Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 3 - 14, doi:
Scientific Paper, Slovak

Danuše Szőkeová, Silvia Kohnová: Modelling of mean monthly discharges with application of SETAR and LSTAR models

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• The modelling and forecasting of flows is very important problem for reservoir management. Time series analysis based on past records from Slovak stream-gaugin stations is used for building mathematical models and simulation in hydrology. In this paper we made analysis of discharge time series obtained at the stations Banská Bystrica (Hron), Moravský Ján (Morava) and Lekárovce (Uh) in the period 1961 to 2000. At first we have created systematical function to describe trends and cycles in the data. Then we have applied the SETAR and LSTAR regime switching model class for modelling systematic function residual time series and we have created additive discharge models. The aim was to test profitability of regime switching models for modelling and simulation water discharge time series.
  
  KEY WORDS: mean monthly discharges, systematic function, SETAR and LSTAR regime switching models, monthly discharge additive models
  
  Address:
  - Danuše Szőkeová, Katedra ekonómie a financií, Fakulta managementu Univerzity Komenského v Bratislave, Odbojárov 10, 820 05 Bratislava 25, Slovenská republika 820 05 Bratislava 25
  - Silvia Kohnová, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: silvia.kohnova@stuba.sk)

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 15 - 22, doi:
Scientific Paper, Slovak

Romana Marková, Silvia Kohnová, Gabriel Földes: Seasonality and decadal changes analysis of the maximum annual peak-discharge series in guaging stations located in the Slovak-Polish area of the Carpathian mountains

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• The aim of the study was the examination of the seasonality of flooding across Slovak-Polish part of the Carpathian Mountain using directional statistics. Flooding in the Carpathian Mountains has some of its most serious impacts on settlement, transportation and agriculture. Floods are generated by prolonged heavy rainfall, snowmelt or both. Processed gauging stations are located in Slovak-Polish area of the Carpathian Mountains. Together there were processed 169 stream gauging stations, specifically 41 Slovakian stations and 128 Polish gauging stations. Within the seasonality there was analyzed the whole observed period with different length of maximum annual peak-discharge series for each stream gauging station, with the length of maximum annual peak-discharge series from 34 to 88 years for Slovakian stream gauging stations and with the length of maximum annual peak-discharge series from 10 to 59 years for Polish stream gauging stations. The analysis was also processed for three, five and ten largest annual maximum discharges. Seasonality results were spatially displayed for better understanding of their causes and seasonality analysis for different decades were processed tabular for more accurate analysis of flood occurrence. The results showed that the floods in the Slovak-Polish area of the Carpathian Mountains occur mostly in the summer months of May, June and July and they may be due to convective rainfall, causing torrential rains, or by snowmelt in the High Tatras.
  
  KEY WORDS: directional statistics, Carpathian Mountains, floods
  
  Address:
  - Romana Marková, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: romana.markova@stuba.sk)
  - Silvia Kohnová, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika
  - Gabriel Földes, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 23 - 30, doi:
Scientific Paper, Slovak

Patrik Sleziak, Kamila Hlavčová, Ján Szolgay, Juraj Parajka: Dependence of the quality of runoff-simulation by a rainfall-runoff model on the differences in hydroclimatic conditions of calibration and validation period

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• The present study deals with the parametrization of the rainfall-runoff (r-r) model (TUW model) in a changing climate conditions. TUW model was calibrated in period 1981 – 1990 and validated in period 2001 – 2010 for two different groups of Austrian catchments (catchments with dominant snow and rainfall-runoff regime). Model parametrization was carried out by combination of the Nash-Sutcliffe coefficient (NSE) and the logarithmic Nash-Sutcliffe coefficient (logNSE). The model efficiency was evaluated in terms of volume error (VE). We have identified two clusters of catchments in which the values of volume error was the most significant (lower or higher values). This is demonstrated on the simulations of the mean monthly flows for the selected catchment from each cluster, which also represents different runoff regime. In the case of the catchment with dominant snow-runoff regime, with a change in air temperature 1.5 – 2 °C the model significantly underestimated mean monthly flows (19 %). To the contrary, in the catchment with dominant rainfall-runoff regime, with a change in precipitation (20 – 30 %), the model significantly overestimated mean monthly flows (25 %). For the practical applicability of R-R models it would be suitable to consider various calibration periods and to change the model parameters depending on the hydroclimatic regime.
  
