Evapotranspiration is one of the key elements of water balance in nature. It significantly influe... more Evapotranspiration is one of the key elements of water balance in nature. It significantly influences the water supply in the unsaturated zone of a soil profile. The unsaturated zone is a water source for the biosphere. The aim of this study is to measure, calculate and analyze the course of actual evapotranspiration, precipitation and dew totals as well as the totals of water flows at the lower boundary of unsaturated zone and the change in water content in specified soil volume. The measurements are used for verifying the results of numerical simulation. The methods used in the study were chosen based on the hypothesis that dynamics of water supply changes in the unsaturated zone is the result of the interactions between atmosphere, soil and plant cover. The elements of water balance were quantified by the methods of water balance, lysimeter measurements and numerical simulation on the model HYDRUS-1D, version 4. The abovementioned parameters were quantified for the East Slovakian...
The results of authors of submitted article are based on knowledge that soil retention capacity a... more The results of authors of submitted article are based on knowledge that soil retention capacity and soil water availability for plants is different in various soil types. Soil types are defined by texture. It is expected that different retention capacity of soil and different availability of soil water for plants is reflected in changes of moisture regime in space and time. Moisture regime monitoring results captures these changes. Changes can be statistically and graphically analysed and interpreted. The results gained from three localities of East Slovakian Lowland (ESL) of the year 2015 extreme drought period were selected for presentation. Examined localities differs by texture compound. Localities are representing the heaviest clay soils, lighter clay-loam-silty soils and the lightest loam soils. Soil volume humidity was monitored into the depth of 1.00 m by layers of 0.10 m. All samples were taken in the same day in examined localities. Descriptive statistics method was used for data processing. Graphical representation is processed in form of chronoizophlets, line and column graphs. Different monitoring results of volume moisture and water storage in different soil types are quantified in the article. Winter water refill of soil profile, soil water storage, vertical scatter of soil profile moisture volume, temporal and spatial moisture regime changes and availability of soil water for plant cover was analysed within this quantification. The results of analysis and interpretation of moisture regime in different soil environments are necessary for water management of the country and for the design of adaptive measures for the periods of soil drought.
Short abstracts in EnglishAvailable from Slovak Centre of Scientific and Technical Information, u... more Short abstracts in EnglishAvailable from Slovak Centre of Scientific and Technical Information, under shelf-number: A583306 / Slovenska Technicka Univerzita v BratislaveSIGLESKSlovak Republi
In hydropedological research and in various scientific experiments, the determination of the sett... more In hydropedological research and in various scientific experiments, the determination of the settling rate of soil microparticles is a frequent task. Many laboratory procedures for measuring sedimentation rate are based on the Stokes equation. In recent years, methods based on the principle of laser diffraction can be used to measure grain-size distribution and deposition rate of microparticles. The output of the measurements by a laser diffraction method is statistical distribution of soil texture in the measured sample by particle size expressed in % of volume. Measurements were performed in a wet way by MALVERN Instruments device called Mastersizer 2000. The proposed method is based on measuring the time required for soil particles of certain diameter to pass certan distance. The size of soil microparticles present in space and time is defined by probability. Probability is defined in the form of a grain size distribution function. The advantage of the proposed method is its robustness and elimination of human factor errors. This paper presents the results of theoretical approaches and experimental measurements of the settling rate of soil microparticles. Soil samples were taken in the East Slovakian Lowland. Measurements are performed for the selected sizes of soil microparticles for a probability of occurrence of 90%, i.e for d(90). The results are compared with the results calculated by the Stokes equation.
Advances in Thermal Processes and Energy Transformation
In general, soil is defined as a top, weathered layer of the Earth crust, which is suitable for p... more In general, soil is defined as a top, weathered layer of the Earth crust, which is suitable for plant growth. In the system soil - plants – atmosphere, mass and energy is transformed into biomass. This transformation is enabled by photosynthesis and photosynthesis occurs only if there is a water flow between soil, plants and atmosphere. The process of water transfer from soil, through soil surface and plant cover is called evapotranspiration. Among the most important elements of the hydrological cycle are rainfall and water evaporation. The contribution aims at quantifying the role of evaporation during the process of soil profile drying. This contribution examines the impact of evaporation deficiency, which is the difference between potential and actual evapotranspiration, on the drying of a soil profile. Drying process is quantified by analysing the changes of soil water storage with regard to the point of decreased availability. The analysis was based on the numerical experiment ...
