Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 203 - 209, doi:
Scientific Paper, Slovak

Jaroslav Noskovič, Ľubomíra Kvetanová, Jana Porhajašová, Mária Babošová: Evaluation concentrations of total phosphorus and phosphate phosphorus in the water course Čaradický potok

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• Evaluation concentrations of total phosphorus and phosphate phosphorus in the water course Čaradický potok. In water Phosphorus occurs only in the form of chemical compounds. These are not toxic, but increased concentrations cause (result in) eutrophication of surface waters, representing one of the main causes of their degradation at the present time. The aim of this paper is to evaluate the concentrations of total Phosphorus and Phosphorus in Phosphate in water in the longitudinal profile of the water course Čaradice brook for the period 2005 to 2009. Water sampling was realized in regular monthly intervals, always in the last decade of appropriate month from the six sampling sites. The water course is a right tributary of the river Hron and springs in the mountains of Pohronský Inovec in the southern foot of the hill Drienka. It empties into the river Hron near the village of Kozárovce.
  
  KEY WORDS: water course, total phosphorus, phosphate phosphorus
  
  Address:
  - Jaroslav Noskovič, Katedra environmentalistiky a zoológie FAPZ SPU Tr. A. Hlinku 2 949 76 Nitra, Slovenská republika (Corresponding author. Tel.:+4213764154422 Fax.: +412377411451 Email: jaroslav.noskovic@uniag.sk)
  - Ľubomíra Kvetanová, Katedra environmentalistiky a zoológie FAPZ SPU Tr. A. Hlinku 2 949 76 Nitra, Slovenská republika
  - Jana Porhajašová, Katedra environmentalistiky a zoológie FAPZ SPU Tr. A. Hlinku 2 949 76 Nitra, Slovenská republika
  - Mária Babošová, Katedra environmentalistiky a zoológie FAPZ SPU Tr. A. Hlinku 2 949 76 Nitra, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 210 - 218, doi:
Scientific Paper, Slovak

Yvetta Velísková, Marek Sokáč: Sensitivity of water quality numerical model for used dispersion coefficient values

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• Sensitivity of water quality numerical model for used dispersion coefficient values. This paper deals with sensitivity analysis of the outputs from a numerical model MIKE 11 (one dimensional model) related to values of the longitudinal dispersion coefficients, used as model input data. These coefficients are one of the most important characteristics, which impact the pollution dispersion modelling in the river. Determination of their correct values was a subject of previous research studies, now the results and experience from these studies are used in this paper. A large set of numerical simulations was performed with various values of the longitudinal dispersion coefficient (D= 5 – 50 m2.s-1). Simulations were performed at the Hron river in the part from Slovenská Ľupča to the river estuary. To separate the flow velocity contribution on the total pollutant dispersion process, two series of numerical simulations were performed: with the dispersion coefficients values depending on the flow velocity and dispersion coefficient values, which are independent on the river flow velocity. All mentioned simulations were performed at two hydrologic conditions: annual discharge (Qa) along the modelled river part and with the nearby minimum flow situation (Q355). Achieved results confirm relatively high model sensitivity on input values of dispersion coefficients. The influence rate is discussed in this paper and documented in figures.
  
  KEY WORDS: dispersion, surface stream, numerical model, MIKE
  
  Address:
  - Yvetta Velísková, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:00421 2 49268 280 Fax.: 00421 2 44259 404 Email: veliskova@uh.savba.sk)
  - Marek Sokáč, Stavebná fakulta STU Katedra zdravotného a environmentálneho inžinierstva, Radlinského 11 813 68 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 219 - 226, doi:
Scientific Paper, Slovak

Renáta Dulovičová, Yvetta Velísková: Aggradation changes at Žitny ostrov channels