  KEY WORDS: TUW model, model parametrization, volume error, climatic conditions
  
  Address:
  - Patrik Sleziak, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: patrik.sleziak@stuba.sk)
  - Kamila Hlavčová, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika
  - Ján Szolgay, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika
  - Juraj Parajka, Institute of Hydraulic Engineering and Water Resource Management, Vienna University of Tehchnology, Karlsplatz 13/222, A-1040 Vienna, Austria

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 31 - 38, doi:
Scientific Paper, Slovak

Danka Grambličková, Emília Bednárová, Juraj Škvarka, Vladimír Chrobák: Design, assessment and remediation of the left flood protection dike of the River Váh in km 23,040 – 27,075

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• The left-side section of the River Váh protection dike in km 23,040 – 27,075 provide flood protection of the area between Komoča municipality and Kolárovo town which are located in the south-western part of Slovakia. During flood flows in the Vah River there were repeatedly monitored phenomena indicating the existence of risk factors in the body and in the subsoil of the protection dike. In 2009, these facts were an impulse for remedial action design followed by elaboration of the project and the implementation of the proposed remediation in the period of May - December 2013. This article focuses its attention mainly on the design and impact assessment of the remedial actions of the left dyke’s stability and adjacent area. The problem was solved by the finite element method. The article also partially focuses its attention to the phase of the remedial action implementation.
  
  KEY WORDS: flood protection dyke, subsoil, filtration velocity, filtration stability, uplift, remediation measures, finite element method
  
  Address:
  - Danka Grambličková, Katedra geotechniky, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 810 05 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: danka.gramblickova@stuba.sk)
  - Emília Bednárová, Katedra geotechniky, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 810 05 Bratislava, Slovenská republika
  - Juraj Škvarka, Katedra geotechniky, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 810 05 Bratislava, Slovenská republika
  - Vladimír Chrobák, Slovenský vodohospodársky podnik, š.p., OZ Bratislava, Karloveská 2, 841 04 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 39 - 48, doi:
Scientific Paper, Slovak

Cyril Siman, Yvetta Velísková: Pollution transport in surface streams – elementary terms and principles of modeling

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• Presence of water in liquid state is, together with oxygen in atmosphere, elementary condition of life in the world. For human, but also for others organisms, is necessary that water was suitable for drinking without risk of damage. Water quality in Slovakia, but in others countries of the world has decreased during the 20th century. In some countries of the world this trend continues even today, but for example the quality of water in some river parts at Slovakia territory, has generally improved after 1989 Performed measures only mitigate human impact on the water quality. It’s mainly due to population density increasing and urbanization along rivers, also due to excessive and unnatural exploitation of water sources, as well. While in the past, point sources of pollution was considered like the biggest source of pollution in surface streams, after the installation of treatments plants of urban and industrial waste water, nonpoint - diffuse sources of pollution happened like the important source of pollution in river basin. Pollution from both types of pollution sources often gets to surface streams. After entry of pollutant to surface streams, mixing processes start. These processes are divided into four stages, while the concentration of pollution in streams going to lower, as well. The article includes basic information relating with problems of water quality and spreading of pollution in surface streams. It explains elementary relations, terms and mechanisms of pollution transport in surface streams.
  