Soil volume changes of heavy soils due to soil water content change are followed by their volume ... more Soil volume changes of heavy soils due to soil water content change are followed by their volume changes in the process of its shrinkage and swelling. Values of soil volume changes depend on the type and on the content of clay minerals and on soil water content as well. Content of clay minerals is usually stable at the site, but soil water content is changing, depending on meteorological and hydrological conditions. Soil volume changes are performing in both – horizontal and vertical directions. Horizontal deformation of soil creates soil cracks and changes of their dimensions, vertical deformations lead to soil surface level changes. At a given time soil water content W depends on the thickness of the vadose zone layer Δz of soil, i.e. ΔW = F (Δz). The article presents results of integral soil water content calculation based on the above mentioned relationship. Vertical changes of soil surface level were measured in the field, near the site Senne (East Slovakia Lowland).
IOP Conference Series: Earth and Environmental Science, 2017
This work analyses the problem of measuring water retention curves in heavy soils. The results pr... more This work analyses the problem of measuring water retention curves in heavy soils. The results present the differences between soil water retention curves measured in soil samples collected from the selected localities of the Czech and Slovak area. In the drying process, the results showed an increased rate of soil shrinkage depending on clay content and water content. The rate of shrinkage affected the results of the water retention curves points measurement.
The lower boundary of unsaturated soil zone is formed by groundwater level. At this level, water ... more The lower boundary of unsaturated soil zone is formed by groundwater level. At this level, water from unsaturated soil zone flows to groundwater and vice versa. Groundwater penetrates the unsaturated zone. By capillary rise, groundwater can supply water storage in the root zone and thus influence on actual evaporation in this soil layer. The degree to which this occurs depends on the given soil texture and the groundwater level position with regard to the position of lower root zone boundary.
The Czech Republic (CR) lies on the watershed divide of three seas—The North, Baltic and Black Se... more The Czech Republic (CR) lies on the watershed divide of three seas—The North, Baltic and Black Seas. The watershed of these seas divides the territory of the CR into three international catchment areas (Labe, Odra and Danube). In conjunction with the fulfilment of obligations arising from the Convention of the European Economic Commission of the United Nations Organisation on the protection and use of transboundary watercourses and international lakes, an “International Commission” was founded in 1990–1998 for each international catchment area. The CR is a member of the International Commissions for the protection of these catchment areas. The purpose of the activity of these institutions is to support cooperation in water management at the level of international catchment areas. It is obvious that practically all significant watercourses in the CR drain water beyond its boundary on the territories of the neighbouring states, resulting in the fact that water sources in the CR are practically dependent on the amount and distribution of atmospheric precipitation. In the context of discussing changing climatic conditions, atmospheric precipitation of very different intensities increases the likelihood of the occurrence of extreme floods and dry episodes. The theme of protection from the consequences of floods and drought is part of joint debates of all three international commissions. The approach to the solution of the issues above, however, can be different because it is based on the current conditions of the given international catchment area. Many fields and areas give attention to the theme of threats posed by natural disasters created by flood situations and drought not only from the view of science. It is not possible to prevent floods or drought by the present scientific knowledge and technical options. In case of floods, it is possible to reduce their impact on the lives and property of inhabitants by constructing efficient flood control works. However, it is necessary to have in mind that even the best flood control measure will only be as reliable, efficient and safe as its weakest element will be reliable, efficient and safe. In many cases, this element is earth-fill dams. Therefore, it is necessary to have continuous and long-term information on their condition. When addressing the issue of drought in the CR, it is necessary to realise that the absolute majority of water sources depends on the retention and accumulation of water in the territory of the CR. At present, the impacts of drought and lack of water in the conditions of the CR are significantly mitigated by the existing water management infrastructure. However, it can be expected for the future that the existing water sources will not be sufficient. Not only the aspect of the potentially diminishing available amount of surface water and subsurface water in the CR will be problematic, but also the aspect of the unsuitable quality of water. Also from this aspect, it is possible to see the earth-fill dam as an element that helps retain and accumulate water in the landscape. The reality is that every inhabitant of the CR is a significant user of its water sources, and it is necessary to bear the responsibility for them. Unfortunately, people usually realise neither the significance nor the value of the discussed irreplaceable nature wealth for everyday life, nor the scope of activities and financial costs that are associated with this “matter of course”. In this chapter, the team of the authors provides a view of international cooperation and its achievements when dealing with a project of applied research in the EUREKA programme, which was focused on the development and construction of monitoring technology enabling changes in water content to be monitored in a porous medium. The selected results are documented in a link to remedial measures applied to earth-fill dams of water reservoirs in the conditions of the CR, emphasising the use of the method of electrical impedance spectrometry. The authors are aware of the fact that it is only a fragment of the solution of the complex of the outlined issue. However, it is obvious that without the safe operation of water management works, the irreplaceable part of which is their monitoring, it is impossible neither to ensure water sources nor to manage them.
