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302. Dopad globální změny klimatu na povodí Bíliny a průběh zatápění zbytkové jámy Bílina. Část I.. Ovlivnění hydrologického cyklu Bíliny
- Creator:
- Košková, Romana, Buchtele, Josef, and Kos, Zdeněk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- hydrologic models, rainfall-runoff relationships, climate change, climate scenarios, hydrologické modely, srážko-odtokové vztahy, změna klimatu, and klimatické scénáře
- Language:
- Slovak
- Description:
- The goal of this contribution is to assess the impacts of a global climate change on the Bilina basin hydrological regime. First part of the contribution focussed on the assessment of hydrological changes in the catchment and evaluation of flow conditions for the coal pit flooding. The Bilina basin is located in the northern Bohemia region near the Krusne Hory Mts. All the territory is intensively used as a coal mine area. Primarily eight climatic scenarios were selected on the basis of GCM ECHAM4 and HadCM2 to generate affected meteorological conditions. New data series were created - temperatures and precipitation – as the input for a rainfall-runoff model. The SACRAMENTO SAC-SMA model has been chosen as a tool for the rainfall-runoff simulations. A number of problems caused by the heavy influence of human activities appeared during a calibration. The model has been successfully verified and eight affected flow data series have been simulated. The scenarios have been ordered according to their influence on hydrological regime. The simulated flows have been statistically analysed and compared. The results show that significant shift in flow annual distribution could be expected. and Příspěvek se zabývá posouzením dopadu globální změny klimatu na hydrologický režim povodí Bíliny a zatápění zbytkové jámy Bílina. První část článku se zaměřuje na posouzení hydrologických změn povodí Bíliny a stanovení průtokových poměrů pro vlastní řešení zatápění zbytkové jámy za klimatické změny. Povodí je součástí Severočeské hnědouhelné pánve. Pro simulaci ovlivněných klimatických podmínek bylo zvoleno osm klimatických scénářů vytvořených na základě výstupů ze dvou globálních cirkulačních modelů ECHAM4 a HadCM2. Byly generovány nové srážkové a teplotní řady sloužící jako vstupy pro srážkoodtokový model SACRAMENTO SAC-SMA, který byl vybrán pro modelování ovlivněných průtoků. V průběhu kalibrace modelu se objevily nesrovnalosti způsobené silným antropogenním ovlivněním povodí; přesto se model podařilo úspěšně verifikovat a pro všech osm zvolených scénářů simulovat ovlivněné průtokové řady. Dané klimatické scénáře a simulované průtoky jsme podle míry ovlivnění hydrologického cyklu ohodnotili a vzájemně porovnali. Výsledky ukázaly, že je možné očekávat výrazný posun v rozložení dlouhodobých měsíčních odtoků.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
303. Dopad globální změny klimatu na povodí Bíliny a průběh zatápění zbytkové jámy Bílina. Část II.. Varianty zatápění zbytkové jámy
- Creator:
- Košková, Romana, Buchtele, Josef, and Kos, Zdeněk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- water resources management, water demand, climate change, revitalisation, water framework, vodní hospodářství, nároky na vodu, změna klimatu, revitalizace, and vodohospodářská soustava
- Language:
- Slovak
- Description:
- The goal of this contribution is to assess the impacts of global climate change on the Bilina basin hydrological regime and the Bilina mine filling. The second part is focussed on flooding of the coal pit under the conditions affected by global warming. There are two approaches how to achieve the objective. The first method uses water from the Bilina river exclusively. The second one takes into consideration an advantage of the existing water resource system and of large water framework enabling water transfer from the Ohre river to the Bilina river to derive portion of water from the Ohre river. The operating regulations at the Nechranice reservoir had to be adapted to the climate change to improve controlled increase of discharge with regard to the flows transported. A simple water balance model was constructed to simulate a function of the Nechranice reservoir and the coal pit filling. Estimation of the climate change influence on the coal pit filling was performed based on the flooding time changes. The results of flooding simulation show that it is not possible to achieve the coal pit flooding by the Bilina