  KEY WORDS: water quality, pollution, surface streams, mixing, dispersion, advection
  
  Address:
  - Cyril Siman, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: siman@uh.savba.sk)
  - Yvetta Velísková, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 49 - 56, doi:
Scientific Paper, English

Marek Sokáč, Yvetta Velísková: Localization of pollution sources – inverse task in pollution transport

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• Paper describes the current knowledge and possible methods to solve the inverse task of the pollution transport in watercourses. Inverse pollution transport task in watercourses arises in cases when place of the pollution entry into a watercourse is unknown (e.g. breakdown pollution leakage, ecological accident along a watercourse), but we know the pollution concentration time course in the monitoring profile. Solutions of such defined task are characterized by a high degree of uncertainty because the boundary conditions are not known: besides that, pollution source location is unknown, discharged amount of pollutant and the time course of the pollutant concentration in the efflux are unknown or unclear, as well. Problematic can be also to determine the hydraulic conditions in a watercourse as well as the dispersion parameters. Paper contains a definition of inverse task, brief description and categorisation of the methods used for solving inverse problems of pollution transport in watercourses, as well as the analysis of the problems and errors arising in solving of inverse tasks and proposed solution concept.
  
  KEY WORDS: pollution source, localisation, inverse task, on-line monitoring, dispersion, watercourse
  
  Address:
  - Marek Sokáč, Katedra zdravotného a environmentálneho inžinierstva, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 810 05 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: marek.sokac@stuba.sk)
  - Yvetta Velísková, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 57 - 67, doi:
Scientific Paper, Slovak

Viera Kováčová: Trends of nitrate ions content in Žitný ostrov channel network

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• Anthropogenic activities realized in river basins may result in a deterioration of water quality with detrimental effects on the ecosystems. Nitrate leaching from agricultural land is usually considered a non-point source pollution problem, making the specific polluter hard to identify. The Žitný ostrov is one of the most productive agricultural areas of Slovakia, situated on the Danube Lowland. Under its surface is the richest water source of Slovakia. For this reason, it is very important to deal with quantity and quality of water resources in this region. Many practices result in non-point source pollution of groundwater and the effects of these practices accumulate over time. These sources include fertilizer and manure applications, dissolved nitrogen in precipitation, irrigation flows, and dry atmospheric deposition. Numerous studies have suggested that leaching of NO3- following high input rates of chemical fertilizer and due to mineralization of organic N already present in the soils can cause degradation of surface and groundwater quality. Directive 2000/60/EC sets out general provisions for the protection and conservation of groundwater. Measures to prevent and control groundwater pollution should be adopted, including criteria for assessing good groundwater chemical status and criteria for the identification of significant and sustained upward trends of water quality and for the definition of starting points for trend reversals. The study is focused on identification of the long-term trends in the surface water quality in channel network on Žitný ostrov. The paper shows changes in measured values of nitrates in particular channels in years 1987 – 2016. It was shown the channel water quality has been changed significantly during the period 1987 – 1991, after 1991 is slightly decreased.
  
  KEY WORDS: nitrate ions, surface water quality, nitrogen compounds pollution
  
  Address:
  - Viera Kováčová, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: kovacova@uh.savba.sk)

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 68 - 75, doi:
Scientific Paper, English

Dana Kotorová, Ladislav Kováč: Different soil tillage in relation to water storage in profile of heavy soils

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• The aim of this contribution was evaluation of water storage in profile of clay-loamy Gleyic Fluvisol. In field treatment between 2011 and 2016 years, the effect of conventional tillage and no-tillage technologies on maximum, average and minimum soil water storage were observed. Soil samples for the determination of water storage were taken from profile 0.0 – 0.3 m, respectively 0.0 – 0.8 m from both tillage variants. Monitoring was realised during vegetation season at two-week intervals. Obtained contents of soil water storage were re-counted at maximum soil water storage on percent of moisture of field water capacity, at average soil water storage on percent of moisture of point of decreased availability and at minimum soil water storage on percent of moisture of wilting point. Maximum, average and minimum soil water storages, in both observed depth, were significantly influenced by used tillage technology and experimental year. More significant was effect of conventional tillage than no-tillage technology. From point of view of experimental years, the most statistically significant effect had year 2014, with wet vegetation season.
  