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• Aggradation changes at žitny ostrov channels. The article deals with the changes in silting of selected channels at Žitný ostrov for the period from 1993 through 2004 and 2008. Measurements of bottom silts in 1993 were done on channels Aszód, Gabčíkovo-Topoľníky, Komárňanský channel, Aszód-Čergov, Čergov-Komárno, Čalovo-Holiare and Holiare-Kosihy. In 2004 the control measurements were done on channels Aszód, Gabčíkovo-Topoľníky and Komárňanský channel, at least in three control profiles for each of these aforementioned channels.These measurements shown that for the period since 1993 to 2004 was generally rather to increase the silt layer size. The increase of bottom silts in Komárňanský channel is documented by values of their volumes for section from 4.0 to 26.0 km - in Table 2. As an example of changes in the silt-layer size on the above-mentioned channels are the cross-channel profiles at Gabčíkovo-Topoľníky in km 29,9, which was also measured in detail in 1993 and in 2004 - Figure 8. In 2008 there were repeated the measurements of bottom silts in detail at the channel Gabčíkovo-Topoľníky. Table 3 documents the increase of the volume of bottom silts in 2008, also at this channel compared to its recorded in 1993. Examples of changes in cross sections by influence of silting at channels Aszód, Gabčíkovo-Topoľníky and Komárňanský channel are illustrated in Fig. 6, 7, 8.
  
  KEY WORDS: sedimentary processes, channel network, surface and ground water interaction, open channel
  
  Address:
  - Renáta Dulovičová, Ústav hydrológie SAV Račianska 75, 838 11 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 49268280 Fax.: Email: dulovicova@uh.savba.sk)
  - Yvetta Velísková, Ústav hydrológie SAV Račianska 75, 838 11 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 227 - 233, doi:
Scientific Paper, Slovak

Emília Šebová, Renáta Dulovičová, Yvetta Velísková: Comparison of discharge measurements with current meter and digital equipment Flow-tracker

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• This paper deals with two ways of measurement of velocity profile and discharge in natural stream. There were used two ways: discharge measurement with the propellor current meter and the discharge measurement with the equipment FlowTracker. This equipment has 2D or 3D probe and it is based on application of Doppler principle. There were selected three profiles at the Vydrica stream, location Bratislava – Železná studnička. For the determination of discharge, we used two methods by ISO 748 (1997) a 9196 (1992): the Mid-section method and the Mean-section method. The aim was to compare this two ways of measurement and also to compare the used method.
  
  KEY WORDS: total discharge, current meter, FlowTracker, Mid-section method, Mean-section method, Doppler principle
  
  Address:
  - Emília Šebová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+421249268280 Fax.: Email: sebova@uh.savba.sk)
  - Renáta Dulovičová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Yvetta Velísková, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 234 - 245, doi:
Scientific Paper, Slovak

František Burger: Analysis of characteristics of quasi-steady state of the riverine area subsurface water at average water level of Danube and Vah river.

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• The aim of this study is to analyze the basic characteristics of the quasi-state groundwater and soil water status of the Danube and the lower Vah riverine territory, at their average state in water levels on 7 August 2002 after stopping the construction of dam but after construction of the Waterwork Nagymaros protective measures on the Slovak territory. The basic characteristics include the location of groundwater level, depth below ground surface level and velocity vectors of groundwater movement. Aeration zone area is characterized by the total amount of unsaturated porous media and the volume of soil water in the aeration zone. Basic characteristics of the quasi-state status are derived from developed numerical models of the riverine territory. The results of numerical model simulations shows that if the protective measures did not be implemented, so at the average water level of rivers, the maximum change in position of groundwater level was from +0.41 m to -0.49 m. Maximum level position changes should have occurred along the route of underground sealing wall (PTS). The installation of protective measures in the section of Komarno - Patince (after pumping station), cause the flow from riverine aquifer to the Danube decreased on 97.4%.
  