Challenging Issues on Environment and Earth Science Vol. 6, 2021
Clay minerals can absorb water and incorporate it into its microstructure. During these processes... more Clay minerals can absorb water and incorporate it into its microstructure. During these processes (water absorption or loss), volume changes occur in clay particles. High content of clay particles in soils can lead to their volume changes, provided there are simultaneous changes in moisture. Volume changes of heavy soils occuring during shrinking and swelling processes are important because they are accompanied with soil surface shrinkage and cracks formation. Formation and dynamics of cracks have an important impact on transport processes in heavy soils and consequently on their water regime. The presented chapter describes the results of the analysis of the influence of clay content on the coefficient of linear extensibility (COLE), potential of linear extensibility (PLE) and geometric factor of soils. The hypothesis about the influence of texture on the value of the volume change potential and the geometric factor, and thus on the degree of distribution of volume changes on the vertical and horizontal components, was verified. The hypothesis assumes that the clay soil component has the greatest influence on the potential of volume changes and on the geometric factor value. New information is obtained on the basis of field and laboratory measurements. Results will be used as inputs for numerical simulation of water regimes of heavy soils.
IOP Conference Series: Earth and Environmental Science, 2017
The volume changes in the soils are manifested both by the formation of cracks and by the vertica... more The volume changes in the soils are manifested both by the formation of cracks and by the vertical movement of the soil surface. Both of these could be generally negative for engineering constructions. The Coefficient of Linear Extensibility (COLE) is used to quantify volume changes. In this work a pedotransfer function was designed to calculate the COLE potential. Calculation is based on the texture of the soil. This function was designed on the basis of 169 samples of soil samples taken at 11 locations in the East Slovak lowland.
IOP Conference Series: Earth and Environmental Science, Oct 1, 2017
One of the basic characteristics of heavy soils is their capacity to change their volume in horiz... more One of the basic characteristics of heavy soils is their capacity to change their volume in horizontal plane they are represented by formation of cracks and in vertical plane by vertical movement of soil surface. Non-dimensional geometric factor rs is the ratio of participation in soil volumetric changes of both crack formation and vertical movements. In theory, rs can acquire values in the interval: rs ∈ 〈1, ∞〉.
During simulation of a water regime of heavy soils, it is necessary to know the isotropy paramete... more During simulation of a water regime of heavy soils, it is necessary to know the isotropy parameters of any volume changes. Volume changes appear in both vertical and horizontal directions. In vertical directions, they appear as a topsoil movement, and in horizontal directions as the formation of a crack network. The ratio between horizontal and vertical change is described using the geometric factor, rs. In the present paper, the distribution of volume changes to horizontal and vertical components is characterized by the geometric factor, in selected soil profiles, in the East Slovakian Lowland. In this work the effect of soil texture on the value of the geometric factor and thus, on the distribution of volume changes to vertical and horizontal components was studied. Within the hypothesis, the greatest influence of the clay soil component was shown by the geometric factor value. New information is obtained on the basis of field and laboratory measurements. Results will be used as i...
