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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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Hydrological processes and dynamics in the changing climate and environment: Lessons learned from multiple temporal and spatial scales
Su, Ye ; Langhammer, Jakub (advisor) ; Hanel, Martin (referee) ; van Meerveld, Hilda (referee)
Hydrological processes and dynamics in the changing climate and environment: Lessons learned from multiple temporal and spatial scales Ye Su ABSTRACT Climate change, along with the changes in land use and land cover (LULC), is the key factor driving the changes in hydrological processes and dynamics in a basin. This thesis emphasized on understanding the impact of both long-term climate change and abrupt anthropogenic driven agricultural intensification or natural driven insect-induced forest disturbance on hydrological processes and dynamics at varying spatial and temporal scales in two diverting terrestrial environment. Two pattern-based investigations, one case study in a forest region in Central Europe and another in a semi-arid region in Central Asia, were aimed to answer the main research question "what are the responses of hydrological dynamics and the related hydro-geochemical conditions to climate change and certain changes in LULC at a basin-scale?". The long-term hydro-climatic dataset was used for conducting statistical analyses and establishing hydro-climatic modelling at the basin scale. We further conducted process-based studies, attempting to understand how and why the specific hydrological dynamics were altered at smaller spatial and temporal scales: (i) a catchment-scale tracer-based...
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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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Changes of rainfall-runoff conditions and anthropogenic modification in Lomnice River basin
Bažatová, Tereza ; Šobr, Miroslav (advisor) ; Langhammer, Jakub (referee)
The runoff from a landscape is a natural process which is very complicated. It's not simple to express the runoff process in general because it depends on many factors that participate more or less in its course. The main aim of this paper is the explanation of rainfall-runoff process in Lomnice River basin, the land use changes description and the evaluation of anthropogenic modifications of Lomnice River. All of these elements influence the course of hydrological extremes. Another parts of this thesis concentrate on floods (especially flood 2002) in the Lomnice River basin and on water systems of Blatensko which is the third largest of all water systems in the Czech Republic. The relationship between a rainfall and a runoff in Lomnice River basin is being assessed with the help of the simple- and double-mass curve method, regarding possible changes caused by anthropogenic impacts. This part contains the analysis of trend in development of land use, the analysis of air temperature and snow parametres as well. Great anthropogenic changes of river channels and river floodplain can evoke dramatic geomorphological effects. The methodology of research - anthropogenic modifications of Lomnice River is based on a field survey of anthropogenic transformation of a riverbed and river floodplain. Then the...
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Water quality change in small watersheds after sewage water treatment plant building
Rödlová, Sylva ; Langhammer, Jakub (advisor) ; Kvítek, Tomáš (referee) ; Pechar, Libor (referee)
Změny kvality vody v malých tocích, vyvolané vybudováním čistírny odpadních vod, představují doposud málo studované a přitom velmi aktuální téma současné hydrologie. Tato studie se zabývá popsáním těchto změn a faktorů, které je ovlivňují. Pro účely výzkumu bylo vybráno pět malých, zemědělsky využívaných povodí prvního řádu (čtyři povodí průměrně 6 km2 , jedno 16 km2 ). V každém zájmovém území byla vždy jedna vesnice od 640 do 2 500 obyvatel. Během 7 - 16 let trvajícího měsíčního monitoringu základních indikátorů kvality vody (O2, BSK5, CHSKCr, TOC, konduktivita, N-NH4, N-NO2, N-NO3, PC, P-PO4) byla zachycena stavba čistíren v obcích. Spolu s daty o účinnosti čistíren byly vyhodnoceny změny kvality vody v toku. Identifikované typy změn ukazují na problematické aspekty vývoje kvality vody v malých povodích. Kromě očekávaného rychlého a razantního snížení hodnot zátěže po výstavbě čistírny odpadních vod se vyskytují i odlišné projevy změn - pouze mírné snížení zátěže, stagnace, dokonce i zvýšení koncentrací sledovaných indikátorů. Mezi další typické změny patří navýšení hodnot 1-2 roky před uvedením čistírny do provozu a opožděná nitrifikace v toku způsobená nevhodným provozem čistírny. Mezi nejdůležitější faktory ovlivňující změny patří provoz čistírny, velikost průtoku recipientu, zemědělské...
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