Sokáč, Viliam Bárek. Pollution Spread Analysis In The Malá Nitra River By Using Of 1-D Model. Acta Horticulturae et Regiotectuare. 2014; 17 (2):38-42.
Chicago/Turabian StyleYvetta Velísková; Peter Halaj; Marek Sokáč; Viliam Bárek. 2014. "Pollution Spread Analysis In The Malá Nitra River By Using Of 1-D Model." Acta Horticulturae et Regiotectuare 17, no. 2: 38-42.
The spatial and temporal patterns of surface water (SW) - groundwater (GW) exchange are significantly affected by riverbed silting, clogging or erosion processes, by altering the thickness and hydraulic conductivity of riverbed sediments. The duration of SW-GW exchange is controlled by the drainage and infiltration resistance of river bottom sediments (e.g. Andrássy et al., 2012). Generally, these two parameters primarily depend on the hydraulic conductivity and on the thickness of clogged layer. In this study the flow processes between GW and SW were modeled by model TRIWACO for different infiltration resistance and drainage resistance of riverbed sediments. The model area is situated on the Rye Island, which is a lowland area with very low slope. In this area a channel network was built up, where the flow conditions are controlled by water-gates. Because of the low slope and the system of water gates built on the channels, the riverbeds are influenced by intensive clogging processes. First, the applicability of model TRIWACO in the study area was tested by modelling the response of GW on SW level fluctuation. It was simulated, how the regulation of water level and flow direction in the channels influence the GW level, especially in extreme hydrological conditions (drought/flood), and if the GW flow direction and GW level change as it was expected. Next, the influence of channel network silting up on GW-SW interaction was modeled. The thickness of riverbed sediments was measured and their hydraulic conductivity from disturbed sediment samples was evaluated. The assessed hydraulic conductivity was used to calculate the infiltration resistance and the drainage resistance of riverbed sediments in the study area. Then, the GW level and flow direction was simulated for different infiltration resistance and drainage resistance of sediments.
Márta Koczka Bara; Yvetta Velísková; Renata Dulovicova; Radoslav Schügerl. Influence of surface water level fluctuation and riverbed sediment deposits on groundwater regime. Journal of Hydrology and Hydromechanics 2014, 62, 177 -185.
AMA StyleMárta Koczka Bara, Yvetta Velísková, Renata Dulovicova, Radoslav Schügerl. Influence of surface water level fluctuation and riverbed sediment deposits on groundwater regime. Journal of Hydrology and Hydromechanics. 2014; 62 (3):177-185.
Chicago/Turabian StyleMárta Koczka Bara; Yvetta Velísková; Renata Dulovicova; Radoslav Schügerl. 2014. "Influence of surface water level fluctuation and riverbed sediment deposits on groundwater regime." Journal of Hydrology and Hydromechanics 62, no. 3: 177-185.
The Water Framework Directive requires as an obligatory goal to achieve and to keep “good water quality” status within the defined period (for Slovakia—up to the year 2015). For surface waters, the main criterion is the ecological and chemical status of the water. Mathematical and numerical modelling allows evaluating various situations of contaminants spreading in rivers (from everyday wastewater disposal through fatal accidents and discharges of the toxic substances) without immediate destructive impact to the environment. Determination of longitudinal and transverse dispersion coefficient values, as the main hydrodynamic characteristics of the dispersion, has the highest extent of uncertainty for hydrodynamic models simulating pollutant transport in streams. This paper deals with the determination of dispersion coefficients based on field tracer experiments performed in a small modified stream (basic hydrodynamic parameters during the experiments were: discharge Q = 0.138–0.553 m3.s−1, depth h = 0.29–0.48 m, width B = 5.2–5.9 m). During the experiments, various conditions and situations were taken into account, e.g., continuous and instantaneous pollution source, as well as various positions of pollution source along the river width, among others. Field measurements were evaluated using three different methods for dispersion coefficient determination: based on statistical evaluation, based on analytical solutions of advection–dispersion equation, and using numerical models. The dimensionless dispersion coefficients values were determined, which can be used for numerical simulation of pollutant transport in similar types of streams.
Yvetta Velísková; Marek Sokáč; Peter Halaj; Márta Koczka Bara; Renata Dulovicova; Radoslav Schügerl. Pollutant Spreading in a Small Stream: A Case Study in Mala Nitra Canal in Slovakia. Environmental Processes 2014, 1, 265 -276.
AMA StyleYvetta Velísková, Marek Sokáč, Peter Halaj, Márta Koczka Bara, Renata Dulovicova, Radoslav Schügerl. Pollutant Spreading in a Small Stream: A Case Study in Mala Nitra Canal in Slovakia. Environmental Processes. 2014; 1 (3):265-276.
Chicago/Turabian StyleYvetta Velísková; Marek Sokáč; Peter Halaj; Márta Koczka Bara; Renata Dulovicova; Radoslav Schügerl. 2014. "Pollutant Spreading in a Small Stream: A Case Study in Mala Nitra Canal in Slovakia." Environmental Processes 1, no. 3: 265-276.
Yvetta Velísková. LONGITUDINAL DISPERSION COEFFICIENT EVALUATION METHODOLOGY BASED ON RESULTS OF FIELD MEASUREMENTS. 13th SGEM GeoConference on WATER RESOURCES. FOREST, MARINE AND OCEAN ECOSYSTEMS 2013, 1 .
AMA StyleYvetta Velísková. LONGITUDINAL DISPERSION COEFFICIENT EVALUATION METHODOLOGY BASED ON RESULTS OF FIELD MEASUREMENTS. 13th SGEM GeoConference on WATER RESOURCES. FOREST, MARINE AND OCEAN ECOSYSTEMS. 2013; ():1.
Chicago/Turabian StyleYvetta Velísková. 2013. "LONGITUDINAL DISPERSION COEFFICIENT EVALUATION METHODOLOGY BASED ON RESULTS OF FIELD MEASUREMENTS." 13th SGEM GeoConference on WATER RESOURCES. FOREST, MARINE AND OCEAN ECOSYSTEMS , no. : 1.
Viera Kováčová; Yvetta Velísková. The Risk of the Soil Salinization of the Eastern Part of Žitný Ostrov. Journal of Hydrology and Hydromechanics 2012, 60, 57 -63.
AMA StyleViera Kováčová, Yvetta Velísková. The Risk of the Soil Salinization of the Eastern Part of Žitný Ostrov. Journal of Hydrology and Hydromechanics. 2012; 60 (1):57-63.
Chicago/Turabian StyleViera Kováčová; Yvetta Velísková. 2012. "The Risk of the Soil Salinization of the Eastern Part of Žitný Ostrov." Journal of Hydrology and Hydromechanics 60, no. 1: 57-63.