Rainfall and evaporation belong to the basic components of the hydrological cycle. Rainfalls are ... more Rainfall and evaporation belong to the basic components of the hydrological cycle. Rainfalls are a decisive natural source of water in the soil. For water replenishment in the natural environment, it is important not only the sum of the rainfall for the balanced period but also the time distribution. In the case of long non-rainfall periods, the soil profile is dried. In the sufficiently long non-rainfall period, the water reserves in the unsaturated zone of the soil profile change and the actual evapotranspiration is reduced. There is a meteorological and then dry soil formation. For the design of adaptation measures, it is necessary to quantify the mentioned hydrological processes. These were investigated in the central area of the Eastern Slovak Lowland between 1970 and 2015. Significant non-rainfall periods, their periodicity and statistical characteristics have been identified. In the course of significant non-rainfall intervals during the vegetation periods the water reserves in the root layer of the soil were analysed up to a depth of 1 m, the actual and potential evapotranspiration, the evapotranspiration deficit, the groundwater level and the air temperature. The longest non-rainfall periods exceeded 30 days.
Volume changes of soil associated with soil moisture changes are caused by the presence of clay m... more Volume changes of soil associated with soil moisture changes are caused by the presence of clay minerals from illite and montmorillonite groups. Clay minerals are found in the so-called clay soil component which can be quantified by laboratory analysis of the soil particle-size distribution. Consequently, the potential for volume changes in soil can be assessed from soil texture. In our study, 172 soil samples with different textures were used to measure dependencies between volume changes in soil and changes in soil moisture under laboratory conditions. The samples were collected from 11 sites in the Eastern Slovak Lowland. On the basis of the measurements, 10 mathematical models were created to compute the correlation between volume changes of soil and soil moisture content and texture. The highest accuracy was obtained with the model which assumes the content of particles < 0.002 mm. When comparing the clay particles < 0.001 mm (colloidal clay) with the particles < 0.002...
The aim of the submitted paper is to identify the lower limit of Stokes' law for calculating the ... more The aim of the submitted paper is to identify the lower limit of Stokes' law for calculating the deposition rate of soil microparticles. The authors' hypothesis on the lower limit of Stokes' law is based on the idea that with the gradual formation of the colloidal dispersion system, both the particle size and the sedimentation rate decrease. It is assumed that under the lower particle size limit, Stokes' law does not apply. As a result of the diffusion, the state of the sedimentation equilibrium gradually emerges. The results of the experiment showed that in laboratory conditions, Stokes' equation ceases to be valid for sedimentation of the particles sized d(90) < 2 μm. During the experiment, a dynamic sedimentation equilibrium was reached at the particle size d(90) = 0.27 μm. The scientific contribution of this knowledge is the accuracy of the determination of hydropedological characteristics dependent on the texture of the soil. In this context, the results stated in the paper define the lower limit of the validity for the laboratory procedures determining soil texture on the basis of the sedimentation methods. To identify the textures below this limit, it is necessary to choose the methods based on other principles. Determination of the lower limit is particularly important in clay soils containing a high proportion of clay particles (clay particles < 2 μm).
... The aim of presented report is to quantify one of the stress factors on the example of chosen... more ... The aim of presented report is to quantify one of the stress factors on the example of chosen soil profile. In other words we want to quantify water drought by the volume of soil cracks (oltész, 2007; Nagy et al., 2007; tekauerová-útor, 2008). ... tekauerová, V. - útor, J.: 2008. ...
During the vegetation season, the water storage in the soil aeration zone is influenced by meteor... more During the vegetation season, the water storage in the soil aeration zone is influenced by meteorological phenomena and by the vegetated cover. If the groundwater table is in contact with the soil profile, its contribution to water storage must be considered. This impact can be either monitored directly or the mathematical model of the soil moisture regime can be used to simulate it. We present the results of monitoring soil water content in the aeration zone of the East Slovakian Lowland. The main problem is the evaluation of the soil water storage in seasons and in years in the soil profile. Until now, classification systems of the soil water regime evaluation have been mainly based upon climatological factors and soil morphology where the classification has been realized on the basis of indirect indicators. Here, a new classification system based upon quantified data sets is introduced and applied for the measured data. The system considers the degree of accessibility of soil wat...
