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Růst dřevin a jejich okus zvěří při různých způsobech přípravy plochy a různém ošetření proti buřeni v lokalitě Les Království
Provazníková, Pavla
The aim of this bachelor work was to evaluate the influence of various surface preparation and the effect of various ways of treating forest plantation against forest weeds on the subsequent growth and browsing by wild game. The work was implemented at Lesy ČR s.p. (Forests of the Czech Republic), in the forest range Království. Two experimental plots were marked off in selected localities. In one plot there were crushed wood chips left on the ground, in the other there were branches thrown into piles. The browsing of trees took place at 9 experimental plots and 2 transects. The smallest overall height in 2014 was evident on young plants on the plot with wood chips -- 53.8 cm. The highest growth for the year 2014 was detected on the areas with individual trimming -- 7.8 cm. The most damage by game was monitored on the plot with an area--wide herbicide application, where a total of 31 % young plants were damaged, the least damaged seemed to be the wood chipped area with a total damage of 7%. The browsing of trees in the spruce only transect resulted in 5.4 %. The spruce--beech transect was damaged by 28.6 %, with the common beech being damaged by browsing on 78 % of specimens, browsing damage was not detected on Norway spruce.
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Microclimate and energy balance characteristics of the stands with different management
ERBEN, Jiří
The present thesis deals with the microclimate and energy balance indicators of 2 habitats with different types of vegetation (wetland, pasture) during the growing season. Mainly moisture and temperature regime and energy fluxes were monitored in the period of 1.4. to 30.9., 2014. All values were dependent on the type of vegetation, and the type and location of the environment. Microclimate analysis was performed on two locations - in a pasture in the basin of Mlýnský stream and wetland habitat in the basin of Horský stream. Both sites are located on the right bank of the Lipno lake. All the necessary meteorological characteristics were measured using automatic weather stations. Indicators of temperatures and humidity of soil and air, received, and the total amount of reflected sunlight and heat balance characteristics - albedo, Bowen ratio, evaporative fraction and heat flows were evaluated. The biggest differences were monitored at heights, in which was measured. In terms of relative humidity, values most varied at canopy level, where the differences were noticeable. The highest mean relative humidity was measured at height of 0.2 m and 2 m on the wetland. As relative humidity even air temperature is dependent on the height at which it was measured. While the height of 2 m, the values at both sites was almost identical, at the canopy level are differences significant. The average temperature values depend on the season, but the largest amplitude of the temperature reached the sites in June. The surface temperature of the soil at the wetland was almost unchanged, contrary to pasture its course was similar to air temperatures series at the canopy level. The soil temperature at 20 cm was almost the same at both sites. In terms of energy fluxes, it was found that the highest latent heat flux of evaporation was in wetland. Sensible heat flux was higher in the pasture. The flux of heat into the ground is bigger during the morning and evening hours on the wetland, however ground heat flux was higher in the pasture during the day.
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Výroba a vlastnosti vrtáků
Kukla, Jan
The bachelor work is based on a survey of the production and basic characteristic of the production and properties of drills in the company, which deals with the total production of drilling tools. Five-axis CNC tool grinders are able to achieve high precision processing with a wide range of different types of materials. Hardness, toughness and heat resistance of drill bits are specified prefabricated bore material (aluminium, stainless steel, etc.), the geometry of a cutting edge drills (Mitsubishi, Gühring, "RDS", etc.) and the type of the coating (TiAlN, AlCrN, ArTiN, CC Alu speed, etc.), or processing of the surface (nitriding, blackening).
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Použití sladových výtažků do perníkových těst
Pohlodková, Lenka
Topic of my diploma thesis is "Using of malt extracts for gingerbread doughs". The subject of this thesis is possibility of use baking malt extract for gingerbread doughs. In this examination, six kind of gingerbread was made. The difference in the compound of the examined gingerbreads was use of various kinds of sweeteners. For this examination were used honey, invert sugar and malt extract. For the other gingerbread doughs were used these combinations of sweeteners (invert sugar + honey, invert sugar + malt extract and honey + malt extract). For this sensory analysis were used eight descriptors -- shape, colour, surface, smell, porosity, aroma of spices, overall flavour and overall impression. Besides the sensory analysis, also was measured colour of gingerbreads with using spectrophotometer. By the sensory analysis and spectrophotometric determinativ was found, that the darkest gingerbreads were with invert sugar in combination with honey and the lightnest gingerbreads were with malt extract and with honey. From the results of this sensory analysis was defined that, the sample where invert sugar was used, gave best results. The use of malt extract for gingerbread dough is not suitable, mainly because of the bad colour, smell and flavour of the final product. There is possibility to use malt extract in combination with invert sugar for better characteristics of the final product. In this case, the invert sugar will be the predominate sweetener (malt extract in amount of 2 %).
