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Analysis of snowpack density in mountain catchments in Krušné Mountains and Šumava Mountains
Blšťák, Adam ; Jeníček, Michal (advisor) ; Vlček, Lukáš (referee)
Analysis of snowpack density in mountain catchments in Krušné Mountains and Šumava Mountains Abstract: Mountain catchments are very important sources of fresh water. These areas are characterized with long period of snow cover. The thesis presents analyses of snow density in mountain catchments, focusing mainly on factors and processes influencing its distribution. The data of data recorded in experimental catchments in the Krušné Mountains and the Šumava Mountains through 2010 - 2014 are compared with findings given in different scientific articles and studies. The thesis examines the influence of several factors on snow density. It is first of all the influence of snow depth, as well as the influence of vegetation, the development of density in time, and the development of snowpack density in relation to the snow water equivalent. The results of the research show that snowpack density gradually increases with snow depth. The highest density occurs on open plains and in damaged forests. Density also increases with time. The highest density can be observed towards the end of winter, in March and April. Keywords: snow density, snow depth, snow cover, mountain catchments
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Effect of canopy interception on snow accumulation at selected alpine localities in the Czech Republic
Nedělčev, Ondřej ; Jeníček, Michal (advisor) ; Falátková, Kristýna (referee)
This bachelor thesis analyzes the impact of canopy interception on snow accumulation. In the first part of the thesis, available literature about interception of snowfall on forest canopy is reviewed. In the second part of thesis, the reader is acquainted with the analysis concerning the effects of forest cover on snow accumulation. The thesis compares snow water equivalent under forest stands with different canopy density, under a disturbed forest due to bark beetle forest with snow water equivalent in adjacent open areas. Snow water equivalent in accumulation period in forest is 28% lower than snow water equivalent in open area. Ratio of snow water equivalent in forest to snow water equivalent in open area during accumulation period does not significantly change. Linear regression was used to describe the relationship between snow water equivalent and canopy density. The findings obtained from the regression show that snow water equivalent decreases with increasing canopy density.
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Influence of catchment spatial subdivision on the accuracy of the snow accumulation and snowmelt model
Hájková, Barbora ; Jeníček, Michal (advisor) ; Šípek, Václav (referee)
Influence of catchment spatial subdivision on the accuracy of the snow accumulation and snowmelt model Abstract This thesis is focused on influence of catchment spatial subdivision on the accuracy of rainfall-runoff model simulations. A hydrological model HEC-HMS developed by U.S. Army Corps of Engineers was applied in the thesis. Study area includes two experimental catchments; Bystřice River basin and Zlatý Brook basin. Both catchments are located in the Krušné Mountains. The research in catchments has been carried out by the Department of Physical Geography and Geoecology since 2008. The influence of four different horizontal and vertical catchments delineation on runoff simulations was analyzed. The simulations were performed in two two-year periods 11/2008-10/2010 and 11/2010-10/2012. The attention was mainly aimed to snowmelt component of the model, for which temperature index method was chosen. The results of simulations were compared with water stages data measured in catchments outlets and with data from winter field measurements (snow depth and snow water equivalent). The results from both catchments showed that higher accuracy of simulation of the snow water equivalent was reached by dividing the catchments into more elevation zones. However, each of the catchments behaved in different way. The...
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Analysis of snowpack density in mountain catchments in Krušné Mountains and Šumava Mountains
Blšťák, Adam ; Jeníček, Michal (advisor) ; Vlček, Lukáš (referee)
Analysis of snowpack density in mountain catchments in Krušné Mountains and Šumava Mountains Abstract: Mountain catchments are very important sources of fresh water. These areas are characterized with long period of snow cover. The thesis presents analyses of snow density in mountain catchments, focusing mainly on factors and processes influencing its distribution. The data of data recorded in experimental catchments in the Krušné Mountains and the Šumava Mountains through 2010 - 2014 are compared with findings given in different scientific articles and studies. The thesis examines the influence of several factors on snow density. It is first of all the influence of snow depth, as well as the influence of vegetation, the development of density in time, and the development of snowpack density in relation to the snow water equivalent. The results of the research show that snowpack density gradually increases with snow depth. The highest density occurs on open plains and in damaged forests. Density also increases with time. The highest density can be observed towards the end of winter, in March and April. Keywords: snow density, snow depth, snow cover, mountain catchments
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Snow depth variability at the plot scale: Assesment of topography and vegetation influence
Murdychová, Pavlína ; Jeníček, Michal (advisor) ; Pevná, Hana (referee)
Snow depth variability at the plot scale: Assesment of topography and vegetation influence Abstract This master thesis deals with the evaluation of snow depth variability at the plot scale. It focuses on influence of topography and vegetation factors as slope, exposure, curvature, solar radiation and leaf area index. There is also assesment the impact of the size scale. Measurement was carried out in period of accumulation and snowmelt in winter 2014/2015 in the Krkonoše Mountains on Hanapetrova glade. To evaluate the effect of selected factors on variability of snow depth there was used multiple linear regresion and other descriptive statistical methods. The research shows that the variability of snow depth during the accumulation is greater in forest which is probably due to vegetation. The dependency was not confirmed by regression analysis. Higher variability of snow cover in the forest was also observed in the melting period. The variability of snow cover increased in the forest in general. The results show that the snow depth variability decreasses with increasing grid size. Keywords: snow accumulation, snowmelt, topography, vegetation, multivariate analysis
