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The change of the rain factor on the net of stations in the Czech Republic during 1961-2010
Střeštík, Jaroslav ; Rožnovský, J. ; Štěpánek, P. ; Zahradníček, P.
Precipitation totals do not express precisely the humidity conditions in the landscape. Therefore the Lang’s rain factor, constructed from monthly and annual average temperatures and precipitation totals on 267 stations in the Czech Republic during 1961-2010, has been used here. Its values are very different at different stations, the lowest they are at South Moravia and Labe lowlands. Its average for the whole territory displays a slow decrease during the 50 years, supplemented by strong fluctuations. The strongest decrease appears in the Northern boundary mountains. The same factor calculated only for summer displays stronger differences between highlands and lowlands, especially in South Moravian ones. Stronger decrease at North Moravia, especially in mountains, and very weak decrease at other parts takes place.
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Influence of water regime on growth and quality of selected grass species
BÁRTA, Ondřej
This thesis describes the importance and use of permanent grasslands, or more so-called energy grasses used in the energy sector. For our study we examined these three grasses: Ovsík vyvýšený (Arrhenatherum elatius), Sveřep horský (Bromus carharticus) and Bojínek luční (Phleum pratense). Another, the main task was to determine their resistance to drought. The results based on laboratory work, which between them compared the two variants. One was simulated normal emergence of the species and the second emergence stressed by lack of water. Based on these results, we conclude that we can not say that it would be a downright drought-resistant types. For the two studied species of grasses (Bojínek and Ovsík) are obvious differences in resistance to drought. Sveřep horský (variety - Tacit), however, proved to be the most drought-resistant species. While most sprouted out bojínek luční (variety - Sobol).
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Character of precipitation during the last 200 years in Prague Klementinum and their impact on water management in the landscape
Střeštík, Jaroslav
The course of the annual precipitation displays no change over 200 years, only a very slow decline during the 20th century, particularly in its second half. The same, just a little stronger trend holds true for the number of days in each year with abundant precipitation and for percentage of annual precipitation in these days. Therefore, more and more water falls during weak rains instead of the richer ones, which is not favorable for agriculture, because more water evaporates shortly after the rain. In the same period, water flows in major rivers increase, or very little decrease, although precipitation totals are falling more rapidly. Therefore, the proportion of water flowing into the sea is increasing and the proportion remaining in the landscape decreases. All these factors contribute to an intermittent water shortages and an increasing risk of drought occurrence.
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Method of testing of the seed traits and seedling development under abiotic stress conditions for selection of oilseed rape genetic resources
Bláha, Ladislav ; Vyvadilová, Miroslava
The method is based on laboratory tests of speed of seed germination, emergence and seedling growth under different stress conditions simulated by subnormal water level, extreme high and low temperatures. It allows to eliminate already at the seed level the plant materials (initial breeding materials and cultivars) which do not tolerate extreme temperatures and temperature changes during germination, have a low water use efficiency and are intolerant to abiotic stresors. It was confirmed that these genotypes have also poor field emergence and initial growth of roots with implications for further vegetation period, mainly for over wintering and spring regeneration what has significant influence on the yield. The method represents the tool for screening of genetic resources with the resistance to the abiotic stresors and this technology process is acceptable also for other crops.
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Influence of water regime on growth and quality of selected grass species
STEJSKAL, Jan
This thesis deals with permanent grassland, their meaning and use. The thesis is focused on the influence of water regime on selected grass species Kentucky bluegrass (Poa pratense) and Creeping thin (Agrostits tenuis), its resistance to drought, water stress and the impact of growth and production in the absence of water. The work was carried out under laboratory conditions and areas where attempts have been made regarding the germination of grasses in the absence of water. A sub-task was to evaluate dry matter yield for grass species.
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A usability of remote sensing for evaluation of economic impact of drought
FRANKOVÁ, Lenka
Drought is a natural phenomenon which has got an important influence on human economic activity and other areas of human life. This work, based on literary sources, summarizes current available information about the issue of drought. The work is primarily focused on agricultural problems with drought in the Czech republic but summarizes even the ohter problems of drought, for example sociological impacts. There is also a perspective given to the generally used methods for studying and evaluation of drought. Considering the relation of drought to water stress of plants and vegetative covering the problems are also summarized. Besides the evaluation of drought and related problems, the work deals with the question of the possibility of usage of technology for remonte sensing the Earth in evaluation of drought and water stress of vegetative covering which may be the indicator of the drought. There are discussed possibilities of usage optical and thermal methods. The problem of drought is duscussed in broad context of ecological function of the landscape. Potencial human influence on drought is duscussed.
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Comparison of drought and frost resistence of selected varieties of \kur{Medicago sativa} L. from domestic and foreign breeding
HLAVÁČKOVÁ, Petra
The aim was comparison of drought and frost resistence of selected varieties of Medicago sativa L. from domestic and foreign. The evaluation was performed by a series of laboratory experiments and observations in two replications in 2009 ? 2010. The results were evaluated as the most resistant varieties to frost variety from the Czech Republic and Slovakia. Namely variety Magda Litava, Tisa and Synthesis. As the least resistant varieties have been evaluated varieties from the warm coastal areas. Most resistant varieties to water deficit during vegetation varieties were evaluated Magda, Comete, Europe and Camilla. The climatic conditions of the Czech Republic would be most appropriate, according to the results observed varieties of Magda. It has high resistance to frost and has good results in drought. Other good varieties from Czech Republic are Pálava and Camilla. Of the foreign varieties would be best to use a French variety of Como, Europe and the Dutch variety of Capri. These varieties have good resistance to frost and high drought. The whole problem of drought and frost resistance of alfalfa is not yet explored, it would be appropriate, the results obtained confirmed by further research.
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Hydrometeorological droughts in the Czech territory since 1851
Kakos, Vilibald ; Müller, Miloslav
Variously long periods of precipitation deficit were studied. In the 20th century, the most intensive drought period was first half of 30s. Nevertheless, the drought in first half of 60s of the 19th century was even stronger from the viewpoint of precipitation as well as outflow characteristics. Hydrological droughts arise generally later than precipitation deficits as was shown by comparison of both types of droughts.
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