river and it is necessary to transfer water from Ohre river to Bilina river. The climate change could significantly prolong the flooding of the coal pit by about 3 years and the operating regulations at the Nechranice reservoir could be considerably influenced. The impact of climate change could be substantially reduced by an improvement of the controlled increase of discharge by the Nechranice reservoir. and Příspěvek se zabývá posouzením dopadu globální změny klimatu na hydrologický režim povodí Bíliny a zatápění zbytkové jámy Bílina. Druhá část článku se zaměřuje na vlastní zatápění zbytkové jámy za klimatické změny. Vytěžená jáma povrchového lomu může být zatopena dvěma způsoby. První způsob využívá k zatopení jámy pouze vodu z řeky Bíliny, druhý počítá s převáděním vody z řeky Ohře do Bíliny pomocí existující vodohospodářské soustavy. Vzhledem ke změněným hydrologickým podmínkám bylo nezbytné přizpůsobit manipulace na nádrži Nechranice na řece Ohři klimatické změně tak, aby bylo možné zabezpečit požadovaný nadlepšený odtok v odběrném profilu čerpací stanice ke krytí požadavků na velikost plnicího přítoku zbytkové jámy Bílina. K tomuto účelu byl vytvořen jednoduchý bilanční model funkce nádrže Nechranice zohledňující různé velikosti převáděných objemů vody. Posouzení vlivu klimatické změny na zatápění zbytkové jámy proběhlo na základě rozboru délky plnění jámy. Simulace plnění zbytkové jámy ukázaly, že jámu nelze zatopit v doporučené době a bude proto nezbytné realizovat převody vody z Ohře do Bíliny. Klimatická změna patrně podstatně prodlouží dobu zatápění jámy zhruba o 3 roky a také výrazně zasáhne do manipulací na nádrži Nechranice. Nádrž Nechranice může podstatně zmírnit dopad klimatické změny úpravami velikostí nadlepšených odtoků.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
304. Doplnky k slovenskému frazeologickému slovníku
- Creator:
- Tvrdý, Peter
- Publisher:
- nákladom Československej grafickej Unie
- Format:
- print, svazek, and 240 stran.
- Type:
- model:monograph and TEXT
- Subject:
- Západoslovanské jazyky, slovenština, frazeologie, Slovak language, phraseology, 811.162.4, 81'373.7, (038)81, 11, and 811.162
- Language:
- Slovak
- Description:
- sostavil Peter Tvrdý.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
305. Dr. Boris Sevruk is seventy
- Creator:
- Szolgay, Ján
- 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
306. Drag reduction of dense fine-grained slurries
- Creator:
- Vlasák, Pavel, Chára, Zdeněk, and Štern, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- kaolin slurry, drag reduction, experimental investigation, peptization, slurry rheology, kaolinové suspenze, snižování tření, experimentální výzkum, peptizace, and reologie suspenzí
- Language:
- Slovak
- Description:
- Attractive and repulsive forces acting in the slurry due to different ions absorbed on surface of fine particles, especially colloidal ones, strongly affect the flow behaviour of highly concentrated fine-grained slurries. The attractive forces between the fine-grained solid particles initiate the coagulation process, which gives rise to voluminous aggregates where a large amount of water is fixed. A modification of the physicalchemical environment of the slurry by addition of a peptizing agent produces repulsive forces between particles. They result in destruction of the aggregates, water originally fixed in the aggregates is liberated, the viscous friction can play a larger role in the slurry, which is liquefied. To prove these process three different kaolin-water mixtures were tested with an overpressure capillary viscometer, rotational viscometer, and experimental pipeline loop. The effect of two peptizing agents and their concentration was investigated. It was demonstrated that even very low concentration of peptizing agent results in a significant reduction in the apparent viscosity and in the yield stress. and Přitažlivé a odpudivé síly působící mezi částicemi v suspenzi v důsledku různých iontů absorbovaných povrchem jemných, zejména koloidních částic, silně ovlivňují tokové chování vysoce koncentrovaných jemnozrnných suspenzí. Přitažlivé síly mezi jemnými částicemi iniciují proces koagulace, umožňují vznik objemných agregátů, v nichž je vázáno značné množství vody. Změna fyzikálně-chemického prostředí suspenze přidáním peptizačního činidla podpoří vznik odpudivých sil mezi částicemi, které způsobí rozbití objemných agregátů a voda vázaná v agregátech se uvolní, vazké tření tak bude hrát v suspenzi významnější roli a dojde k ztekucení suspenze. Tento proces byl ověřen experimentálním výzkumem třech různých kaolinových suspenzí jednak na kapilárním přetlakovém viskozimetru, na rotačním viskozimetru a na experimentální potrubní trase. Byl ověřen účinek dvou peptizačních činidel a bylo ukázáno, že velmi nízká koncentrace peptizačního činidla vede k významné redukci zdánlivé viskozity a počátečního napětí.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