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An energy-based model accounting for snow accumulation and snowmelt in a coniferous forest and in an open area
Matějka, Ondřej ; Jeníček, Michal (advisor) ; Langhammer, Jakub (referee)
An energy-based model accounting for snow accumulation and snowmelt in a coniferous forest and in an open area An energy balance approach was used to simulate snow water equivalent (SWE) evolution in an open area, forest clearing and coniferous forest during winter seasons 2011/12 and 2012/13 in the Bystřice River basin (Krušné Mountains). The aim was to describe the impact of vegetation on snow accumulation and snowmelt under different forest canopy structure and density of trees. Hemispherical photographs were used to describe the forest canopy structure. Energy balance model of snow accumulation and melt was set up. For forest sites the snow model was altered for accounting the effects of the forest canopy on the driving meteorological variables of the snow model. Leaf area index derived from 32 hemispherical photographs of the vegetation and sky was used for forest influence implementation in the snow model. The model was evaluated using snow depth and SWE field data measured at 16 localities in winter seasons from 2011 to 2013. The model was able to reproduce the SWE evolution in both winter seasons beneath the forest canopy, forest clearing and open area with correlations to observations ranging from 0.16 to 0.99. The SWE maximum in forest sites is by 18% lower than in open areas and forest...
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Effect of canopy interception on snow accumulation at selected alpine localities in the Czech Republic
Nedělčev, Ondřej ; Jeníček, Michal (advisor) ; Falátková, Kristýna (referee)
This bachelor thesis analyzes the impact of canopy interception on snow accumulation. In the first part of the thesis, available literature about interception of snowfall on forest canopy is reviewed. In the second part of thesis, the reader is acquainted with the analysis concerning the effects of forest cover on snow accumulation. The thesis compares snow water equivalent under forest stands with different canopy density, under a disturbed forest due to bark beetle forest with snow water equivalent in adjacent open areas. Snow water equivalent in accumulation period in forest is 28% lower than snow water equivalent in open area. Ratio of snow water equivalent in forest to snow water equivalent in open area during accumulation period does not significantly change. Linear regression was used to describe the relationship between snow water equivalent and canopy density. The findings obtained from the regression show that snow water equivalent decreases with increasing canopy density.
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Influence of catchment spatial subdivision on the accuracy of the snow accumulation and snowmelt model
Hájková, Barbora ; Jeníček, Michal (advisor) ; Šípek, Václav (referee)
Influence of catchment spatial subdivision on the accuracy of the snow accumulation and snowmelt model Abstract This thesis is focused on influence of catchment spatial subdivision on the accuracy of rainfall-runoff model simulations. A hydrological model HEC-HMS developed by U.S. Army Corps of Engineers was applied in the thesis. Study area includes two experimental catchments; Bystřice River basin and Zlatý Brook basin. Both catchments are located in the Krušné Mountains. The research in catchments has been carried out by the Department of Physical Geography and Geoecology since 2008. The influence of four different horizontal and vertical catchments delineation on runoff simulations was analyzed. The simulations were performed in two two-year periods 11/2008-10/2010 and 11/2010-10/2012. The attention was mainly aimed to snowmelt component of the model, for which temperature index method was chosen. The results of simulations were compared with water stages data measured in catchments outlets and with data from winter field measurements (snow depth and snow water equivalent). The results from both catchments showed that higher accuracy of simulation of the snow water equivalent was reached by dividing the catchments into more elevation zones. However, each of the catchments behaved in different way. The...
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Application of the Snowmelt Runoff Model for snow accumulation and snowmelt modelling in experimental catchments Bystřice and Zlatý Brook in the Krušné Mountains
Šedivá, Kateřina ; Jeníček, Michal (advisor) ; Ducháček, Libor (referee)
Title: Application of the Snowmelt Runoff Model for snow accumulation and snowmelt modelling in experimental catchments Bystřice and Zlatý Brook in the Krušné Mountains Modelling of hydrological processes is a dynamically developing part of hydrology. The Snowmelt Runoff Model (SRM) was applied for modelling the runoff in two experimental catchments Bystřice and Zlatý Brook. The aim of this thesis is to set up and calibrate SRM model and to evaluate methods and procedures used for runoff simulations. The SRM model was used for modelling snow accumulation and snowmelt in two selected catchments in the Krušné Mountains. The snow depths and snow water equivalents are measured since 2009 at selected locations situated in catchments. Calibration and validation of the model was based on continual time series of precipitation, air temperature and discharge measured 2009. Hydrological years 2009 and 2010 were used for model calibration and hydrological years 2011 and 2012 were used for model validation. Sensitivity analysis, which quantifies the effect of individual model parameters on the simulating proces, was carried out based on results. Recession coefficient and runoff coefficient belong to the most sensitive parameters with highest impact on runoff simulations. Model calibration was successful, which...
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