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Dissolved and gaseous nitrogen losses in forests controlled by soil nutrient stoichiometry
Oulehle, Filip ; Chuman, T. ; Hruška, Jakub ; Krám, Pavel ; Navrátil, Tomáš ; Tesař, Miroslav ; Ač, Alexander ; Urban, Otmar
This study investigates the consequences of chronic nitrogen deposition in forests, including its effects on soil and surface water quality, and greenhouse gas emissions. To predict these effects, the authors explore the controls over dissolved and gaseous nitrogen fluxes in temperate forests. Their findings indicate that stream leaching losses of dissolved nitrogen correspond with the nutrient stoichiometry\nof the forest floor, with stream N losses increasing as ecosystems progress towards phosphorus limitation. Soil nitrogen storage increases with oxalate extractable iron and aluminium content. The authors estimate soil gaseous losses based on 15 N stocks, which averaged 2.5±2.2 kg N ha-1 year-1 , comprising 20±14% of total nitrogen deposition. They also extrapolate the current gaseous nitrogen loss flux from forests globally to be 8.9 Tg N year-1 , which represents 39% of current nitrogen deposition to forests worldwide.
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The influence of landscape changes on erosion and runoff
Uhrová, Jana ; Toman,, František (referee) ; Váchal,, JAN (referee) ; Dumbrovský, Miroslav (advisor)
The aim of this thesis is to evaluate the influence of land use changes on erosion and runoff conditions. For the purpose of the evaluation, two catchments with different areas and pedological characteristics were selected (the catchment of the river Luha and the catchment of the Hubenov reservoir). In these catchments, a comparison of 26 selected land covers was conducted. The individual land covers were evaluated first in four seasons of the 1950s and 1990s, second according to the today's status of landscape by means of a detailed yearly evaluation conducted between 2002 and 2013, and third according to a land cover conceptual design. Analyses of not only land cover, but also geomorphological, pedological and hydrological conditions were carried out for both of the catchments by means of geographic information system (GIS) tools. The quantification of soil loss was performed by means of two methods – the method USLE with the use of ArcGIS program and the soil loss model WEPP. The crucial factor of the runoff evaluation of the preset end profiles with respect to the formation of concentrated runoffs and their catchment areas was the hydrological model DesQ-MAXQ. The selected land cover scenarios of the river Luha were then exposed to the conditions of a real rainfall that occurred in 2009 and that resulted in floods in the area. Furthermore, a rainfall-runoff model was created for this catchment area in HEC-HMS; the land cover scenarios were again subjected to the above-mentioned real rainfall. The land use changes of the catchment area of the reservoir Hubenov were assessed also with respect to the concentration of substances in the profiles studied.
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Design precipitation in Czech river basins
Müller, Miloslav ; Kašpar, Marek ; Hulec, Filip
Data on rainfall intensity on the territory of the Czech Republic with a horizontal resolution of 1 km2 and a time step of 10 minutes, obtained by adjusting radar estimates with data from rain gauge stations, were used to derive design areal precipitation in the Czech river basins of 1st to 4th order and in the basins of surface water bodies. When the rainfall accumulation time is doubled, the design precipitation total in individual pixels increases by about 20% on average. The magnitude of the design totals decreases with increasing catchment area, especially for shorter accumulation periods.
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Precipitation and water runoff in the catchment with mosaic of arable land, forests and built-up areas
SCHWARZOVÁ, Monika
This thesis examines the influence of land cover and land use on rainfall-runoff patterns in small catchments. The literature review presented the rainfall-runoff process in general, runoff and the factors that influence runoff. In the practical part of the thesis, the different months of the 2018 study period were presented and converted into graphical form and the differences in rainfall-runoff ratios for two delineated small catchments with significantly different landscape cover were discussed. Specific surface water runoff from catchments with purely forest cover and catchments with a mosaic of cropland, forest, grassland and built-up areas were compared. Runoff responses to rainfall events were also monitored. Measurements of water level in the watercourse with an ultrasonic water level sensor and measurements of water velocity in the watercourse with a hydrometric propeller were used to calculate specific runoff rates. A boat rain gauge was used to measure precipitation. The results showed that the specific runoff from watersheds with forest cover is generally lower and slower due to interception and increased surface roughness compared to runoff from watersheds with a mosaic of cropland, forest, grassland and developed areas. Forest cover in the catchment reduces and slows runoff, particularly during shortterm significant rainfall episodes, and helps to maintain stable runoff from the landscape during drought episodes. In general, the results indicate the importance of vegetation in the landscape for its hydrological characteristics. Finally, modifications to improve the conditions in these small catchments were suggested.