Evapotranspiration is one of the key elements of water balance in nature. It significantly influe... more Evapotranspiration is one of the key elements of water balance in nature. It significantly influences the water supply in the unsaturated zone of a soil profile. The unsaturated zone is a water source for the biosphere. The aim of this study is to measure, calculate and analyze the course of actual evapotranspiration, precipitation and dew totals as well as the totals of water flows at the lower boundary of unsaturated zone and the change in water content in specified soil volume. The measurements are used for verifying the results of numerical simulation. The methods used in the study were chosen based on the hypothesis that dynamics of water supply changes in the unsaturated zone is the result of the interactions between atmosphere, soil and plant cover. The elements of water balance were quantified by the methods of water balance, lysimeter measurements and numerical simulation on the model HYDRUS-1D, version 4. The abovementioned parameters were quantified for the East Slovakian...
The results of authors of submitted article are based on knowledge that soil retention capacity a... more The results of authors of submitted article are based on knowledge that soil retention capacity and soil water availability for plants is different in various soil types. Soil types are defined by texture. It is expected that different retention capacity of soil and different availability of soil water for plants is reflected in changes of moisture regime in space and time. Moisture regime monitoring results captures these changes. Changes can be statistically and graphically analysed and interpreted. The results gained from three localities of East Slovakian Lowland (ESL) of the year 2015 extreme drought period were selected for presentation. Examined localities differs by texture compound. Localities are representing the heaviest clay soils, lighter clay-loam-silty soils and the lightest loam soils. Soil volume humidity was monitored into the depth of 1.00 m by layers of 0.10 m. All samples were taken in the same day in examined localities. Descriptive statistics method was used for data processing. Graphical representation is processed in form of chronoizophlets, line and column graphs. Different monitoring results of volume moisture and water storage in different soil types are quantified in the article. Winter water refill of soil profile, soil water storage, vertical scatter of soil profile moisture volume, temporal and spatial moisture regime changes and availability of soil water for plant cover was analysed within this quantification. The results of analysis and interpretation of moisture regime in different soil environments are necessary for water management of the country and for the design of adaptive measures for the periods of soil drought.
Short abstracts in EnglishAvailable from Slovak Centre of Scientific and Technical Information, u... more Short abstracts in EnglishAvailable from Slovak Centre of Scientific and Technical Information, under shelf-number: A583306 / Slovenska Technicka Univerzita v BratislaveSIGLESKSlovak Republi
In hydropedological research and in various scientific experiments, the determination of the sett... more In hydropedological research and in various scientific experiments, the determination of the settling rate of soil microparticles is a frequent task. Many laboratory procedures for measuring sedimentation rate are based on the Stokes equation. In recent years, methods based on the principle of laser diffraction can be used to measure grain-size distribution and deposition rate of microparticles. The output of the measurements by a laser diffraction method is statistical distribution of soil texture in the measured sample by particle size expressed in % of volume. Measurements were performed in a wet way by MALVERN Instruments device called Mastersizer 2000. The proposed method is based on measuring the time required for soil particles of certain diameter to pass certan distance. The size of soil microparticles present in space and time is defined by probability. Probability is defined in the form of a grain size distribution function. The advantage of the proposed method is its robustness and elimination of human factor errors. This paper presents the results of theoretical approaches and experimental measurements of the settling rate of soil microparticles. Soil samples were taken in the East Slovakian Lowland. Measurements are performed for the selected sizes of soil microparticles for a probability of occurrence of 90%, i.e for d(90). The results are compared with the results calculated by the Stokes equation.
Advances in Thermal Processes and Energy Transformation
In general, soil is defined as a top, weathered layer of the Earth crust, which is suitable for p... more In general, soil is defined as a top, weathered layer of the Earth crust, which is suitable for plant growth. In the system soil - plants – atmosphere, mass and energy is transformed into biomass. This transformation is enabled by photosynthesis and photosynthesis occurs only if there is a water flow between soil, plants and atmosphere. The process of water transfer from soil, through soil surface and plant cover is called evapotranspiration. Among the most important elements of the hydrological cycle are rainfall and water evaporation. The contribution aims at quantifying the role of evaporation during the process of soil profile drying. This contribution examines the impact of evaporation deficiency, which is the difference between potential and actual evapotranspiration, on the drying of a soil profile. Drying process is quantified by analysing the changes of soil water storage with regard to the point of decreased availability. The analysis was based on the numerical experiment ...
