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Dynamika půdní vody na Šumavě a v Krkonoších v srpnu 2002
Tesař, Miroslav ; Krejča, M. ; Polívka, Jiří ; Šír, Miloslav
The soil water movement during extreme rain is analysed in the Doupě and Kout catchment (Šumava Mts, Southern Bohemia) and in the Modrý Důl catchment (Krkonoše Mts., Northern Bohemia). Two cyclones, which moved from Hungary to Poland, caused extreme rainfall and subsequent extreme runoff in August, 2002. Precipitation, air and soil temperature, and tensiometric pressure were recorded in catchments. The analysis showed that the huge rain amount in August 2002 exceeded the retention capacity of the catchment covered by mature spruce forest and dwarf pine forest (Modrý Důl), dead forest and herb undergrowth (Kout), clearing covered by herbs (Doupě). It means that the plant cover played a negligible role in the runoff generation. The soil cover was not able to prevent the country from catastrophic runoff because its retention capacity is rather low (60 – 90 mm).
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Mikroskopická variabilita hydraulických vlastností půdy v borovicovém lese u obce Sekule na jihozápadě Slovenska
Orfánus, T. ; Lichner, Ľ. ; Šír, Miloslav ; Tesař, Miroslav
The variability of water repellency of pine-forest arenic Regosols and its influence on the infiltration process were estimated at the locality of Mláky II near Sekule in south-west Slovakia. The water drop penetration time (WDPT) tests of soil water repellency and infiltration tests with a miniaturized tension infiltrometer (3 mm diameter) at single-sample scale (100 cm3 volume, 22 cm2 surface) were performed. Extreme heterogeneity of water repellency and infiltration velocity was recorded. All the results suggested that the hydraulic properties of the soil are changing at millimetre scale due to the presence of unevenly distributed hydrophobic material.
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Formování odtoku v revitalizované podhorské pramenné oblasti v Senotíně
Tesař, Miroslav ; Syrovátka, O. ; Lichner, Ľ.
The purpose of the Senotín pilot project (1993–2000) was to determine methods of revitalisation of a sub-mountain headwater area (0.38 km2) in the Novobystřická Vysočina Highlands (610–725 m a. s. l.). Seven underground clay shields stopped pipe drainage, and four balks prevented surface and subsurface runoff. These adaptations improved the water retention capacity of the whole catchment, as demonstrated by the formation of runoff in the revitalised area. A typical rainstorm (amount 15 mm, duration 5.6 hours, max. intensity 1.8 mm/20 minutes) and consequent runoff was analysed, along with the role of soil in runoff retardation and water retention. The time course of the contributing area was also quantified. The contributing area was formed in the surface soil layer with a thickness of about 40 cm. Runoff retardation lasted two hours after the rain began. Retention reached 98% of the total rainfall. Runoff lasted for 85 hours.
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Variability of water regime in forested experimental basis
Buchtele, Josef ; Tesař, Miroslav
Climatic conditions represent a significant factor for water regime of a watershed. They form conditions both for the vegetation cover development in the annual cycle and also its changes in the span of decades of years. Land-use changes can be a reason of variability and/or tendencies in the evapotranspiration process affecting water balance in both short-term and long-term temporal scales. The present contribution deals with simulations of the rainfall-runoff process with the help of SAC-SMA (Sacramento Soil Moisture Accounting) a BROOK´90 models. The time course of differences between observed and simulated runoff represents a possible tool for the evaluation of tendency and/or variability of water regime of a basin. The used approach makes possible to assess a result of long-term development of the vegetation cover in a catchment and consequent evapotranspiration changes.
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Vliv vegetace na tepelnou bilanci a výměnu entropie
Šír, Miloslav ; Weger, J. ; Tesař, Miroslav ; Lichner, Ľ.
The aim of this study is to quantify the synergy between the vegetation cover, solar radiation, air temperature and soil moisture. Heat balance, potential and actual transpiration, and net entropy exchange at three localities under different plant cover was studied in order to determine crucial factors determining phytomass productivity in cold climatic areas of Bohemian Forest. The phytomass productivity can be quantified by the entropy exchange associated with the latent heat flux. Water shortage is a crucial factor determining phytomass productivity in dry and warm seasons in cold climatic conditions of Czech mountains.
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Wind drifted snow influence on the water balance in the catchment “Modrý potok”, the Giant Mountains, Czech Republic
Dvořák, I.J. ; Tesař, Miroslav ; Harčarik, J.
There are very specific components of the water balance in the mountain headwater regions. Beside the point of cloud- and fog-water deposition it is mainly accumulation of water in the snow cover drifted in the watershed by the wind. To get more realistic data, two digital models using cinematic carrier phase-based GPS measurements were developed: a model for snow surface data and the one for the underlying snow free ground surface. These two models have identified snow depths. The objective of this study is to highlight water storage in the snow-beds and show the GPS cinematic measurements as a contribution to best insight the snow accumulating and melting processes in the Modrý potok basin in the Giant Mts.
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The solid depozited precipitation in the small catchments in the Czech Republic
Fišák, Jaroslav ; Tesař, Miroslav
The samples were collected in two localities differing in the industrial pollutant load. The first locality situated in the Sumava Mts. represents a relatively clean region of the Czech Republic. The second locality is situated in the Northern Bohemia. This locality is represented by the Milesovka Observatory of the IAP ASCR. The region is heavy polluted by the industrial load in this case. The one-shot sample collection in the Sumava Mts. at 28 localities was made on January 4th, 1990. There were shown: i) The ion concentrations in the rime water depend on the industrial load of the region and on the local pollutant sources; ii) The local pollutant sources play the main role in ion concentrations in rime water; iii) The ion concentrations decrease with altitude.
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