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Vliv triazinových pesticidů na ryby
STARÁ, Alžběta
Fish and crayfish are widely used as biological monitors of environmental levels of anthropogenic pollutants. The present thesis is a contribution to the assessment of the toxicity and effects of long-term effect of triazines on the different developmental stages of common carp (Cyprinus carpio L.) and adult red swamp crayfish (Procambarus clarkii). The carp was selected as a model fish due to its economic importance, e.g. carp farming contributes about 90% to total fish production in the Czech Republic. Crayfish are easily identified species representing given locality, they are widespread, and they provide a sufficient amount of tissue for individual biochemical and chemical analyses. The results of these studies provide further data on chronic exposure to triazines for consideration in risk assessment. We selected three active substances of triazine herbicides which are the most frequently detected in surface waters such as prometryne, simazine and terbutryn. The findings contribute to knowledge of the toxic potential of triazine herbicides to carp and crayfish at environmentally relevant concentrations in Czech rivers. There is a scarcity of information regarding the toxicity of triazines on freshwater organisms. During the tests we monitored several parameters: behaviour, mortality, biometric, haematological, biochemical blood, histopathology, oxidative stress and antioxidants. The data obtained from all tests performed during my thesis are very valuable for assessment and evaluation of long-term effects xenobiotics on aquatic organisms, especially fish and crayfish. In the future, I would extend the focus of my research for study of possible synergic or amplifying effect of mixtures triazines with other xenobiotics which are often found in the aquatic environment. This approach is recently accented as the aquatic environment is polluted by mixtures of different compounds. Therefore, more research is needed in order to clarify the more detailed effects of xenobiotics on non-target aquatic organisms.
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Ecological consequences connected with sealing of soils in Prague periphery influenced by higway D1
Polická, Petra ; Šefrna, Luděk (advisor) ; Bláhová, Štěpánka (referee)
Sealing of soils in the city fringe is currently reaching a range, which we have never seen in the past. Cities are spreading, commercial development along important highways is rising and hectares of the fertile soils are diseppearing under the tons of concrete, asphalt and other artificial surfaces. The negative consequences of the loss of this important nature resource on the environment and lanscape balance are obvious. Impervious surfaces are the main reason of the run off changes, of the changes in the matter exchange between ekosystems and of the loss of a lot of important soil functions. The landscape is being homogenized and its fragmentation is rising. This work warns against irresponsible sealing of fertile agricultural soils surroundings the highway D1 in the periphery of Prague. Two thirds of sealed soils belong to the first classes of soil protection (luvisols), which can be built up only exceptionally. Contemporary legislative in the Czech Republic is visibly poor and it is necessary to accept more efficient control instruments. Keywords: Suburbanization, Sealing of soils, Impervious surfaces, Soil functions
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Distribution, binding and mobility of Ni in soil in the closed Ni mining area in the vicinity of Křemže
Pipková, Zuzana ; Ettler, Vojtěch (advisor) ; Vaněk, Aleš (referee)
Soils in the vicinity of Křemže in the Southern Bohemia are developed on altered ultrabasic rocks. The occurrence of Ni-hydrosilicate and Fe-rich ores in this area lead to their mining mainly during 19th century, then during the World War II. This thesis is focused on distribution and availability of Ni, Cr and Co and accompanying elements in soils at former mine and prospection sites (2 soil profiles and 32 topsoil samples at historical surface mine area). In all soil samples, physico-chemical parameters (pH, TOC, TS) and bulk concentrations of Al, Ca, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn were measured. In addition, deionised water, DTPA and EDTA extracts were used to determine the (bio)availability and mobility of these elements. Some of trace elements were found in elevated concentrations in the mining area topsoils; mean Ni: 1175 mg/kg (range 545-2849 mg/kg), mean Cr: 416 mg/kg (240-849 mg/kg), mean Co: 127 mg/kg (65-238 mg/kg), mean Fe: 49155 mg/kg (30460-113800 mg/kg), mean Mg: 12648 mg/kg (8795-18770 mg/kg) and mean Mn: 1480 mg/kg (1028-2319 mg/kg). In soil profiles the Ni availability decreased with depth. In the uppermost organic O horizon in forest soil profile, 19.5 % and 23.8 % of total Ni was extracted by DTPA and EDTA, respectively. The extractabilities are decreasing down to mineral...
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Medieval non-ferrous metallurgy. Contribution to an interpretation of findings on Republic square in Prague
Vyšohlíd, Martin ; Sláma, Jiří (referee) ; Klápště, Jan (advisor)
The intention of this work's author was an interpretation of two almost identical items (pits) found during an extensive archeological research in the area of the former barracks Jiřího z Poděbrad, náměstí Republiky, Prague New Town. Items distant from each other 50 meters were unearthed within one year between 2004 and 2005. The items were represented by the pits sunk in the subsoil oriented west-east. A construction fragments were found on their bottoms. The first of the items was to a large degree disturbed with interferences in the 17th century. Only one half of it has remained until today. The other item, unearthed in the náměstí Republiky area (nearly next to the st. Joseph church entrance) was not destroyed by younger interferences. This was a linear pit 4,4 meters long, maximum width 1,8 meters (in the central part), 1,2 meters deep. There was a heating channel in its center made of two lines of diabase rocks (0,63 - 1,35 meters long). These rocks were commonly used in the fire using items the middle ages in the Prague area because of their heat accumulation capacity. Joints between individual rocks as well as their surface areas were filled with fired clay (puddle). On top of this construction a clay ring was placed (5-20cm wide; 0,65-0,85 inner diameter). Both items were filled with mostly with...
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Optimalizace podmínek hydratace v ESEM
Autrata, Rudolf ; Neděla, Vilém
Study of biological specimens of soft tissues with fine and very fine hydrated structure still remains a big problem because this structure can be easily damaged by dehydration during the initiating phase of vacuum pumping of a microscope. The attention is thus focused on setting up the conditions for complete dehydration of samples, ensuring the nature state of a sample during the critical phase of pumping of a microscope
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