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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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Melt rates calculation with respect to meteorological conditions
Šťovíček, Vít ; Jeníček, Michal (advisor) ; Hotový, Ondřej (referee)
Meteorological conditions are an important factor affecting the speed of snowmelt. Their impacts have been changing accroding to physical-geographical factors such as elevation, slope of the terrain, slope orientation and vegetation, affecting energy balance of the snowpack. The calculations were made using data from four automatic stations in the Šumava Mountains, namely the Vydra river-basin. These stations measure individual meteorological aspect and snow properties. Based on these data and pre-defined conditions, 136 melting events were selected. The melt factors were calculated based on degree-day approach. Similarly, the melt rates were calculated from the snow water equivalent decrease and snowmelt event duration for each snowmelt event. The correlation and regression analyzes were used to determine the effect of each meteorological factor on the snowmelt speed. The analyses proved the highest dependence of the snowmelt speed on the precipitation amount (the value of the Spearman's rank correlation coefficient rs reached 0.54 for the melt factor and 0.68 for melt rate). There is more substantial difference in the effects of meteorological conditions if we compare the winter season from November to February and the spring snowmelt season from March to May, while the highest snowmelt...
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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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Methods of modelling the runoff from snow cover. Case study: Headwater area of Bystřice River
Hasa, Martin ; Jeníček, Michal (advisor) ; Taufmannová, Alice (referee)
This bachelor thesis deals with the issue of modelling the runoff from melting snow. The main objective is to evaluate two basic methods: degree-day approach and energy balance method. Part of the thesis is the application of degree-day approach in the headwater area of Bystřice River in the Krušné Mountains. Degree day factors were calculated using air temperature and flow rates in the closure profile for the spring snowmelt period in years 2009 and 2010. Degree Day factors were used for modelling the runoff from melting snow. Study results were compared with the findings published in the literature. Key words: temperature index, degree-day approach, energy balance of snow cover, snowmelt modelling
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