  KEY WORDS: subsurface water, Danube Basin, protective measures, reservoir Nagymaros, numerical models
  
  Address:
  - František Burger, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+ 421 2 49268 254 Fax.: + 421 2 44259 404 Email: burger@uh.savba.sk)

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 246 - 250, doi:
Scientific Paper, Slovak

Karol Kosorin: Coefficient of longituginal dispersion for mathematical models of contaminant transport in rivers and channels at unsteady water regime

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• The dispersion coefficient D [m2.s-1] is key input parameter for mathematical modeling of contaminant transport in rivers and channels by equation (1). Of course, determination of D with sufficient correctness still meets difficulties even for steady water flows, see Fisher (1964, 1967), Kosorin (1995) or Říha et al (2000). Moreover these problems rise if one needs to apply D for unsteady flow defined by the shallow water equations (2). There is not sufficient to use a constant value of D because of its dependency on total flow dynamics and hydraulic parameter of river/channel bed. The study treat the above problems and presents the way how to find the representation values of D for steady flows as well as the solution for unsteady water flows in the form of analytical dependency on water velocity and hydraulic parameters of streams. The given solution of the problems consists of two items. The first one is the assumption of existence of at least one value of D stated e.g. up on tracing experiments with of contaminant concentrations c(t) indicated at suitable river/channels profiles. The second one is the analytical dependency of D on mean water velocity and hydraulic characteristics of water stream. This dependency (11) has been based on the Fisher (1966) integral with numerical coefficient derived from known value of D.
  
  KEY WORDS: longitudinal dispersion, mathematical modeling of solutes transport in unsteady streams, dispersion coefficient, tracer experiments
  
  Address:
  - Karol Kosorin, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 49268280 Fax.: +4212 44259404 Email: kosorin@uh.savba.sk)

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 251 - 258, doi:
Scientific Paper, Slovak

Peter Kyrinovič, Ján Erdélyi, Aloiz Kopáčik: Effective application of 3d model for the flood protection object within area using terrestrial laser scanning technology

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• The 3D model of the object builds an important base for their design. The application of the terrestrial laser scanning technology builds an effective form of 3D model creation. The paper give complex overview of tasks connected with 3D model creation of the Holombek II polder, which is located in the cadaster of Modra city.
  
  KEY WORDS: flood-protection, polder, terrestrial laser scanning, scanner, 3D model
  
  Address:
  - Peter Kyrinovič, STU – Stavebná fakulta Radlinského 11 813 68 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: peter.kyrinovic@stuba.sk)
  - Ján Erdélyi, STU – Stavebná fakulta Radlinského 11 813 68 Bratislava, Slovenská republika
  - Aloiz Kopáčik, STU – Stavebná fakulta Radlinského 11 813 68 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 259 - 266, doi:
Scientific Paper, Slovak

, Ladislav Holko, Zdeněk Kostka: Estimation of the mean transit times using isotopes and hydrograph recessions

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• In this paper is estimated to calculation of mean transit time (MTT) in three catchments – the Jalovecký creek-mountains catchment (22km2), the whole Jalovecký creek catchment (45km2), and the upper Váh river catchment (1095km2). Two methods based on stable isotopes (18O) and one based on hydrograph analysis were used to compute MTT. Isotopic methods gave comparable results (MTT computed by the sine curve method was 1-3months shorter than that computed by the lumped model). MTT estimated for the larger catchments using hydrograph analysis (longer recession), was much longer than one calculated from 18O, for the smallest catchment the shorter recession gave us much shorter value of MTT than 18O. The length of the data series used in MTT calculations by means of 18O did not influence results of calculation.
  
  KEY WORDS: isotopes, transit time, mountain catchment, hydrograph
  
  Address:
  - Michal Dóša, - Ladislav Holko, Ústav hydrológie SAV Experimentálna hydrologická základňa Ondrašovecká 16 031 05 Liptovský Mikuláš, Slovenská republika
  - Zdeněk Kostka, Ústav hydrológie SAV Experimentálna hydrologická základňa Ondrašovecká 16 031 05 Liptovský Mikuláš, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 267 - 273, doi:
Scientific Paper, Slovak

Mária Martincová, Pavla Pekárová: Identification of changes in number of extreme floods and droughts in the Bela river daily discharge

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• This paper is devoted to changes in number of extreme floods and changes in duration of extreme low flows in the measured daily flow data series. First part of the paper is focused on description of the Indicators of Hydrologic Alternations (IHA) software. This software was used for statistical evaluation of changes in number of small, medium and large floods, as well as extreme low flows. Changes of daily flows during the period of hydrological years 1928/29–2007/08 on the Bela River at Podbanske station are presented in the second part of the paper. The Bela basin up to Podbanske is part of the Tatra National Park (TANAP) with the highest degree of protection and with a minor anthropogenic impact. Therefore it is suitable for the study of the effect of higher air temperature on runoff. The results shows, that there were no important changes in number of extreme floods and no extent of droughts on the Bela River during the study period.
  
