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The proposal parameters of the small water reservoir in GIS environment.
Feltl, Jakub ; Ivana,, Kameníčková (referee) ; Doležal, Petr (advisor)
This report deals with rainfall-runoff modeling and small water reservoir projection with usage of modern software equipments (GIS, HEC-HMS), using maximum number of available data sources (BPEJ, LPIS, N-year rainfall gages, 3D contours …). The advantage of this method is that it is possible to predict the shape of hydrograph and flood wave volume as well. Other methods cannot offer judgment of flood wave volume and hydrograph shape as this method does. The most important thing in small water reservoir projection is the flood wave volume value, which is undervalued nowadays using wrong evaluation. This method’s advantage is variability of scenarios depending on soil surface, used agricultures, hydraulic and hydrologic parameters etc.
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Modeling hydrological response of the catchment to various precipitation events
ŠVANDA, Dominik
This thesis deals with the simulation of the hydrological response of a river basin to various precipitation events. The hydrological response was simulated in the Olešenský brook basin. The outflow of water from the landscape is influenced by many different factors at the same time. Among the most important factors are, for example, the slope of the terrain, land use, saturation of the soil profile withwater, anthropogenic influences, vegetation cover and last but not least the geological and soil conditions, the shape and area of the river basin, climatic conditions etc. explained and described in detail. Several methods are used to calculate the water runoff from the landscape, in which case the CN curve method was used to calculate the direct runoff from the landscape. By using the BPEJ map, land use and maximum daily precipitation totals with a probability of repeating N years (2, 10, 20, 50 and 100 years) obtained from the rainfall station Týn nad Vltavou, calculations were performed first in a numerical (vector) way and then the maps of direct water runoff from the catchment area were created in a raster way performed in ArcMap software. In the next step, various scenarios were simulated that influenced the outflow of water from the catchment. The first scenario was a change in soil saturation with water, resp. water content in the soil (dry, medium and wet). It has been found that the outflow of water from the basin and the peak flow were both fundamentally changed. Second scenario was grassing of all arable land in the basin, where the actual state compared to the theoretical state. This change reduced the CN curve values, what in turn reduced the direct water runoff from the landscape. Third and the last scenario was the concept of 20 metres wide infiltration strips along roads, watercourses and water areas. The proposed measure reduced the runoff coefficient values by about 1 % compared to the runoff coefficients at the actual state. In this case, there was no fundamental change as the strips occupy only a small part of the total area. However, infiltration strips still have a positive effect on rainfall-runoff events in the landscape.
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Event-based rainfall-runoff modelling of the selected river basin
TICHÁČEK, Pavel
This thesis deals with the event-based rainfall-runoff modelling of the selected river basin. This thesis is based on my previous work "Factors affecting the water discharge from the river basin during rainfall-runoff events". In that work I described factors, which have effect on water runoff from the river basin. This thesis was solved on basin of Jílecký stream. Water runoff from basin is affected with a number of factors, the most significant are slope of the terrain, soil saturation, geological and pedological conditions, vegetation cover and anthropogenic influence. Calculations of direct runoff were realised with method of CN curves, with using BPEJ map, land use map gained from Corine Land Cover 2006 and maximum daily precipitation sums with 2, 10, 20, 50 and 100 years probabilities recurrence obtained from the rainfall station Netřebice. Calculations were performed in a numerical method using vector data and a raster method performed in ArcMap. In the next step I performed simulations of various scenarios of change in river basic characteristics such as soil saturation change, grassing of arable land with a slope greater than 12°, grassing of all arable land and enlargement the built-up area in the river basin.
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The proposal parameters of the small water reservoir in GIS environment.
Feltl, Jakub ; Ivana,, Kameníčková (referee) ; Doležal, Petr (advisor)
This report deals with rainfall-runoff modeling and small water reservoir projection with usage of modern software equipments (GIS, HEC-HMS), using maximum number of available data sources (BPEJ, LPIS, N-year rainfall gages, 3D contours …). The advantage of this method is that it is possible to predict the shape of hydrograph and flood wave volume as well. Other methods cannot offer judgment of flood wave volume and hydrograph shape as this method does. The most important thing in small water reservoir projection is the flood wave volume value, which is undervalued nowadays using wrong evaluation. This method’s advantage is variability of scenarios depending on soil surface, used agricultures, hydraulic and hydrologic parameters etc.
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Comparison of selected methods of calculating baseflow in a small basin and evaluate influnence of baseflow to concentrations of phosphorus in total runoff.
ŠVARCOVÁ, Eliška
This thesis is focused on the methods of separation of baseflow and comparing of these metods. It is analyzing concentrations of total phosphorus in the total runoff and influence of baseflow to concentrations of phosphorus in total runoff. The studied area is subcatchment P52 in the catchment Kopaninský flow. Subcatchments P52 is small (64,93 hectares), drained agro-forestry catchment in Českomoravská vrchovina (Czech-Moravian highlands), with a large proportion of forest area (64% forest and 31% of arable land). Studied the period is hydrological period 2009 - 2011. To obtain the necessary results are used daily flow, daily concentrations, daily precipitation of rain gauge station Velký Rybník and monthly precipitation from rain gauge stations of the ČHMŮ (Czech Hydrometeorological Institute) in Humpolec. For the separation of the baseflow and comparison of methods were selected five methods: - method of digital filter according to Chapman (1999), - method UKIH designed by Institute of hydrology (1980), - method RDF proposed by LINE AND Hollick (1979), - method FUKIH proposed by AKOSY AT. AL. (2009) and - method of Kille (1970). All methods are simple to perform and not challenging to input data. When comparing methods, the main problem is that, the results obtained by different methods are very different. Another point of this work is to evaluate the concentrations of total phosphorus in the tatal runoff. Here is analyzed series of daily concentrations of total phosphorus and monthly and annual average concentrations. Low and high concentrations are compared with the values ??of precipitation and clinks are searched between these values. The main problem is that, the concentration of phosphorus are not dependent only on precipitation. The last point is solution of influnence of baseflow to the amount of total phosphorus in the runoff. Here is used the procedure which described BYSTŘICKÝ in its work (2012). There are determined values concentrations typical of baseflow, for direct runoff and total runoff. Groups of values ??are mutually tested and compared. The results show that, the baseflow is negligible contributor of phosphorus to the total runoff, but to achieve more accurate results would be needed to analyse a longer time period (eg 10 years) and compare the results with several different river basins.
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