  KEY WORDS: soil tillage, soil water storage, heavy soils
  
  Address:
  - Dana Kotorová, NPPC – Agroecology Research Institute Michalovce, Špitálska 1273, 071 01 Michalovce, Slovak Republic (Corresponding author. Tel.: Fax.: Email: kotorova@minet.sk)
  - Ladislav Kováč, NPPC – Agroecology Research Institute Michalovce, Špitálska 1273, 071 01 Michalovce, Slovak Republic

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 76 - 79, doi:
Scientific Paper, English

Branislav Kandra, Dana Pavelková: Soil water regime balancing at the selected location of East Slovakian Lowland during the verification period

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• The individual members of the balance equation were calculated and evaluated, using the mathematical model GLOBAL, in the selected growing seasons 2004, 2005 and 2015. The analysis was based on the calculated daily values of infiltration, interception, water flow through the lower boundary of soil profile, evaporation, transpiration and precipitation. The aim was to quantify the above elements of the water regime in the selected soil profile of Milhostov and also evaluate the suitability of this model. Verification showed a high level of dependence between calculated and measured values, which means that the model GLOBAL is an appropriate tool for simulation and balancing of soil water regime in conditions of the selected locality.
  
  KEY WORDS: soil water regime, numerical simulation, soil water balancing, East Slovakian Lowland
  
  Address:
  - Branislav Kandra, Ústav hydrológie SAV Bratislava, Výskumná hydrologická základňa Michalovce, Hollého 42, Michalovce 071 01, Slovenská republika (Corresponding author. Tel.: Fax.: Email: kandra@uh.savba.sk)
  - Dana Pavelková, Ústav hydrológie SAV Bratislava, Výskumná hydrologická základňa Michalovce, Hollého 42, Michalovce 071 01, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 80 - 85, doi:
Scientific Paper, English

Andrej Tall, Dana Pavelková: Relationship between gravimetric and volumetric water content of soil in conditions of East Slovakian Lowland

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• The aim of this contribution was to study dependence between gravimetric and volumetric water content of soil which resulted into pedotransfer function. This function would facilitate the calculation of volumetric water content of soil based on more easily calculated gravimetric water content of soil. Regarding the samples, 325 undisturbed soil samples were taken from 15 different locations of East-Slovakian lowland. Further, the samples underwent grain-size analysis and 2 759 measurements of gravimetric and volumetric water contents of soil were performed. The dependence between gravimetric and volumetric water content of soil is linear in soils with low content of clay fraction. When clay content was increasing, the linearity of dependency was vanishing and it started to copy the curve. This fact was caused by the volume changes of soil emerging due to the presence of clay minerals in soil. Pedotransfer function was obtained in the form of eight polynomial functions of second degree for eight different intervals of clay fraction component (particles <0.002 mm). The degree of reliability of this function is confirmed by the value r2=0.9962 as well as the value of mean absolute error: 0.7890 %.
  
  KEY WORDS: volumetric water content of soil, gravimetric water content of soil, pedotransfer function, volume changes of soil
  
  Address:
  - Andrej Tall, Ústav hydrológie SAV Bratislava, Výskumná hydrologická základňa Michalovce, Hollého 42, Michalovce 071 01, Slovenská republika (Corresponding author. Tel.: Fax.: Email: tall@uh.savba.sk)
  - Dana Pavelková, Ústav hydrológie SAV Bratislava, Výskumná hydrologická základňa Michalovce, Hollého 42, Michalovce 071 01, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 86 - 90, doi:
Scientific Paper, English

Milan Gomboš, Helena Hlavatá: Analysis of rainless periods on Eastern Slovakian Lowland

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• Precipitation and evapotranspiration are basic compounds of hydrologic cycle. Precipitation are crucial natural source of water in the soil. Precipitation amount and temporal distribution of the rainfall is important for water refilling of the environment for balanced periods. Drying of soil profile occurs during long rainless periods. Meteorological drought and subsequently soil drought occurs in case of sufficiently long rainless period. Therefore it is necessary to know size and statistical characteristics of rainless periods (RLP). The aim of the contribution is to identify important rainless periods, quantify temporal lengths, probability characteristics and trends of RLP. Stated knowledge is necessary for research of water regime of the soils during the creation, duration and disappearance of soil drought.
  
