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1362. Titulní list
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Slovak
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1363. Titulní list
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Slovak
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1364. Tlakové proudění mostním otvorem a přelévané mosty
- Creator:
- Picek, Tomáš, Havlík, Aleš, and Mattas, Daniel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bridge opening, overflowed bridge deck, backwater by the bridge, discharge through the opening, mostní otvor, přelévaná mostovka, vzdutí mostem, and výtok otvorem
- Language:
- Slovak
- Description:
- In the paper, authors are concerned with a hydraulic behaviour of bridges at high water stages and especially with the so far almost unregarded case when bridge roadway is overflowing. There are mentioned their own solutions for the estimation of the backwater by the bridge besides assessment of the applicability of some used relations. These new solutions were derived on the basis of research on the physical model at hydraulic laboratory of the Faculty of Civil Engineering of the Czech Technical University in Prague in 2001 and 2002. and Studie se zabývá hydraulickým chováním mostů při vysokých vodních stavech a zejména dosud téměř opomíjeným případem, kdy dochází k přelévání mostovky. Vedle posouzení aplikovatelnosti některých používaných vztahů jsou zde také uvedena vlastní řešení pro stanovení vzdutí mostem. Tato nová řešení byla odvozena na základě výzkumu na fyzikálním modelu prováděného v letech 2001 a 2002 v hydraulické laboratoři Fakulty stavební ČVUT v Praze.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1365. Tolerance of canola to drought and salinity stresses in terms of root water uptake model parameters
- Creator:
- Yanagawa, Aki and Fujimaki, Haruyuki
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- irrigation with saline water, biofuel crops, electrical conductivity, and Feddes’s model
- Language:
- Slovak
- Description:
- Canola (Brassica napus) is cultivated for oil as a biofuel crop. Few quantitative data concerning its tolerance to abiotic stresses has been presented. We evaluated the tolerances of canola to drought and salinity stresses in terms of parameter values in a macroscopic root water uptake model. We conducted an experiment using nine columns with two plants in each: three columns were under drought stresses, another three were under saline stress and others provided potential transpiration. Two soil moisture and salinity probes were inserted into each of the six columns under stress to monitor water content and electrical conductivity. Weight of the columns was manually measured to obtain daily transpiration. Water uptake at each depth and time was calculated by substituting linearly interpolated matric and osmotic potentials into the stress response function. Determined stress response functions indicated that canola is more sensitive to drought compared to Jatropha. While, it was found to be as tolerant as Jatropha to salinity stress in terms of transpiration. Matric potential was more determining than osmotic potential to root water uptake of canola.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1366. Towards periodic and time-referenced flood risk assessment using airborne remote sensing
- Creator:
- Brenner, Claire, Meisch, Claude, Apperl, Benjamin, and Schulz, Karsten
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- flood risk management, damage potential analysis, object-based image analysis, orthophoto analysis, and building detection
- Language:
- Slovak
- Description:
- Flood risk management is founded on the regular assessment of damage potential. A significant parameter for assessing damage potential is the number of at-risk objects. However, data sets on exposure are often incomplete and/or lack time-references. Airborne remote sensing data, such as orthophotos, offers a regularly-updated, time-referenced depiction of land use. As such, remote sensing data compensates for incomplete data sources (such as digital cadastral maps). Orthophotos can even be used to analyze the temporal dynamics of flood damage potential, providing that timereferenced information is available for multiple time points. This paper describes a method for integrating orthophotos into flood risk analyses. In Austria, orthophotos are updated every three years, allowing their integration into cyclical flood risk assessments. The results of a case study presented in this paper demonstrate that orthophotos are most useful where other data sources, such as digital cadastral maps, are incomplete. In such situations, orthophotos lead to a significant increase in estimated damage potential. Orthophoto analysis allows damage potentials to be re-assessed at regular intervals, another major advantage over digital cadastral maps. Orthophoto analysis thus supports the evaluation of flood risk management options.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1367. Transforming hydrographs in the hillslope subsurface
- Creator:
- Šanda, Martin and Císlerová, Milena
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- experimental catchment, hydrological monitoring, subsurface trench, preferential flow, soil moisture, dystric cambisol, crystalline granite bedrock, experimentální povodí, hydrologické monitorování, podpovrchový příkop, preferenční proudění, půdní vlhkost, dystrická kambizem, and krystalické žulové podloží
- Language:
- Slovak
- Description:
- To reveal and evaluate the mechanism of transforming rainfall into runoff in the region, where the subsurface flow plays a dominant role in the runoff formation, a continuous hydrological and climatic data monitoring has been set-up in the experimental catchment Uhlířská (the Jizera Mountains, CR). The soil profile (Dystric Cambisol), formed on the weathered granite bedrock, is shallow and highly heterogeneous. Beside a standard catchment data observation a hillslope transect was instrumented to control the flow dynamics in the soil profile. From three soil horizons, the subsurface outflow is recorded in the subsurface trench. Adjacent to the trench the soil water suction is scanned by triplets of automatic tensiometers. Within the soil profile the unsaturated regime prevails, nevertheless the soil keeps almost saturated. Nearly simultaneous reaction of suction on a rainfall in all soil horizons implies a rapid vertical flow. Local preferential flow paths are conducting