  KEY WORDS: climate change, floods, low flows, Bela River basin
  
  Address:
  - Mária Martincová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:004212 44259311 Fax.: 004212 44259311 Email: martincova@uh.savba.sk)
  - Pavla Pekárová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 274 - 281, doi:
Scientific Paper, Slovak

Pavla Pekárová, Pavol Miklánek, Dana Halmová: Database of the mean daily and extreme annual discharges in the Danube river basin.

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• The territory of the Danube River Basin is one of the most flood-endangered regions in Europe. Therefore there is a strong need to have complete and exhausting information on the flood regime in order to be able to generalize such information on the basis of long-term observations from the whole Danube territory. The mean daily discharge and annual peaks Qmax as well, were collected from Danube River and its tributaries from period 1931–2005 (1901–2008, and more, optionally). This information can be used for water management and design of flood control structures and for improvement of the methodological base of institutions and agencies responsible for flood warnings.
  
  KEY WORDS: Danube River basin, daily and annual peak discharges, database
  
  Address:
  - Pavla Pekárová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:004212 44259311 Fax.: 004212 44259311 Email: pekarova@uh.savba.sk)
  - Pavol Miklánek, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Dana Halmová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 282 - 290, doi:
Scientific Paper, Slovak

Pavla Pekárová, Pavol Miklánek, Ján Pekár: Possibilities of the long-term flow forecast of the Slovak rivers using the North-Atlantic Oscillation Index NAOI

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• The paper deals with the analysis of the long-term trends and possibilities of the long-term flow forecast of the Slovak rivers using the winter North-Atlantic Oscillation Index. The year 2010 was extremely wet with many catastrophic floods in the Central Europe. The value of the winter NAO index in this year (average of the months December 2009–March 2010) was extraordinary low, only –2.85. The statistical analyses show, that during the periods with positive winter NAOI are the flows of the Slovak rivers lower. The years with negative winter NAOI are much moister.
  
  KEY WORDS: North-Atlantic Oscillation, winter NAO index, cross-correlation, long-term discharge prognosis
  
  Address:
  - Pavla Pekárová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:004212 44259311 Fax.: 004212 44259311 Email: pekarova@uh.savba.sk)
  - Pavol Miklánek, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Ján Pekár, Katedra aplikovanej matematiky a štatistiky Fakulta matematiky, fyziky a informatiky UK Mlynská dolina 842 48 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 291 - 301, doi:
Scientific Paper, Slovak

Ladislav Gaál, Silvia Kohnová, Ján Szolgay: Application of Bayesian MCMC methods for inclusion of historical floods in a statistical estimation of design maximum floods

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• The presented work deals with temporal data extension for the purposes of a local frequency analysis. The method consists in inclusion of historical hydrological events into the procedure of flood quantile estimation. The statistical modelling takes the advantage of Monte Carlo Markov chain simulations, which, within a Bayesian framework, represent a flexible tool for an inclusion of hydrological information of different origin. The practical aspects of Bayesian MCMC simulations are demonstrated through a case study that focuses on the Myjava River at the cross-section Myjava. Two considerably high flood peaks that appeared in the local series of observations are considered as ‘historical’ events, and we examine the results of the frequency analysis depending on whether i) these two exceptional events are fully excluded from the data sample; whether ii) the whole series of observations is analyzed or iii) the two discussed flood peaks are regarded as historical events. The study suggests that the most acceptable results of the frequency analysis (i.e., the narrowest confidence intervals of the 100-year flood quantiles) are related to the last option, which adopts the concept of inclusion of historical events.
  