  KEY WORDS: rainless periods, probability, trend
  
  Address:
  - Milan Gomboš, Ústav hydrológie SAV Bratislava, Výskumná hydrologická základňa Michalovce, Hollého 42, Michalovce 071 01, Slovenská republika (Corresponding author. Tel.: Fax.: Email: gombos@uh.savba.sk)
  - Helena Hlavatá, Slovenský hydrometeorologický ústav Košice, Ďumbierska 26, 041 17 Košice, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 91 - 97, doi:
Scientific Paper, Slovak

Justína Vitková, Jana Skalová, Miroslava Jarabicová: Scenarios of air temperature and precipitation totals using a CGCM 3.1 model at Zahorska Lowland vs. reality

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• In this paper, we decided to evaluate the real measurements of air temperature and precipitation total and simulated data obtained using the climate model CGCM 3.1 by emission scenarios SRES A2 and SRES B1. The results are from Zahorska lowland, which is located in the western part of Slovakia. Trend of air temperature during the period 1996 – 2014 is higher compared to the simulated data. The trend in longer scale of the years 1961 – 2100 is almost identical with the SRES A2 scenario. The precipitation total has in the period 1996 – 2014 increasing trend, similar to the SRES B1 scenario, but the annual precipitation total is lower than the assumed scenario. The trend balanced in longer scale of the years 1961 – 2100 and it is lower than scenario prognoses. Reversing verification of simulated data is important because of applicability in our conditions and also to verifying the simulated data in the future.
  
  KEY WORDS: climate change, mathematical modelling, climate scenario, CGCM 3.1 Model
  
  Address:
  - Justína Vitková, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: vitkova@uh.savba.sk)
  - Jana Skalová, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika
  - Miroslava Jarabicová, Katedra vodného hospodárstva krajiny, Stavebná fakulta Slovenskej technickej univerzity v Bratislave, Radlinského 11, 813 68 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 98 - 103, doi:
Scientific Paper, Slovak

Marek Rodný, Justína Vitková, Peter Šurda, Dušan Igaz, Ján Horák, Jana Domanová, Tomáš Borza: Biochar, compost and inorganic fertilizer influence on available water holding capacity and bulk density of sandy loam soil

 Full Text in PDF     56 DOWNLOADS

• Biochar, a relatively new material, could be considered as a means to sequester carbon while concurrently improving soil chemical and physical characteristics. A synergic amelioration effect could be anticipated once biochar is applied in a mixture with compost. As it was proven by the results of this study, application of the biochar/compost mixture has positive effects on the available water holding capacity and bulk density of the sandy loam soil. However, there was only limited evidence of the inorganic fertilizer influence on the hydrophysical properties under study. The results were obtained from the unique, long term field experiment and fully demonstrated importance of such kind of experiments while testing new amelioration practices focused on strengthening resilience of the degradated agro-ecosystems towards impact of the global climate change and intensive agricultural land use.
  
  KEY WORDS: biochar, compost, available water holding capacity, soil bulk density
  
  Address:
  - Marek Rodný, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: rodny@uh.savba.sk)
  - Justína Vitková, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika
  - Peter Šurda, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika
  - Dušan Igaz, Katedra biometeorológie a hydrológie, FZKI, Slovenská poľnohospodárska univerzita, Tulipánová 7, 949 76 Nitra, Slovenská republika
  - Ján Horák, Katedra biometeorológie a hydrológie, FZKI, Slovenská poľnohospodárska univerzita, Tulipánová 7, 949 76 Nitra, Slovenská republika
  - Jana Domanová, Katedra biometeorológie a hydrológie, FZKI, Slovenská poľnohospodárska univerzita, Tulipánová 7, 949 76 Nitra, Slovenská republika
  - Tomáš Borza, Katedra biometeorológie a hydrológie, FZKI, Slovenská poľnohospodárska univerzita, Tulipánová 7, 949 76 Nitra, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 104 - 111, doi:
Scientific Paper, Slovak