Soil volume changes of heavy soils due to soil water content change are followed by their volume ... more Soil volume changes of heavy soils due to soil water content change are followed by their volume changes in the process of its shrinkage and swelling. Values of soil volume changes depend on the type and on the content of clay minerals and on soil water content as well. Content of clay minerals is usually stable at the site, but soil water content is changing, depending on meteorological and hydrological conditions. Soil volume changes are performing in both – horizontal and vertical directions. Horizontal deformation of soil creates soil cracks and changes of their dimensions, vertical deformations lead to soil surface level changes. At a given time soil water content W depends on the thickness of the vadose zone layer Δz of soil, i.e. ΔW = F (Δz). The article presents results of integral soil water content calculation based on the above mentioned relationship. Vertical changes of soil surface level were measured in the field, near the site Senne (East Slovakia Lowland).
IOP Conference Series: Earth and Environmental Science, 2017
This work analyses the problem of measuring water retention curves in heavy soils. The results pr... more This work analyses the problem of measuring water retention curves in heavy soils. The results present the differences between soil water retention curves measured in soil samples collected from the selected localities of the Czech and Slovak area. In the drying process, the results showed an increased rate of soil shrinkage depending on clay content and water content. The rate of shrinkage affected the results of the water retention curves points measurement.
The lower boundary of unsaturated soil zone is formed by groundwater level. At this level, water ... more The lower boundary of unsaturated soil zone is formed by groundwater level. At this level, water from unsaturated soil zone flows to groundwater and vice versa. Groundwater penetrates the unsaturated zone. By capillary rise, groundwater can supply water storage in the root zone and thus influence on actual evaporation in this soil layer. The degree to which this occurs depends on the given soil texture and the groundwater level position with regard to the position of lower root zone boundary.
The Czech Republic (CR) lies on the watershed divide of three seas—The North, Baltic and Black Se... more The Czech Republic (CR) lies on the watershed divide of three seas—The North, Baltic and Black Seas. The watershed of these seas divides the territory of the CR into three international catchment areas (Labe, Odra and Danube). In conjunction with the fulfilment of obligations arising from the Convention of the European Economic Commission of the United Nations Organisation on the protection and use of transboundary watercourses and international lakes, an “International Commission” was founded in 1990–1998 for each international catchment area. The CR is a member of the International Commissions for the protection of these catchment areas. The purpose of the activity of these institutions is to support cooperation in water management at the level of international catchment areas. It is obvious that practically all significant watercourses in the CR drain water beyond its boundary on the territories of the neighbouring states, resulting in the fact that water sources in the CR are practically dependent on the amount and distribution of atmospheric precipitation. In the context of discussing changing climatic conditions, atmospheric precipitation of very different intensities increases the likelihood of the occurrence of extreme floods and dry episodes. The theme of protection from the consequences of floods and drought is part of joint debates of all three international commissions. The approach to the solution of the issues above, however, can be different because it is based on the current conditions of the given international catchment area. Many fields and areas give attention to the theme of threats posed by natural disasters created by flood situations and drought not only from the view of science. It is not possible to prevent floods or drought by the present scientific knowledge and technical options. In case of floods, it is possible to reduce their impact on the lives and property of inhabitants by constructing efficient flood control works. However, it is necessary to have in mind that even the best flood control measure will only be as reliable, efficient and safe as its weakest element will be reliable, efficient and safe. In many cases, this element is earth-fill dams. Therefore, it is necessary to have continuous and long-term information on their condition. When addressing the issue of drought in the CR, it is necessary to realise that the absolute majority of water sources depends on the retention and accumulation of water in the territory of the CR. At present, the impacts of drought and lack of water in the conditions of the CR are significantly mitigated by the existing water management infrastructure. However, it can be expected for the future that the existing water sources will not be sufficient. Not only the aspect of the potentially diminishing available amount of surface water and subsurface water in the CR will be problematic, but also the aspect of the unsuitable quality of water. Also from this aspect, it is possible to see the earth-fill dam as an element that helps retain and accumulate water in the landscape. The reality is that every inhabitant of the CR is a significant user of its water sources, and it is necessary to bear the responsibility for them. Unfortunately, people usually realise neither the significance nor the value of the discussed irreplaceable nature wealth for everyday life, nor the scope of activities and financial costs that are associated with this “matter of course”. In this chapter, the team of the authors provides a view of international cooperation and its achievements when dealing with a project of applied research in the EUREKA programme, which was focused on the development and construction of monitoring technology enabling changes in water content to be monitored in a porous medium. The selected results are documented in a link to remedial measures applied to earth-fill dams of water reservoirs in the conditions of the CR, emphasising the use of the method of electrical impedance spectrometry. The authors are aware of the fact that it is only a fragment of the solution of the complex of the outlined issue. However, it is obvious that without the safe operation of water management works, the irreplaceable part of which is their monitoring, it is impossible neither to ensure water sources nor to manage them.
