National Repository of Grey Literature 60 records found  beginprevious51 - 60  jump to record: Search took 0.00 seconds. 
The effect of soil structure on the hydraulic characteristics of the soil
Čermák, Petr ; Doležal, Petr (referee) ; Kameníčková, Ivana (advisor)
Soil is very important in the hydrological cycle of landscape. The retention and storage ability depends on the quality, type of structure and other properties of the soil. The retention ability of soil is determined by gravitational pores (the coarsest pores), which are drained off after filling the water. The accumulation depends on the capillary pores in which water is bounded by capillary forces. The soil works also as a filter´s environment which cleans naturally the water. This process can be also converse, when various substances are released from soil to water. The state and amount of water between the surface of soil and level of groundwater affect many important processes such as fertility of soil, drain from drainage area, supply of groundwater sources and others. Structure of soil changes fundamentally by cultivation of soil and types of farming crops. Aggregates are mechanical destructed by weather conditions and soil gradually loses its good qualities, fertility is reducing and flood protection is decreasing. This fact can be avoided by right choice of crops and the type of tillage soil.
Using program Rosetta to estimate of soil moisture retention curves from experimental size Bohaté Málkovice
Čermák, Petr ; Doležal, Petr (referee) ; Kameníčková, Ivana (advisor)
Hydraulic characteristics are the most important properties of soil, i.e. retention curve of soil moisture and hydraulic conductivity. Hydraulic conductivity of soil characterizes the ability of the soil to conduct water. Retention curve expresses the relationship between moisture and moisture potential of soil. The running of retention curve is influenced by many factors, eg. grain size and mineralogical composition, content of humus, reduce bulk density and structure of soil. Measurement of retention curves takes a lot of time and money in laboratory conditions therefore pedotransfer functions seem to be an alternative solution. The thesis aims to estimate moisture retention curves of soil in a selected area of interest in South Moravia using program Rosetta (Schaap, 2003). Data of granularity (% content of clay, sand and dust), bulk density of soil and hydrolimits field water capacity and wilting point were used as predictors in individual models of program Rosetta. Data of grain were matched by FAO / USDA system. Retention curves of soil moisture were measured on a sand tank and overpressure devices. The measured retention curves were parameterized by RETC program. Estimated retention curves were graphically compared with measured to determine the quality of the estimate. The accuracy of the estimate was assessed by correlation coefficient R of determination coefficient R2 and standard error SMRE. Usability own derivatives pedotransfer functions is hard to say due to the size of the input data file. I would recommend further verification of data at the other localities in south Moravia.
Pedotransfer functions for estimation of moisture retention curves of medium-heavy soils of South Moravia
Gavlasová, Iva ; Doležal, Petr (referee) ; Kameníčková, Ivana (advisor)
The most important characteristics of each soil is its hydro-physical properties, which include retention curve. Retention curve expresses the relationship between humidity and pressure head. It is course affected by many factors such as grain size and mineralogical composition, humus content, structure and bulk density of dry soil. This thesis deals with direct and indirect determination of one of the basic hydraulic characteristics of the soil, soil moisture retention curve. For laboratory determination of moisture retention curves were used for sand tank and pressure instruments. Measured body retention curves were optimized RETC program.For indirect determination of retention curves were used Pedotransfer function by Wösten et . al .(1998 ) , derived from the European soils and under HYPRES Šútora and Štekauerová (2000). As in the project Wösten et al . (1998), PTF were processed for arable land in the area. The accuracy of both models PTF was assessed by the correlation coefficient R and standard error RMSE. Simple models PTF provide estimates of retention curves with sufficient accuracy for practical use in the locality.
Determination of soil hydraulic characteristics in the selected location
Stoklásková, Adéla ; Doležal, Petr (referee) ; Kameníčková, Ivana (advisor)
This thesis deals with direct and indirect determination of soil hydraulic characteristics (retention curve and hydraulic conductivity) in the locality of Bohaté Málkovice. For laboratory determination of soil moisture retention curve is used sand tank and pressure relief device. For the indirect determination of soil hydraulic characteristics is used computer software Rosetta, which includes 5 models of pedotransfer functions. For estimatiton of retention curves are applied previously derived pedotransfer function (continuous parametric PTF and point PTF).
