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Modelling snow accumulation and melting in the Bystřice River basin
Kutláková, Lucie ; Jeníček, Michal (advisor) ; Daňhelka, Jan (referee)
Dealing with the issue of spring flood events is primarily based on their causes. It is therefore important to study the processes of snow accumulation and snowmelt especially in mountain areas where the development of snow water equivalent (SWE) is primarily observed. The snow water equivalent indicates amount of the water in the snow and thus represents a runoff volume during the spring melting period and demonstrates the flood risk potential. In this thesis the lumped modelling approach of the rainfall-runoff model HEC- HMS was used. The model was applied in the Bystřice River basin in the Ore Mountains where the field measurements of the snow cover and SWE is carried out. Applied temperature-index method is the well-developed method because it takes into account both the melting during precipitation and melting in the period without any precipitation and aims to capture snow energy balance by means of air temperature. Three winter periods (2006, 2008 and 2009) were simulated. The evolution of the snow water equivalent was observed and the agreement between observed and simulated hydrographs was assessed in the closure profile Ostrov. Published results show the influence of winter course and character on the model capability to simulate the snow water equivalent and runoff. The observed and...
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Impact of forest disturbances on the runoff in the central Sumava Mts.
Bartůňková, Kristýna ; Langhammer, Jakub (advisor) ; Jeníček, Michal (referee)
Impact of forrest disturbance on the runoff in the central Šumava Mts. ABSTRACT The diploma thesis deals with the influence of forest disturbance, as for example wind and bark beetle calamities, to the runoff characteristics in the central Šumava Mountains. The analysis of five precipitation events and their runoff responses was applied to seven small experimental catchments with different stage of disturbance. Studied catchments were catchments fo Tmavý, Roklanský, Březnický, Javoří, Cikánský, Černohorský potok and Antýgl. Chosen precipitation events belong to the years 2009 and 2010 and to warm half year, when no snow cover can influence the runoff. Similarity of catchments was established by cluster analysis. For comparison of the reaction of single catchments to the same precipitation event was used simple comparison of precipitation and runoff data and waves. Key words: forest disturbance, central Šumava Mountains, rainfall-flow conditions, cluster analysis
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Local scale snow accumulation and ablation variability using high spatial resolution data
Cuřín, Vojtěch ; Jeníček, Michal (advisor) ; Minařík, Robert (referee)
The focus of this bachelor's thesis is snow depth variability at local scale and modern methods of snow depth measurement with high accuracy, precision and resolution. The main goal is to provide an overview of current research in this area, give comparison of the most widely used methods and outline their most appropriate fields of application. A part of this work is also dedicated to an evaluation of snow distribution over a study area in Filipohuťský creek basin in Šumava (Bohemian Forest) and to an assessment of the impact of selected variables on snow depth variability using multiple linear regression models. This is done using manual snow depth measurement data and local digital surface model with high resolution. Multiple linear regression models capture the snow depth variability more precisely than models based on ordinary kriging, nevertheless the regression coefficients of selected predictors are too inconsistent to confirm their effect. Key words: snow depth, photogrammetry, laser scanning, multiple linear regression
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Application of degree-day accumulation and snowmelt model in the Ptačí Brook basin
Beitlerová, Hana ; Jeníček, Michal (advisor) ; Pavlásek, Jiří (referee)
Snow accumulation and snowmelt research is one of the most important hydrological issues in mountain areas World-wide. Spring snowmelt, usually in the combination with intensive rainfall or high air temperature, is one of the most common causes of flooding in the Czech Republic. Mathematical modeling of hydrological processes belongs to effective instruments of flood protection and finds its use in a variety of areas. For example, water management, hydrological forecasts for agriculture, information for dam regulation or for recreational areas and water sports are all affected. This thesis focuses on snow accumulation and snowmelt modeling with use of the empirical Degree-day method. This method is based on the relationship between snowmelt rate and air temperature. The American HAC-HMS programme is used for the simulation of hydrological processes. The main goal of this thesis is to calibrate the model and to simulate snow accumulation, snowmelt and run-off from the watershed. The experimental basin 'Ptačí potok' is situated in the central part of the Šumava Mountains, in altitude of about 1,200 m. Two winter seasons, 2011 and 2012, were simulated. Simulations showed high reliability and correct calibration of the Temperature index snowmelt model. Simulations of the snow water equivalent evolution...