Katarína Brezianská, Hana Hlaváčiková: Analyse of volume change and soil physical properties of sandy-loam soil and biochar mixtures

 Full Text in PDF     49 DOWNLOADS

• This study evaluates the volume changes and changes in the physical characteristics of the sandy-loam soil, to which was added biochar as an ingredient for soil quality improvement. Under laboratory conditions were created disturbed samples of soil and biochar mixtures which were added to the soil in the rates corresponding to 40 t.ha-1 and 80 t.ha-1. Samples were measured for moisture retention curve points. Afterwards, selected basic physical properties of the soil were calculated and evaluated according to the Coefficient of Linear Extensibility (COLE), the shrinkage potential of pure soil and mixtures was determined.
  
  KEY WORDS: biochar, volume change, soil physical properties
  
  Address:
  - Katarína Brezianská, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: stehlova@uh.savba.sk)
  - Hana Hlaváčiková, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 112 - 119, doi:
Scientific Paper, Slovak

Anton Zvala, Tomáš Orfánus, Dagmar Stojkovová, Viliam Nagy: Hydraulic conductivity of forest floor soil layer

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• The paper deals with the influence of organic litter material on hydraulic conductivity of the top surface layer of the forest soils. The hydraulic conductivity is one of the most important characteristics of the soil used in mathematical description of hydraulic processes within soil. The organic matter in forest floor horizons is formed by dead plant litter material at different stages of decomposition and aggregation and significantly influences initiation processes of infiltration and runoff generation. The forest floor horizons usually have extremely high porosity, very low bulk density, peculiar texture and structure determined by the level of mechanical and biochemical decomposition. This paper contains results of field and laboratory measurements of the hydraulic conductivity of organic horizons estimated by Guelph permeameter, tension disk permeameter, single-ring method and the method of variable hydraulic gradient (falling head). The results point to the ambiguousness of interpretations of commonly used methods of hydraulic conductivity assessment without consideration of local soil-vegetation conditions.
  
  KEY WORDS: hydraulic conductivity, forest floor horizons, forest soil
  
  Address:
  - Anton Zvala, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika (Corresponding author. Tel.: Fax.: Email: zvala@uh.savba.sk)
  - Tomáš Orfánus, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika
  - Dagmar Stojkovová, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika
  - Viliam Nagy, Ústav hydrológie SAV, Dúbravská cesta č. 9, 841 04 Bratislava, Slovenská republika

Acta Hydrologica Slovaca, Vol. 18, No. 1, 2017, p. 120 - 131, doi:
Scientific Paper, Slovak

Zdeněk Kostka, Ladislav Holko: Application of electrical resistivity tomography at the monitoring of infiltration into soil profile

 Full Text in PDF     53 DOWNLOADS

• Determination of the share of water infiltrating into soil profile at subsurface runoff and at groundwater recharge is very important as well as ambitious mission of hydrology. Non-destructive monitoring of water movement paths in soil can be accomplished by applying of geophysical methods that are sensitive to differences of water and soil physical characteristics. The analysis of electrical resistivity tomography measurements after the application of irrigation on soil surface at horizontal and slope sites demonstrated the ability of this method to indicate water movement primarily in the start phase of infiltration before the dispersion of the front of infiltrating water. After that the sharp boundary between the environments with different physical characteristics, essential to the application of geophysical methods, cease to exist.
  
  KEY WORDS: infiltration, soil profile, hydrogeophysics, electrical resistivity tomography
  
  Address:
  - Zdeněk Kostka, Ústav hydrológie SAV, Experimentálna hydrologická základňa, Ondrašovská 16, 03105 Liptovský Mikuláš, Slovenská republika (Corresponding author. Tel.: Fax.: Email: kostka@uh.savba.sk)
  - Ladislav Holko, Ústav hydrológie SAV, Experimentálna hydrologická základňa, Ondrašovská 16, 03105 Liptovský Mikuláš, Slovenská republika