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The Development of Relation on the revitalizated Stream
PÁVOVÁ, Jitka
In order to water relation regenetation the government of the Czech Republic enforced the Program of revitalization water systems in the year 1992. This program has been used in the catchment of Volavecký stream. In years 2000 {--} 2001 the part of these stream was revitalizated. The object of revitalization was connection of the aqueous media and the surrounding landscape. The objective of these works are examination of revitalization and project of the revitalization and financing. There were used knowledges from a lot of brages, for example nature conservation, erosive protection, ecological network and land consolidation.
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Comparison of precipitation and discharges in relation to nitrate concentrations in the Jenínský stream catchment.
VRZÁK, Zbyněk
This work deals with comparison of precipitation and discharges in relation to nitrate concentrations in the Jenínský stream. The locality is situated on the east of town Vyšší Brod in the southern part of Bohemia. Since the 80`s this small catchment is research area and in the year 2004 The Faculty of Agriculture has continued in this research in Jenínský stream catchment. The backgrounds for this work are data of hydrological year 2006 which are gained from continuous measuring and scanning in small catchment Jenín. There is a recurrency to generalize the precipitation impact which induce changes of discharges on the closing device in small catchment.
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Mapping of the Litavka catchment using GPS
Hojcsková, Daniela ; Matějíček, Luboš (advisor) ; Brůna, Josef (referee)
This thesis is aimed on the study of Global Positioning System (GPS) and its utilization possibilities in nature sciences such as ecology, hydrology, botany and the others. The main contribution of this work is the investigation of current possibilities of the most accurate data collection by using GPS and their subsequent processing in GIS with focus on small catchment. Other methods of terrain data collection are described and compared with GPS in this work, as well. Practical part of the thesis focuses on characteristics of the locality, technical equipment and data editing gained in terrain. The study locality is the Litavka catchment, which is situated in Brdy. The geographical ground data, were gained from ZABAGED and were completed with results of own measuring in terrain. The output of the thesis is the digital terrain model of upper stream of the Litavka River modified by interpolation. Key words: GPS, DTM, GIS, mapping, catchment, Litavka, interpolation
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Optimization of digital river network and its impact on catchment water management
Hošek, Zdeněk ; Matoušková, Milada (advisor) ; Šípek, Václav (referee)
Digital river network dataset is an important source of information in any aspect of water management decision making. It is also a base for modelling or scientific research in many different fields. Development of the dataset in the Czech Republic had been fragmented in a past and as a result three different datasets have been developed that cover the whole of the state's territory. The datasets contain different geometries, different and often conflicting attributes and serve different purposes. Today the time has come that water management decision makers have realised that the situation is no longer sustainable and make effort to merge the datasets into one. The task brings in several technical issues and a potential for severe legal consequences. The aim of this study is to develop a methodological approach to merging the existing datasets into one. This methodological approach to decision which of the conflicting or different attributes should be adopted is based on assumption that the existing datasets will be merged into one consisting the best of all. Comparison of features in the existing dataset will inevitably lead to many conflicts when it will be necessary to decide which of the considered features should be adopted to the resulting dataset. The study considers the main purposes which...
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Processing a landscape revitalization study in a selected catchment
LEXOVÁ, Veronika
This work deals with the revitalization of the Jenínský stream, the revitalization is mainly focused on the separation of pipes from some parts of the stream. The new track of the stream including a vegetation is proposed at its spring. The revitalization also concerns the drainage system, where a new drainage trail and a retention tank are proposed. For the appropriate design of the flow capacity, drainage of water from the river catchment was calculated and the flow and concentration of the substances in the stream were analyzed. Water, its composition and hydrological cycle are generally described in the literary research. It also explains the collision-draining process and the factors that affect it. Theoretic part deals with the revitalization of watercourses and, lastly, drainage systems are described.
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Optimization of digital river network and its impact on catchment water management
Hošek, Zdeněk ; Matoušková, Milada (advisor) ; Šípek, Václav (referee)
Digital river network dataset is an important source of information in any aspect of water management decision making. It is also a base for modelling or scientific research in many different fields. Development of the dataset in the Czech Republic had been fragmented in a past and as a result three different datasets have been developed that cover the whole of the state's territory. The datasets contain different geometries, different and often conflicting attributes and serve different purposes. Today the time has come that water management decision makers have realised that the situation is no longer sustainable and make effort to merge the datasets into one. The task brings in several technical issues and a potential for severe legal consequences. The aim of this study is to develop a methodological approach to merging the existing datasets into one. This methodological approach to decision which of the conflicting or different attributes should be adopted is based on assumption that the existing datasets will be merged into one consisting the best of all. Comparison of features in the existing dataset will inevitably lead to many conflicts when it will be necessary to decide which of the considered features should be adopted to the resulting dataset. The study considers the main purposes which...
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