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Modelling the runoff from snowpack in the forest and in open areas
Podzimek, Slávek ; Jeníček, Michal (advisor) ; Langhammer, Jakub (referee)
Modelling the runoff from snowpack in the forest and in open areas Abstract Spring floods are closely related to the issue of snow. It is very important to study the process of snow accumulation and snowmelt in mountainous areas, where the monitoring of the snow water equivalent throughout the winter season is carried out. Snow water equivalent indicates the amount of water bounded in the snow, and therefore it represents a potential danger during snow-melt. The thesis is dealing with snowmelt processes and particularly with the impact of vegetation on the runoff process during snowmelt. The lumped rainfall-runoff model HEC- HMS was used for the modelling. Modelling of snowmelt runoff was carried out by means of degree-day method. The model was applied on the Zlatý Brook catchment in the Ore Mountains. The degree-day method is very sophisticated method and takes into account the snowmelt dynamics during precipitation and snowmelt in the period without any precipitation. The method takes into account the effect of heat emitted by the Earth's surface. The method tries to capture the overall energy balance of snowpack by means of air temperature. The model simulated the evolution of snow water equivalent and discharge in the winter 2009/2010. Simulated discharges were compared with observed ones. After model...
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IMPACT OF DRAINAGE CHANNELS ON RUNOFF REGIME IN FOREST CATCHMENT
Kalkus, Jan ; Kliment, Zdeněk (advisor) ; Jeníček, Michal (referee)
The main task of this diploma thesis is to evaluate function of system of open drainage channels and its impact on runoff from Tetřívčí brook forest catchment in Šumava mountains region, upper basin of the Blanice River. Catchment area is only 1,62 km2 and total length of all channels is over 12 km, so it's very important feature of this catchment. The first task was to explore to explore all the channels and set them to the map. Most of used data were measured manually, only precipitation and water level in main stream were measured by automatic gauges. It's not possible to compare results with state without channels, what is the main obstacle for data analysis. Measured channels normally contribute to total catchment runoff by 6 % to 39 %. About 20 % of channel length participate in runoff process in dry periods, in wet periods it can be even 90 % of channel length, what indicates functionality of drainage system. Actual soil saturation in the catchment is very important factor, it's expressed either by index API 5 (based on precipitation) or by groundwater level in 5 measured in separate drills. It's proved by channels responses in well-saturated periods. Runoff in measured channels raises up significantly after even very small precipitations of 1,7 mm. All results are suggesting, that total...
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Calculation of melt factors in a forest with different structure and in an open area in a small mountain catchment
Hotový, Ondřej ; Jeníček, Michal (advisor) ; Matějka, Ondřej (referee)
This bachelor thesis focuses on the development of snowpack in connection with effects of different physical-geographical factors, especially with the strong influence of vegetation on components of energy balance of the snowpack, including rainfall and runoff regimes of the area. The main aim of this thesis is to investigate the differences in snowmelt characteristics in an open area, under healthy coniferous forest and under forest infected by the bark beetle (Ips typographus). The snow depth and snow water equivalent data were obtained by field measurements at selected study sites in the experimental basin of Ptačí Brook in the Šumava Mountains during winter 2015/2016. The data were evaluated by simple conceptual method based on degree-day approach (temperature index), which examines the relationship between the snowmelt rate and air temperature. According to vegetation, degree-day factors were defined for each type of area as 1.71 mm řC-1 d-1 for healthy coniferous forest, 2.07 mm řC-1 d- 1 in forest infected by the bark beetle and 2.68 mm řC-1 d-1 in an open area. A simple model is a part of the thesis. It predicts the development of snow water equivalents using melt factors and it was used to evaluate the snow storages during snowmelt in study sites. Furthermore, it showed, that the most...
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