Challenging Issues on Environment and Earth Science Vol. 6, 2021
Clay minerals can absorb water and incorporate it into its microstructure. During these processes... more Clay minerals can absorb water and incorporate it into its microstructure. During these processes (water absorption or loss), volume changes occur in clay particles. High content of clay particles in soils can lead to their volume changes, provided there are simultaneous changes in moisture. Volume changes of heavy soils occuring during shrinking and swelling processes are important because they are accompanied with soil surface shrinkage and cracks formation. Formation and dynamics of cracks have an important impact on transport processes in heavy soils and consequently on their water regime. The presented chapter describes the results of the analysis of the influence of clay content on the coefficient of linear extensibility (COLE), potential of linear extensibility (PLE) and geometric factor of soils. The hypothesis about the influence of texture on the value of the volume change potential and the geometric factor, and thus on the degree of distribution of volume changes on the vertical and horizontal components, was verified. The hypothesis assumes that the clay soil component has the greatest influence on the potential of volume changes and on the geometric factor value. New information is obtained on the basis of field and laboratory measurements. Results will be used as inputs for numerical simulation of water regimes of heavy soils.
IOP Conference Series: Earth and Environmental Science, 2017
The volume changes in the soils are manifested both by the formation of cracks and by the vertica... more The volume changes in the soils are manifested both by the formation of cracks and by the vertical movement of the soil surface. Both of these could be generally negative for engineering constructions. The Coefficient of Linear Extensibility (COLE) is used to quantify volume changes. In this work a pedotransfer function was designed to calculate the COLE potential. Calculation is based on the texture of the soil. This function was designed on the basis of 169 samples of soil samples taken at 11 locations in the East Slovak lowland.
IOP Conference Series: Earth and Environmental Science, Oct 1, 2017
One of the basic characteristics of heavy soils is their capacity to change their volume in horiz... more One of the basic characteristics of heavy soils is their capacity to change their volume in horizontal plane they are represented by formation of cracks and in vertical plane by vertical movement of soil surface. Non-dimensional geometric factor rs is the ratio of participation in soil volumetric changes of both crack formation and vertical movements. In theory, rs can acquire values in the interval: rs ∈ 〈1, ∞〉.
During simulation of a water regime of heavy soils, it is necessary to know the isotropy paramete... more During simulation of a water regime of heavy soils, it is necessary to know the isotropy parameters of any volume changes. Volume changes appear in both vertical and horizontal directions. In vertical directions, they appear as a topsoil movement, and in horizontal directions as the formation of a crack network. The ratio between horizontal and vertical change is described using the geometric factor, rs. In the present paper, the distribution of volume changes to horizontal and vertical components is characterized by the geometric factor, in selected soil profiles, in the East Slovakian Lowland. In this work the effect of soil texture on the value of the geometric factor and thus, on the distribution of volume changes to vertical and horizontal components was studied. Within the hypothesis, the greatest influence of the clay soil component was shown by the geometric factor value. New information is obtained on the basis of field and laboratory measurements. Results will be used as i...