  KEY WORDS: flood peaks, frequency analysis, confidence interval, historical events, Monte Carlo Markov chains, Bayesian approach
  
  Address:
  - Ladislav Gaál, KVHK SvF STU v Bratislave Radlinského 11 813 68 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 59 274 727 Fax.: +4212 59 274 499 Email: ladislav.gaal@stuba.sk)
  - Silvia Kohnová, KVHK SvF STU v Bratislave Radlinského 11 813 68 Bratislava, Slovenská republika
  - Ján Szolgay, KVHK SvF STU v Bratislave Radlinského 11 813 68 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 302 - 309, doi:
Scientific Paper, Slovak

Miroslava Tegelhoffová: The analysis of mean monthly water discharges on hydrologic station Banska Bystrica

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• The main purpose were the analyses of mean monthly water discharges on hydrologic station Banska Bystrica during the period 1931-2008. We were monitoring flow regime. The monitored data we divided into same periods of 15 years, the last period had 18 years. The most wet months were April and May. The most dry months were February, August and September. In the next step we detected the linear trend in each month, where ensued in each month is non marked decreasing trend. Moreover we detected the wateriness of the river, deflections mean annual water discharges from long term annual mean water discharge. Then we described them in program Surfer. The driest years were occurred along the years 1971-1974, 1985-1990, and 2000-2008. The most wet years were occurred along the years 1935-1941. In the middle of monitoring period we were detected the changing of wet and dry periods. Dry periods have the tendency to occur from August till December. In the years 1936-1941 the wet periods were occurred from August till December. In following periods in the same months were wet period replaced by dry period.
  
  KEY WORDS: water discharges, water fluctuation, precipitation, trend analysis, climate change, hydrology
  
  Address:
  - Miroslava Tegelhoffová, Katedra vodného hospodárstva krajiny Stavebná fakulta Slovenská technická univerzita v Bratislave Radlinského 11 83102 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: mirkategel@yahoo.com)

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 310 - 317, doi:
Scientific Paper, Slovak

Milan Čistý, Zbyněk Bajtek: Irrigation network design using two-phase multiobjective optimization

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• A water distribution network is a system containing pipes, reservoirs, pumps, and valves of different types, which are connected to each other to provide water to consumers. In the case of the design of a pipe network the optimization problem can be stated as follows: minimize the cost of the network components subject to the satisfactory performance of the water distribution system (mainly, the satisfaction of the allowable pressures in demand nodes). This leads to difficult constrained combinatorial optimization problem to which various algorithms ranging from mathematic programming, heuristic methods or artificial intelligence have been applied. In this article we try to highlight disadvantages of current solutions, mostly from the perspective their ability to obtain solutions which are close to the global optimum. Article describes new multiphase and multicriterial methodology based on NSGA- II algorithm which use simulation model EPANET. This new method was applied on relatively large irrigation network and the results obtained provide promising improvement according to already presented results in scientific literature.
  
  KEY WORDS: heuristic algorithm, irrigation networks, two-phase multicriterial optimization
  
  Address:
  - Milan Čistý, Katedra vodného hospodárstva krajiny Stavebná fakulta STU v Bratislave Radlinského 11 813 68 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: milan.cisty@stuba.sk)
  - Zbyněk Bajtek, Katedra vodného hospodárstva krajiny Stavebná fakulta STU v Bratislave Radlinského 11 813 68 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 318 - 327, doi:
Scientific Paper, Slovak

Justína Vitková, Jana Skalová: Analyse of simulated soil water storage by using different meteorological inputs

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• Simulation models are very often used for assess the impact of climate changes on soil water regime. However we don’t have always the necessary input meteorological data. Therefore in this paper we evaluated outputs of the simulation model using different meteorological input data. We compared outputs of soil water storage for grass in three soil layers for two simulations. The first simulation was made by using real measured daily values of all meteorological characteristics. The second simulation was made by using the calculated average monthly data of the monitoring period for wind velocity and sunshine duration. Results showed that differences in outputs of soil water storage in all soil layers are minimal. And it means that calculated average monthly data for wind velocity and sunshine duration as meteorological inputs can be used for forecast the characteristics of soil water regime due to climate changes, if there are not measured daily data.
  
