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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Stanovení ztráty půdy erozí a návrh protierozních opatření

Psotová, Petra January 2018 (has links)
In this diploma thesis I dealt with the water erosion of soil in the area of Libotovský potok. The basin was divided into eight erosively enclosed units. I have counted the average long-term loss of land without anti-erosive measures and with anti-erosive measures as well as the transportation of floodplains for both of these situations. The aim of this work was to evaluate the severity of water erosion and to propose anti-erosion measures by using the universal equation (USLE) and modified equations (MUSLE). According to the results of the universal equation, it was clear that there was a very strong erosion in the river basin. The total loss of the land was 12 419.88 tones per year. Therefore, both organisational (leaving post-harvest remnants) and agro-technical measures (curb contouring) were proposed there in order to reduce the values of Factors C and P. After that, the reduction in the loss of the has ended up on 2 628.93 tones per year. The final value of transportation of the floodplains without erosion measures was 30 671,77 tones. After changing the sowing technologies and the change in the values for the factors C and P, it decreased to 5 203,32 tones. The results of the diploma thesis show that the water erosion of the soil is a large and frequent problem of many agricultural lands, especially those where soil is left without any protective effect of vegetation and also where the broad-leaved crops are grown. An important factor that can significantly help to reduce erosion is also the right way of the soil cultivation.
92

Faktor vegetačního krytu v kontextu efektivní protierozní ochrany zemědělské půdy

Jovanović, Ivana January 2019 (has links)
Aim of this diploma thesis was to study the protective effect of vegetation from the point of view of the two most common types of erosion in the Czech Republic, water and wind. The theoretical part of the thesis is focused on the degradation processes occurring in the soil, the threat of agricultural land by water and wind erosion, with a focus on wind erosion. Based on the analysis of data from the selected stations, changes in phenological occurrence of selected crops, sugar beet and corn were examined. The issue of changing climate and its influence on the course of wind erosion was characterized. On the other hand, soil erosion control was described based on the rules of GAEC (Good Agricultural and Environmental Conditions) where critical periods of growth of field crops are limited. In the practical part, the Mann-Kendall test was performed; based on this test changes in the onset of phenological phases and agrotechnical operations were found. Furthermore, the areas which are most endangered by wind erosion (Tvrdonice, district Břeclav) were defined, where based on the identification of critical periods field measurements were performed with deflameter and monitoring of erosion occurrence. Subsequently, qualitative parameters of soil particles were found on the basis of the spectral analysis of the deflametric record in the period of dangerous erosion episodes.
93

Stanovení ztráty půdy erozí a návrh protierozních opatření

Gross, Karel January 2017 (has links)
The thesis entitled Determination of soil loss by erosion and erosion control measures proposal deals with the calculation of soil loss by erosion from watershed of Dolnodubňanský stream. First, soil erosion is described generally and possibilities of erosion control measures. Next part is focused on the calculation of erosion risks in the mentioned watershed. The calculation is done using USLE according to Wischmeier and Smith. The calculation was then performed by programs USLE2D, LS converter and ArcGIS. Erosion control measures are then propose depending on the final stage of erosion hazard. All the calculated values are shown graphically in the map outputs.
94

Návrh protierozních opatření v katastrálním území Bořitov

Šmarda, Zbyněk January 2017 (has links)
The thesis called "Design of erosion control measures in the cadastral area of Bořitov" focuses on the issue of soil erosion. Erosion of soil is a natural process in which by working of water, wind, snow, alternatively other agents the surface of soil is eroded, soil fractions are transported and their sedimentation takes place. In my thesis, I concern myself with determination of loss of soil by effect of erosion in the cadastral area of the Bořitov municipality. The thesis is divided into two parts. The first part of the thesis is prepared in the form of a literary research. Based on the study of expert literature, the first part describes the issue of soil erosion and erosion control measures. The second part concerns with an analysis of current conditions and an analysis of the current state of use of the area with respect to its endangerment by water erosion. Further, it evaluates individual erosion factors, determines threat of erosion using an universal equation following Wischmeier and Smith, it designs system of erosion control measures and states effectivity of the designed measures.
95

Studie proveditelnosti krajinářských úprav v lokalitě Slavíky v k.ú. Lubě, bývalý okres Blansko