Analysis of the mutual relationship between two methods of field measurement of water infiltration into the soil
Larišová, Lucie ; Kriška,, Michal (referee) ; Kameníčková, Ivana (advisor)
This thesis deals with the theoretical description of the infiltration process and field measurements of infiltration in the cadastral territory of Bohaté Málkovice. The research work carried out in 2011 in an experimental area on Haplic Chernozem/FAO, medium-heavy loam soil. The experimental area was divided into two parts, the topsoil layer on these surfaces was processed by both classic and minimization technologies. The plots were sown by spring barley. The applied measurements of water infiltration into the soil were two-cylinder method and MiniDisc. Within the vicinity of the infiltration experiments with intact soil were collected samples for laboratory determination of saturated hydraulic conductivity. From the field measurements and laboratory experiments were determined values of hydraulic conductivity (saturated and unsaturated), and other infiltration characteristics, the cumulative infiltration and infiltration rate. To evaluate the infiltration of the heats was used three-paramether Philp type equation that provides a good estimate of saturated hydraulic conductivity. For the evaluation of the MiniDisc there was used the Zangova method that provides the unsaturated hydraulic conductivity. The laboratory evaluation of the saturated hydraulic conductivity was compared with the estimated values obtained from the field measurements. The values of the saturated hydraulic conductivity from the laboratory measurements are closely comparable with estimates obtained from the steady infiltration rates from the field experiments. The research results also showed that medium-heavy loam soil, when being processed by minimization including modification of the soil surface by digging, have a positive effect on the infiltration of water into the soil. This fact leads to a higher protection plants in the vegetative period and improvement of the retention and storage capacity of soil.
The project of the soil protection devices in the small watershed
Kravčenko, Matěj ; Kameníčková, Ivana (referee) ; Doležal, Petr (advisor)
The objective of this thesis is the project of the soil protection device in the small watershed. A municipality of Letonice in south-moravian county was analyzed for this purpose. This thesis contains the theory of soil erosion, theory of project of the soil protection and theoretical concepts for calculating the erosion washes using the Wischmeier-Smith (USLE) model. The area analysis was performed in GIS environment and it was based on a digital model of the terrain.
Quality farmland soils in the Czech Republic and in Europe - development, present and future
Drlíková, Barbora ; Doležal, Petr (referee) ; Kameníčková, Ivana (advisor)
Bachelor thesis documents the development of agricultural land in the Czech Republic and Europe. Further notes the current state of the quality of agricultural land on which adversely affect mainly the degradation processes. They are at work described in succession. The work also includes a kind of outlook regarding the development of soil quality. With so closely related to the legislative provisions dealing with the protection of soil in the Czech Republic and EU.
Changes in physical properties of the subsurface soil layers depending on the technology tillage
Bažantová, Adéla ; Larišová, Lucie (referee) ; Kameníčková, Ivana (advisor)
For the correct course of soil processes, plant growth and development is necessary the tillage of soil. Usually we choose between two technologies, that those adjustments are cariied out by. Both are conventional tillage, which uses plowing and minimization tillage, wherein is excluded plowing. Objective of this work is to determine the impact of these tillage treatments on selected physical properties of soil, i. e reduced bulk density of the soil, porosity, momentary contents of water and air in the soil. Soil samples were collected by Kopecky rollers (V = 100 cm3) taken from depths of 0,1; 0,2 and 0,3 m that were used to evaluate. Two samples were collected each July. This period is referred as a critical due to higher soil compaction (movement of mechanization, root system of plants and rainfall totals). Experimental research was conducted in years 2008 – 2011 in the village Bohaté Málkovice.
The design of erosion control measures in a small basin
Prchlíková, Simona ; Kameníčková, Ivana (referee) ; Doležal, Petr (advisor)
Main goal of this bachelor thesis was the proposal for protection against erosion in selected river basin. Digital model of terrain was created with the help of ArcGis tools. Average yearly erosion wash off was determined by calculation in ArcGis software. The assessment was determined by two factors that influence threat level for particular area. The goal is to highlight the differences between the levels of threat by water erosion after two various rain types. Selected erosion control measures were suggested for the worse option. Chosen appropriate measures were as follows: grassing, erosion control crop rotation and interruption of slope by furrow. Subsequently, new erosion control measures were implemented into the calculation of new state of threatened area. In the final comparison, after implementing erosion control measures, it was a significant and noticeable improvement in conditions. Solution respects trend of water retention in the landscape and use of low-cost measures.
The soil protection in Czech republic and European Union
Gavlasová, Iva ; Marton, Daniel (referee) ; Kameníčková, Ivana (advisor)
Bachelor's work affects and documents the basic degradation processes in the soil, agricultural and forest, which belongs to the natural wealth of our country. Further points to the legislative provisions relating to the protection of the soil in the Czech Republic and the EU and their effectiveness. Gradually are analyzed the various degradation processes, erosion, soil compaction, a land grab, desertification, salinisation and sodifikace soils, soil contamination.

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