  KEY WORDS: soil water storage, mathematical model, wind velocity, sunshine durat
  
  Address:
  - Justína Vitková, KVHK, SvF, STU Radlinského 11 813 68 Bratislava 1, Slovenská republika (Corresponding author. Tel.:+4212 59274622 Fax.: +4212 52923575 Email: justina.vitkova@stuba.sk)
  - Jana Skalová, KVHK, SvF, STU Radlinského 11 813 68 Bratislava 1, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 328 - 337, doi:
Scientific Paper, Slovak

Marek Rodný, Viliam Nagy, Vlasta Štekauerová: Applications of feedforward neural networks to soil water dynamics modeling of a floodplain forest

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• Mathematical modeling of the soil water regime is often used as an alternative to direct soil moisture surveys. Potential of data driven models in the soil water diagnostics issues is poorly reported yet. Therefore objectives of this study are to explore the applicability of the artificial neural network based algorithms in development of soil water content database of a floodplain forest ecosystem. It is hypothesized that water balance can be modeled with artificial neural networks, in somehow abstract manner, based on meteorological indices of antecedent precipitation and temperature. Analytic part of the study describes linkage between the model uncertainties and quality of data used in artificial intelligent learning processes. Based on statistical evaluation we can conclude that neural networks together with meteorological indices can be used for soil water dynamics modeling with an average error (RMSE) 20mm. Furthermore, error results clearly show that from original 150 calibration days only 30% (40 days) are really needed for sufficient model calibration.
  
  KEY WORDS: soil water regime, neural network, mathematical modeling
  
  Address:
  - Marek Rodný, Ústav hydrológie, Slovenská akadémia vied, Račianska 75, 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: rodny@uh.savba.sk)
  - Viliam Nagy, Ústav hydrológie, Slovenská akadémia vied, Račianska 75, 831 02 Bratislava, Slovenská republika
  - Vlasta Štekauerová, Ústav hydrológie, Slovenská akadémia vied, Račianska 75, 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 338 - 344, doi:
Scientific Paper, Slovak

Tomáš Orfánus, Pavel Dlapa, Nándor Fodor, Kálman Rajkai, Zoltán Bedrna: Comparison of hydraulic characteristics of sandy soil under meadow in Sekule (Slovakia) and under fallow land in Őrbottyán (Hungary)

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• Under high temperature and low water content, the wettability of organic substances, which cover soil particles, decreases and the infiltration process is retarded or even entirely prevented. The objective of this study was to quantify the effect of different soil treatment on soil hydraulic characteristics (saturated KS and nearly-saturated k(h0 =-2cm) hydraulic conductivity, sorptivity S, apparent contact angle a, water drop penetration time test, water repellency index R) at two locations in Pannonian basin; Sekule in south-western Slovakia and Őrbottyán in northern Hungary. Both are sandy soils differing by land use and presence of carbonates. The first is an untreated meadow while the other is former arable land containing natural as well as after-fertilization residual contents of carbonates. As the reference material, the aeolian sand with no organic matter and no carbonates from locality Sekule was taken. The results show that after prolonged dry seasons the infiltration is generally retarded in sandy soils, which contain organic matter when compared to both, reference material and ethanol infiltration. This is due to increase of wetting angle. In arable soil the effect was partially alleviated by the presence of carbonates. This hypothesis was supported by laboratory experiments with the meadow soil from Sekule, when after calcite addition into the soil the persistence of water repellency has decreased significantly.
  