infiltrating water at significantly variable rates when saturation is reached. Groundwater table, soil moisture and subsurface runoff measured at the hillslope transect and the total outflow from the catchment, are correlated. The outflow from the catchment is dominantly controlled by soil moisture however the mechanism of its generation is not yet fully understood. and V oblasti s dominantním podpovrchovým odtokem bylo započato s kontinuálním hydrologickým a klimatickým monitoringem s cílem popsat a vyhodnotit transformaci srážky na odtok. Experimentální povodí Uhlířská se nachází v severní části České republiky v Jizerských horách. Půdní profil, klasifikovaný jako dystrická kambizem na zvětralém žulovém podloží, je mělký a velmi heterogenní. Svahový transekt byl vystrojen pro sledování dynamiky podpovrchového odtoku. Ve třech půdních horizontech je monitorován odtok a půdní sací tlak. V půdním profilu převládá nenasycený stav, ačkoliv je půdní vlhkost dlouhodobě blízko nasycení. Rychlé vertikální proudění je indikováno téměř současnou odezvou půdního sacího tlaku na srážku ve všech půdních horizontech. Po dosažení nasycení infiltrující voda protéká preferenčními cestami s výrazně odlišnými lokálními rychlostmi. Závislost hladiny podzemní vody, půdní vlhkosti, podpovrchového odtoku ve svahovém transektu na odtoku z povodí je významná. Odtok vody z povodí, které leží na zvětralém žulovém podloží, je dominantně určován půdní vlhkostí. Přes tato zjištění není mechanismus tvorby odtoku zatím jednoznačně popsatelný.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1368. Translační vlny při stálém přítoku do obdélníkového koryta s velmi nadkritickým prouděním provzdušněné vody
- Creator:
- Kybast, Ivan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- roll-waves, open channel, flow phase, depths, velocities, distances and volume of waves, translační vlny, otevřené koryto, fáze proudění, výšky, rychlosti, and vzdálenosti a objemy vln
- Language:
- Slovak
- Description:
- By an analysis of the Brock’s model tests (Brock, 1969) conditions for forming of roll-waves are determined together with experimental equations of their parameters in relation to the channel inflow wave (Kunštátský, Maleňák, Pejchal, 1967; Kybast, 2002), aeration of flow (Douma, 1943; Haindl, Lískovec, 1973), channel slope and roughness along the whole range of the water flows. Calculations of lower and upper flow roll-waves discharge, depths, velocities, time periods, wave distances and volumes are presented. and Rozborem Brockových modelových zkoušek (Brock, 1969) jsou určeny podmínky tvoření translačních vln a experimentální rovnice jejich parametrů v souvislosti s rázovou vlnou napouštění koryta (Kunštátský, Maleňák, Pejchal, 1967; Kybast, 2002), s provzdušněním proudu (Douma, 1943; Haindl, Lískovec, 1973), sklonem koryta a s jeho drsností v celém rozsahu tohoto proudění vody. Předložen je výpočet dolního proudu a horního proudu s translačními vlnami, jejich průtoků, hloubek a výšek, rychlostí, časových period, vzdáleností a objemů vln.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1369. Transpiration and biomass production of the bioenergy crop Giant Knotweed Igniscum under various supplies of water and nutrients
- Creator:
- Mantovani, Dario, Veste, Maik, Gypser, Stella, Halke, Christian, Koning, Laurie, Freese, Dirk, and Lebzien, Stefan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- water use efficiency, transpiration coefficient, photosynthesis, nitrogen, ecophysiology, Lysimeter, and Fallopia
- Language:
- Slovak
- Description:
- Soil water availability, nutrient supply and climatic conditions are key factors for plant production. For a sustainable integration of bioenergy plants into agricultural systems, detailed studies on their water uses and growth performances are needed. The new bioenergy plant Igniscum Candy is a cultivar of the Sakhalin Knotweed (Fallopia sachalinensis), which is characterized by a high annual biomass production. For the determination of transpiration-yield relations at the whole plant level we used wicked lysimeters at multiple irrigation levels associated with the soil water availability (25, 35, 70, 100%) and nitrogen fertilization (0, 50, 100, 150 kg N ha-1). Leaf transpiration and net photosynthesis were determined with a portable minicuvette system. The maximum mean transpiration rate was 10.6 mmol m-2 s-1 for well-watered plants, while the mean net photosynthesis was 9.1 µmol m-2 s-1. The cumulative transpiration of the plants during the growing seasons varied between 49 l (drought stressed) and 141 l (well-watered) per plant. The calculated transpiration coefficient for Fallopia over all of the treatments applied was 485.6 l kg-1. The transpiration-yield relation of Igniscum is comparable to rye and barley. Its growth performance making Fallopia a potentially good second generation bioenergy crop.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1370. Treated wastewater irrigation effects on soil hydraulic conductivity and aggregate stability of loamy soils in Israel
- Creator:
- Schacht, Karsten and Marschner, Bernd
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- hydraulic conductivity, soil aggregate stability, irrigation, treated wastewater, and Israel
- Language:
- Slovak
- Description:
- The use of treated wastewater (TWW) for agricultural irrigation becomes increasingly important in water stressed regions like the Middle East for substituting fresh water (FW) resources. Due to elevated salt concentrations and organic compounds in TWW this practice has potential adverse effects on soil quality, such as the reduction of hydraulic conductivity (HC) and soil aggregate stability (SAS). To assess the impact of TWW irrigation in comparison to FW irrigation on HC, in-situ infiltration measurements using mini disk infiltrometer were deployed in four different long-term experimental orchard test sites in Israel. Topsoil samples (0-10 cm) were collected for analyzing SAS and determination of selected soil chemical and physical characteristics. The mean HC values decreased at all TWW sites by 42.9% up to 50.8% compared to FW sites. The SAS was 11.3% to 32.4% lower at all TWW sites. Soil electrical conductivity (EC) and exchangeable sodium percentage (ESP) were generally higher at TWW sites. These results indicate the use of TWW for irrigation is a viable, but potentially deleterious option, as it influences soil physical and chemical properties.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public