307. Droplet infiltration dynamics and soil wettability related to soil organic matter of soil aggregate coatings and interiors
- Creator:
- Fér, Miroslav, Leue, Martin, Kodešová, Radka, Gerke, Horst H., and Ellerbrock, Ruth H.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- aggregates, clay and organic matter coatings, WDPT, contact angle, and DRIFT spectroscopy
- Language:
- Slovak
- Description:
- The organo-mineral coatings of soil aggregates, cracks, and biopores control sorption and macropore-matrix exchange during preferential flow, in particular in the clay-illuvial Bt-horizon of Luvisols. The soil organic matter (SOM) composition has been hypothesized to explain temporal changes in the hydraulic properties of aggregate surfaces. The objective of this research was to find relations between the temporal change in wettability, in terms of droplet infiltration dynamics, and the SOM composition of coated and uncoated aggregate surfaces. We used 20 to 40 mm sized soil aggregates from the Bt2 horizon of a Haplic Luvisol from loess that were (i) coated, (ii) not coated (both intact), and (iii) aggregates from which coatings were removed (cut). The SOM composition of the aggregate surfaces was characterized by infrared spectroscopy in the diffuse reflection mode (DRIFT). A potential wettability index (PWI) was calculated from the ratio of hydrophobic and hydrophilic functional groups in SOM. The water drop penetration times (WDPT) and contact angles (CA) during droplet infiltration experiments were determined on dry and moist aggregate samples of the three types. The decrease in the CA with time was described using the power function (CA(t) = at–b). For dry aggregates, the WDPT values were larger for coated as compared to uncoated regions on the aggregate surfaces, and increased with increasing PWI value (R2 = 0.75). The a parameter was significantly related to the WDPT (R2 = 0.84) and to the PWI (R2 = 0.64). The relations between the b parameter and the WDPT (R2 = 0.61) and the PWI (R2 = 0.53) were also significant. The WDPT values of wet soil aggregates were higher than those of dry aggregates due to high water contents, which limited the droplet infiltration potential. At the wet aggregate surfaces, the WDPT values increased with the PWI of the SOM (R2 = 0.64). In contrast to dry samples, no significant relationships were found between parameters a or b of CA(t) and WDPT or PWI for wet aggregate surfaces. The results suggest that the effect of the SOM composition of coatings on surface wettability decreases with increasing soil moisture. In addition to the dominant impact of SOM, the wettability of aggregate surfaces could be affected by different mineralogical compositions of clay in coatings and interiors of aggregates. Particularly, wettability of coatings could be decreased by illite which was the dominant clay type in coatings. However, the influence of different clay mineral fractions on surface wettability was not due to small number of measurements (2 and 1 samples from coatings and interiors, respectively) quantified.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
308. Drought impact on ground beetle assemblages (Coleoptera, Carabidae) in Norway spruce forests with different management after windstorm damage – a case study from Tatra Mts. (Slovakia)
- Creator:
- Šustek, Zbyšek, Vido, Jaroslav, Škvareninová, Jana, Škvarenina, Jaroslav, and Šurda, Peter
- Type:
- article, model:article, and TEXT
- Subject:
- drought, ground beetle, windstorm, forest management, and Norway spruce
- Language:
- Slovak
- Description:
- After the windstorm of November 2004, the ground beetle assemblages (Coleoptera, Carabidae) differentiated after the windstorm into four groups reflecting degree of damaging and forestry management (intact stand, fallen timber in situ, extracted timber, fire). The stand with fallen timber reduced abundances of original species. Removal of timber eliminated sensitive forest species and favored tolerant species, whereas the fire allowed invasions of field species. Later, the assemblages on burned sites converged to those in the unburned sites. Their restoration has a sigmoid-like course. Independently on the above differentiation and course assemblage succession, episodes of severe drought resulted with a 1–2-years delay in sudden decline of number of individuals and species. Their numbers were restoring after longer humid periods. Because these extremes occur with a considerable regularity, the observed extremes of fluctuations of number of species and individuals represent the variability limits of the Carabid assemblages in such conditions. The Standardized Precipitation Evapotranspiration Index was shown, using the cross-correlation of SPEI and number of individuals and species of Carabids, as a suitable means to explain and predict such changes for the period of 1–2 years.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
309. Dynamics of organic carbon losses by water erosion after biocrust removal
- Creator:
- Cantón, Yolanda, Román, Jose Raúl, Chamizo, Sonia, Rodríguez-Caballero, Emilio, and Moro, María José
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- biological soil crust, dissolved OC, sediment OC, runoff, biocrust disturbance, and physical crust
- Language:
- Slovak
- Description:
- In arid and semiarid ecosystems, plant interspaces are frequently covered by communities of cyanobacteria, algae, lichens and mosses, known as biocrusts. These crusts often act as runoff sources and are involved in soil stabilization and fertility, as they prevent erosion by water and wind, fix atmospheric C and N and contribute large amounts of C to soil. Their contribution to the C balance as photosynthetically active surfaces in arid and semiarid regions is receiving growing attention. However, very few studies have explicitly evaluated their contribution to organic carbon (OC) lost from runoff and erosion, which is necessary to ascertain the role of biocrusts in the ecosystem C balance. Furthermore, biocrusts are not resilient to physical disturbances, which generally cause the loss of the biocrust and thus, an increase in runoff and erosion, dust emissions, and sediment and nutrient losses. The aim of this study was to find out the influence of biocrusts and their removal on dissolved and sediment organic carbon losses. One-hour extreme rainfall simulations (50 mm h-1) were performed on small plots set up on physical soil crusts and three types of biocrusts, representing a development gradient, and also on plots where these crusts were removed from. Runoff and erosion rates, dissolved organic carbon (DOC) and organic carbon bonded to sediments (SdOC) were measured during the simulated rain. Our results showed different SdOC and DOC for the different biocrusts and also that the presence of biocrusts substantially decreased total organic carbon (TOC) (average 1.80±1.86 g m-2) compared to physical soil crusts (7.83±3.27 g m-2). Within biocrusts, TOC losses decreased as biocrusts developed, and erosion rates were lower. Thus, erosion drove TOC losses while no significant direct relationships were found between TOC losses and runoff. In both physical crusts and biocrusts, DOC and SdOC concentrations were higher during the first minutes after runoff began and decreased over time as nutrient-enriched fine particles were washed away by runoff water. Crust removal caused a strong increase in water erosion and TOC losses. The strongest impacts on TOC losses after crust removal occurred on the lichen plots, due to the increased erosion when they were removed. DOC concentration was higher in biocrust-removed soils than in intact biocrusts, probably because OC is more strongly retained by BSC structures, but easily blown away in soils devoid of them. However, SdOC concentration was higher in intact than removed biocrusts associated with greater OC content in the top crust than in the soil once the crust is scraped off. and Consequently, the loss of biocrusts leads to OC impoverishment of nutrient-limited interplant spaces in arid and semiarid areas and the reduction of soil OC heterogeneity, essential for vegetation productivity and functioning of this type of ecosystems.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
310. E-psychologie: elektronický časopis ČMPS
- Type:
- issue, normal, model:periodicalitem, and TEXT
- Language:
- Czech, English, and Slovak
- Description:
- 2
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public