Rainfall and evaporation belong to the basic components of the hydrological cycle. Rainfalls are ... more Rainfall and evaporation belong to the basic components of the hydrological cycle. Rainfalls are a decisive natural source of water in the soil. For water replenishment in the natural environment, it is important not only the sum of the rainfall for the balanced period but also the time distribution. In the case of long non-rainfall periods, the soil profile is dried. In the sufficiently long non-rainfall period, the water reserves in the unsaturated zone of the soil profile change and the actual evapotranspiration is reduced. There is a meteorological and then dry soil formation. For the design of adaptation measures, it is necessary to quantify the mentioned hydrological processes. These were investigated in the central area of the Eastern Slovak Lowland between 1970 and 2015. Significant non-rainfall periods, their periodicity and statistical characteristics have been identified. In the course of significant non-rainfall intervals during the vegetation periods the water reserves in the root layer of the soil were analysed up to a depth of 1 m, the actual and potential evapotranspiration, the evapotranspiration deficit, the groundwater level and the air temperature. The longest non-rainfall periods exceeded 30 days.
Volume changes of soil associated with soil moisture changes are caused by the presence of clay m... more Volume changes of soil associated with soil moisture changes are caused by the presence of clay minerals from illite and montmorillonite groups. Clay minerals are found in the so-called clay soil component which can be quantified by laboratory analysis of the soil particle-size distribution. Consequently, the potential for volume changes in soil can be assessed from soil texture. In our study, 172 soil samples with different textures were used to measure dependencies between volume changes in soil and changes in soil moisture under laboratory conditions. The samples were collected from 11 sites in the Eastern Slovak Lowland. On the basis of the measurements, 10 mathematical models were created to compute the correlation between volume changes of soil and soil moisture content and texture. The highest accuracy was obtained with the model which assumes the content of particles < 0.002 mm. When comparing the clay particles < 0.001 mm (colloidal clay) with the particles < 0.002...
The aim of the submitted paper is to identify the lower limit of Stokes' law for calculating the ... more The aim of the submitted paper is to identify the lower limit of Stokes' law for calculating the deposition rate of soil microparticles. The authors' hypothesis on the lower limit of Stokes' law is based on the idea that with the gradual formation of the colloidal dispersion system, both the particle size and the sedimentation rate decrease. It is assumed that under the lower particle size limit, Stokes' law does not apply. As a result of the diffusion, the state of the sedimentation equilibrium gradually emerges. The results of the experiment showed that in laboratory conditions, Stokes' equation ceases to be valid for sedimentation of the particles sized d(90) < 2 μm. During the experiment, a dynamic sedimentation equilibrium was reached at the particle size d(90) = 0.27 μm. The scientific contribution of this knowledge is the accuracy of the determination of hydropedological characteristics dependent on the texture of the soil. In this context, the results stated in the paper define the lower limit of the validity for the laboratory procedures determining soil texture on the basis of the sedimentation methods. To identify the textures below this limit, it is necessary to choose the methods based on other principles. Determination of the lower limit is particularly important in clay soils containing a high proportion of clay particles (clay particles < 2 μm).
... The aim of presented report is to quantify one of the stress factors on the example of chosen... more ... The aim of presented report is to quantify one of the stress factors on the example of chosen soil profile. In other words we want to quantify water drought by the volume of soil cracks (oltész, 2007; Nagy et al., 2007; tekauerová-útor, 2008). ... tekauerová, V. - útor, J.: 2008. ...
During the vegetation season, the water storage in the soil aeration zone is influenced by meteor... more During the vegetation season, the water storage in the soil aeration zone is influenced by meteorological phenomena and by the vegetated cover. If the groundwater table is in contact with the soil profile, its contribution to water storage must be considered. This impact can be either monitored directly or the mathematical model of the soil moisture regime can be used to simulate it. We present the results of monitoring soil water content in the aeration zone of the East Slovakian Lowland. The main problem is the evaluation of the soil water storage in seasons and in years in the soil profile. Until now, classification systems of the soil water regime evaluation have been mainly based upon climatological factors and soil morphology where the classification has been realized on the basis of indirect indicators. Here, a new classification system based upon quantified data sets is introduced and applied for the measured data. The system considers the degree of accessibility of soil wat...
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Papers by Milan gomboš