  KEY WORDS: infiltration, hydraulic characteristics, water repellency
  
  Address:
  - Tomáš Orfánus, Ústav hydrológie Slovenskej akadémie vied Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 49268279 Fax.: +4212 44259404 Email: orfanus@uh.savba.sk)
  - Pavel Dlapa, Univerzita Komenského Prírodovedecká fakulta Katedra pedológie Mlynská dolina 842 15 Bratislava, Slovenská republika
  - Nándor Fodor, Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences Herman Ottó út. 24 1022 Budapest, Hungary
  - Kálman Rajkai, Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences Herman Ottó út. 24 1022 Budapest, Hungary
  - Zoltán Bedrna, Univerzita Komenského Prírodovedecká fakulta Katedra pedológie Mlynská dolina 842 15 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 345 - 348, doi:
Scientific Paper, Slovak

Vlasta Štekauerová, Július Šútor, Viliam Nagy, Katarína Brezianská: Measuring of saturated hydraulic conductivity by disc permeameter

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• Unsaturated soil zone is one of the most important and for evaluation of water movement the most complicated part of the hydrological cycle. Water supplies in this part of the soil, which determine its production capacity, depend on the inflow and outflow water to or from the unsaturated soil. These water flows in the soil depend on the saturated hydraulic conductivity. In real soil can be distinguished conductivity of soil matrix and conductivity of preferred ways. Disc permeameter is suitable for determining the conductivity of soil matrix.
  
  KEY WORDS: soil, hydraulic conductivity coefficient, disc permeameter
  
  Address:
  - Vlasta Štekauerová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 44259 404 Fax.: +4212 44259 404 Email: stekauer@uh.savba.sk)
  - Július Šútor, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Viliam Nagy, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Katarína Brezianská, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 349 - 352, doi:
Scientific Paper, Slovak

Vlasta Štekauerová, Július Šútor, Viliam Nagy, Katarína Brezianská: Measuring of saturated hydraulic conductivity by Guelph permeameter

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• Water soil speed racing is strongly influenced by the presence of preferred pathways in the soil, which the water flows faster than by the soil matrix. The presence of preferred pathways most affects the value of saturated hydraulic conductivity K. The value K measured in the soil, which does not contain the preferred path, characterizes direct conductivity of matrix. In natural conditions, the occurrence of preferential pathways is natural and therefore in many cases, the measured value of K characterizes the conductivity of the preferred pathways rather than the matrix conductivity. Guelph permeameter is experimental field methods suitable for determining the conductivity of real soils.
  
  KEY WORDS: soil, hydraulic conductivity coefficient, Guelph permeameter
  
  Address:
  - Vlasta Štekauerová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 44259 404 Fax.: +4212 44259 404 Email: stekauer@uh.savba.sk)
  - Július Šútor, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Viliam Nagy, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Katarína Brezianská, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 353 - 356, doi:
Scientific Paper, Slovak

Vlasta Štekauerová, Július Šútor, Viliam Nagy, Peter Šurda, Marek Rodný: Measuring of drainage branche of water retention curves by overpressure equipment

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• Basic hydrophysicalal characteristic of the soil is soil water retention curve, which expresses the relationship between soil moisture content ? and soil water potential hw in steady state. It expresses the relationship between energy status of water in the soil and amounts of water in the soil. Water retention curve is widely used. It is preferred to use its analytical expression, which can be obtained from the measured water retention curve points. The measurement of these points can be made on overpressure equipment.
  
  KEY WORDS: soil, water retention curve, pressure equipment
  
  Address:
  - Vlasta Štekauerová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 44259 404 Fax.: +4212 44259 404 Email: stekauer@uh.savba.sk)
  - Július Šútor, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Viliam Nagy, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Peter Šurda, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Marek Rodný, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 357 - 364, doi:
Scientific Paper, Slovak

Július Šútor, Vlasta Štekauerová: Effect of soil types on their water retention

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• Water storage in the unsaturated soil zone is the available water supply for agricultural and forest ecosystems, which determines their existence. In other words, ecosystems indicate the reliability, resilience and vulnerability of the water source area, the integral impact of meteorological phenomena, vegetation cover, ground water level, civil engineering and water management arrangements, and the origin of any kind, conducted in the area of interest. Real water supply in the active zone of unsaturated soil horizon is quantified by direct monitoring, and potential reserves calculation procedure using the water retention lines of soil types. In the present article we present the results of monitoring of water supplies in six soil types, climatic and meteorological conditions of Rye Island in 1994 (from relevant sites) To determine the effect of soil type on the retention of water were used datasets obtained by direct monitoring at 17 locations Rye island in 1994. Deployment of monitoring sites in the Rye Island followed a cross-cutting Biskupické rameno - Šamorín - Baka - Baloň.
  
