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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.
121

Vyhodnocení srážkových úhrnů ovlivňujících erozní splachy ve vybraném povodí. / Evaluation of total rainfall influencing erosion flushes in the catchment.

ŠEFL, Jakub January 2011 (has links)
The aim of the thesis is a calculation of erosion flushes of the catchment of Malče - Budský stream. The surveyed stream flows through the Soběnov highland area of Besednice, Malče and Soběnov municipalities. The thesis also describes the water catchment model from pedological, geological and climatological perspective. The main objective is to compare different calculation methods of erosion flushes in the catchment. The comparison covers the Universal Soil Loss Equation by Wischmeier and Smith and the CN (Curve Number) Method, which is used for the total runoff and culminating flow calculation. A modified Universal Soil Loss Equation by Williams and Berndt is used to determine the erosion flushes. The results of both methods mentioned above are compared at the conclusion of the thesis.
122

Vliv uspořádání krajiny na erozní a odtokové poměry v k.ú. Stará Ves u Bílovce / Influence of landscape structure on the runoff and erosion condition in Stará Ves u Bílovce

Lízalová, Zuzana January 2014 (has links)
This thesis deals with the influence of the landscape structure on the erosion and runoff conditions. The aim of the thesis is to analyze the erosion and runoff conditions of the landscape in the area of Stará Ves by Bílovec for three different time periods and for the design condition. The thesis is divided into four parts, the first part is theoretical, dealing with erosion and runoff conditions in the form of research. The second part analyzes the current state of the area. The third part of the thesis defines and evaluates the erosion wash off and runoff condiditons for given variations. The last part deals with the development of the land use from 1957 to the present.
123

Matematický model vývoje propustnosti puklinového prostředí následkem vnitřní eroze a depozice. / Matematical model of permeability evolution in a fractured porous media due to internal erosion and deposition.

Krajinová, Markéta January 2020 (has links)
The seepage of fluid through saturated porous media may lead to inner erosion, channelization, preferential flow and transport and deposition of particles. A novel mathematical model was created to describe some of the processes. The model describes a temporal and spatial development of porosity (volume fraction) and permeability (transmissivity) due to erosion and deposition in saturated porous and fractured media. The model calculates the change of permeability and porosity in a direction of different fracture joint sets. The model is based on multi-continua theory, where a region is divided into components (three or more components in this thesis). The components are described by separate differential equations. This approach was used recently by Mahadevan et al. (2012) and Fujisawa et al. (2009) for erosion of porous media. This thesis describes the approaches, assumptions and the equations used in the model. In contrast to the published models, the thesis considers anisotropy. It is characterized by transmissivity tensor (also hydraulic conductivity tensor), which is composed of vectors in the joint sets directions. The model also uses a Dupuit approximation, which allows to approximate flow onto a horizontal plane. The model is also introduced by a numerical simulation using final element...
124

Optimalizace uspořádání krajiny modelového území

Machová, Alexandra January 2019 (has links)
The Diplom Thesis deals with the possibilities of agricultural landscape optimization in model area Polička and Pomezí to Pardubice Region. The literary overview attention is paid to the historical development of agriculture, the current state of soil in the Czech Republic and the possibility of improving the current state, especially in the form of land consolidation. In the practical part of the thesis, problematic places of the territory were defined on the basis of detailed analysis. The result of the work is a map of the design of optimization measures and recommendations for recommendations especially for users of agricultural land. The study itself should serve as a basis for possible land consolidation or other landscaping.
125

Problémy současného rozvoje vesnických sídel a možnosti jejich řešení

Kuklová, Alexandra January 2019 (has links)
The thesis deals with the current state of the countryside. Especially the issues related to agricultural landscapes and their shortcomings and other related issues. Literature search, in addition to the general description of the contemporary countryside, its condition and functions, the literature search is also dedicated to the countryside of the South Moravian Region, which is then related to the selected model object Tvrdonice, which is located in this region. Literature search also seeks to outline the above-mentioned issues of agricultural landscapes and to focus on possible solutions. One of the main problems is the perception of wind erosion and the poor and dysfunctional condition of many existing windbreaks. That is why a part of the proposals focusing on the gradual renewal of existing windbreaks and proposing their new network are also addressed. The design section is also dedicated to wetland, mainly to exploit landscape potential and increase the ecological stability of the area and to support biodiversity.
126

Analýza ohroženosti pozemků vodní erozí ve vybraném území s využitím programu ArcGIS

Šabata, Tomáš January 2018 (has links)
The diploma thesis is focused on evaluation of the average long-term loss of soil by water erosion in the cadastral areas of Oslavany and Padochov. To determine the erosi-on risk of agricultural land before and after proposal of anti-erosion measures, the uni-versal USLE equation according to Wischmeier and Smith was used. The programs ArcGIS, LS CONVENTER, USLE 2D and MS Excel were used to calculate individual factors. All the map documentation was created by using the program ArcGIS.
127

Praktické využití technologie pásového zpracování půdy v zemědělském podniku

Vaňous, Jaroslav January 2019 (has links)
The diploma thesis deals with the characteristics of maize, one of the most widely grown cereals in the world. Depending on the tightening of European legislation, there is an increasing emphasis on protecting soil from water erosion. For this reason, we are looking for ways to grow widescreen crops on erosion-endangered soils. One of the possibilities is to use the technology of Strip-till, which comes from North America. The main part of the thesis is devoted to the establishment of pilot-run experiments using the Strip-Till technology, their comparison with the conventional full-scale processing and evaluation of results. Finally, the economic demands of the technologies used are calculated and the results are compared with the findings of other authors. All experiments were carried out in the cadastre of the Agricultural Cooperative in Sloupnice using its own technology. The results serve the company as a feedback on the use of Strip-Till in the erosion-threatened conditions in which the farm operates.
128

Soil erosion as a consequence of forest fires in Portugal. Serra da Freita case study.

Lobo, Eduardo January 2018 (has links)
Portugal is one of the Mediterranean countries that besides its natural condition to occur forest fires, has had an increase of forest fires during the last decades and has a consequence the increase of the burned surface and the costs associated, economic, social and environmental. This study case took place in Serra da Freita, a mountain region in the north of Portugal in the Aveiro District. The aim of this case study was to establish a relation between forest fires, erosion and social consequences for the region. For this purpose, a mixed approach was used with Remote sensing to acquire burn severity (dNBR) by comparing the areas before and after forest fires, soil analyses, and with a questionnaire to the local community to comprehend how they are affected. The results obtained permits to understand that not only the forest fires have a direct impact on the soil erosion, but also affect the local community by promoting the abandonment of the area.
129

Návrh protierozních opatření v lokalitě Obecní

Krejsa, Jan January 2019 (has links)
The diploma thesis deals with the proposal of erosion control measures in the locality „Obecní“ in the catastrade area of the city Letohrad. Evaluating the current state of the study site was carried out using fieldwork and digital data processing. Subsequently, suitable anti-erosion measures to remedy the gully was performed. One of the main outputs of the thesis is the drawing documentation together with situational drawings and maps. The main output of the diploma thesis is a design of a system of check-dams including calculations and budget. An integral part of the thesis is also the recommendation of suitable farming on the surrounding agricultural land. The set of proposed measures and recommendations will help to improve the current issue regarding erosion control measures in the study area.
130

Přelévání korporátních zisků a eroze základu daně v kontextu EU

Valešová, Dana January 2019 (has links)
This diploma thesis deals with the extent of the erosion of tax bases and the spillover of corporate profits into countries with preferential tax regimes within commercial corporations and their subsidiaries based in the EU.

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