Pařízek, Jan January 2017 (has links)
The diploma thesis deals with the feasibility studies of landscape management in Lubě village at the area called Slavíky, within the South-Moravian Region. The land ownership by the village Lubě was selected for the study. The several areas of project were chosen for a purpose to strengthen the ecological stability and the possibility of connecting segments of the surrounding landscape. Two versions of project were proposed for each area and subsequently, these two variants were assessed. The first variant was chosen after consultation with the councilors because the second variant referred only about forestry view. In principle was taken into consideration at the multi-functionality of the solution. It consists in limiting erosion, supporting ecological stability, increasing biodiversity of landscape, along with an increase in the carrying capacity of the hunting ground, and enhancement of overall aesthetics around the village Lubě. Finally, everything is focused to the recreational function. The final view of realization is reflected in the design documentation.
96

Návrh komplexního řešení protierozní ochrany v hospodářském obvodu ZD Ploština Loučka

Chovancová, Marie January 1992 (has links)
No description available.
97

Stanovení ztráty půdy erozí a návrh protierozních opatření

Fischerová, Monika January 2016 (has links)
The task of the master's thesis on the topic of "The determination of the loss of the soil erosion and the draft erosion control measures" is the first to describe in general what is soil erosion and erosion control measures, what they may be. Then the work focuses on the calculation of the average long-term loss of soil erosion and loss of soil from torrential rain on the selected watersheds. These steps follows its own draft anti-erosion measures. The measures are designed to reduce the loss of soil found in the basin. The water catchment area, which is the erosion of the watershed is determined, the stream Pradlenka.
98

Vliv změn landcover na konektivitu fluviálních procesů v povodí / The influence of changes of land cover on connectivity of fluvial processes in catchment

Kofroňová, Jitka January 2018 (has links)
The connectivity of fluvial processes or hydrological connectivity are terms often used to describe internal linkages in landscape that intensify/reduce water and sediment fluxes as well as the substances they contain. It is based on the concept of landscape connectivity defined, in particular, by fragmentation of landscape and barriers that obstruct the movement of material. While researches focusing on water erosion or runoff focus on the volume of different fluxes, connectivity reveals new information on catchment functioning as well as reactions to various types of stimuli, and thus represents a more complex phenomenon. This master thesis informs about the topic as a whole, it describes the main forms of its modelling and specific influences that have major impact on presented results. Three approaches of modelling were tested. The main concept lies in evaluation of the index of connectivity, firstly, with approach proposed by Borselli et al. (2008) and implemented in software ArcGIS and secondly, in software SedInConnect 2.0. The third approach is modelling connectivity in software LAPSUS 5.0 that belongs to landscape evolution models. Modelling in LAPSUS proved that using even this indirect method for evaluation of hydrological connectivity is a suitable approach. Selected area for modelling...
99

Stanovení ohroženosti pozemků vodní erozí ve vybraném povodí

Gajárek, Martin January 2014 (has links)
Soil erosion vulnerability of the agricultural soils and basic hydrological characteristics were reconnoitred in Chvalkovický stream basin in Vyškov county. Preparation and the analysis of source data used for evaluation of erosion and hydrological circumstances of the basin were made in ArcGIS 10.0 in software product ArcView using the set of integrated software aplicationes ArcMap, ArcCatalog and ArcToolbox and programmes LS-converter and USLE2D. For make an assessment of soil erosion vulnerability and evaluation of situation after design of erosion control measures was used the universal equation for calculation of long-term loss of the soil caused by water erosion by Wischmeier and Smith (1978).
100

Vyhodnocení ohroženosti pozemků vybraného katastrálního území vodní erozí

Zámečník, Tomáš January 2014 (has links)
This thesis is focused on evaluation of vulnerability of land cadastral area Rovečné water erosion and proposing specific erosion control measures. The intensity of the water erosion was determined by calculating the Universal Soil Loss Equation according Wischmeier and Smith. The calculation of the universal equation and determine the long-term average soil loss by erosion prior to the proposal and the proposal of its own anti-erosion measures was realized through the ArcGIS. Calculating factors universal equation was found that 213.80 ha (26.10% area) occurs very strong erosion, that has been proposed measures completely eliminated. The 156.34 ha (19.08%) there is a strong erosion, on 82.16 ha (10.03%) there is medium erosion and on 366.90 ha (44.79%) is a slight erosion. The proposed anti-erosion measures were mainly the introduction of the minimization tillage the cultivation of crops. For a comprehensive erosion control of area where was persisting increased erosion was designed protective grassing.

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