  KEY WORDS: water storage, soil, water retention curve
  
  Address:
  - Július Šútor, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 44259383 Fax.: +4212 44259404 Email: sutor@uh.savba.sk)
  - Vlasta Štekauerová, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 365 - 374, doi:
Scientific Paper, Slovak

Štefan Rehák, Július Šútor, Peter Stradiot: Dynamics of water supply in the soil profile structural border

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• Dynamics of water supply in the soil profile structural border..The water regime in the soil aeration zone is determined by the position of the soil profile in relief, climatic conditions, hydrological properties of soil, participation of ground water in water balance of the aeration zone, and vegetation cover. In the upper part of Zitny ostrov, the position of soil profile in the subsurface layer of lithosphere plays a dominant role in creation of the water supply in the aeration zone. The soil cover layer is laid on gravel basement thus forming structural interface. This interface plays a significant role in creation and dynamics of water supplies in the aeration zone of soil in selected localities of Zitny ostrov, respectively in hydrology of subsurface water of the above-mentioned region. Presented study is oriented to problem of water regime of the soil aeration zone in two selected localities of upper Zitny ostrov, where water regime is influenced gravel interface in the depth of ca. 100 cm. For those conditions there is presented characteristic distribution of moisture on the height of soil profile and course of water supply in the aeration zone for years of organized monitoring.
  
  KEY WORDS: structural interface, monitoring of soil moisture, soil moisture regime
  
  Address:
  - Štefan Rehák, Výskumný ústav vodného hospodárstva Nábr. Arm.gen.L.Svobodu 5 812 49 Bratislava, Slovenská republika (Corresponding author. Tel.:+4212 59343377 Fax.: Email: rehak@vuvh.sk)
  - Július Šútor, Ústav hydrológie SAV Račianska 75 831 02 Bratislava, Slovenská republika
  - Peter Stradiot, Výskumný ústav vodného hospodárstva Nábr. Arm.gen.L.Svobodu 5 812 49 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 11, No. 2, 2010, p. 375 - 381, doi:
Scientific Paper, Slovak

Dušan Igaz, Ján Čimo, Ján Horák: Evaluation of drought occurrence in the conditions of Danubian upland

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• The article is focused on evaluation of soil drought which is defined by decrease of soil moisture below the value of wilting point (qWP). The course of soil moisture has been measured for the time period of years 1989 - 2003 at the site of Nitra which represents the northern part of Danubian upland. In the paper, there were analyzed soil moistures measured using the gravimetric method at the soil depths of 0,1; 0,3 and 0,5 m. The measured data showed that a soil moisture decrease below qWP at the depth of 0,1 m with a probability of 50% and 80% occurred during 60 and 40 days of growing season, respectively. Achievement, or excess of the soil moisture value below the qWP at the depth of 0,3 m with a the probability of 50% and 80% occurred during 40 and 23 days, and for the depth of 0,5 m, it was equal to zero for both probabilities. At 20% probability it was approximately 12 days.
  
  KEY WORDS: soil moisture, wilting point, soil moisture monitoring
  
  Address:
  - Dušan Igaz, Slovak University of Agriculture in Nitra Horticulture and Landscape Engineering Faculty Department of Biometeorology and Hydrology Hospodárska 7 94901 Nitra, Slovak Republic (Corresponding author. Tel.: Fax.: Email: dusan.igaz@uniag.sk)
  - Ján Čimo, Slovak University of Agriculture in Nitra Horticulture and Landscape Engineering Faculty Department of Biometeorology and Hydrology Hospodárska 7 94901 Nitra, Slovak Republic
  - Ján Horák, Slovak University of Agriculture in Nitra Horticulture and Landscape Engineering Faculty Department of Biometeorology and Hydrology Hospodárska 7 94901 Nitra, Slovak Republic