|
|
Jak anatomické a ekofyziologické charakteristiky podrostních bylin temperátních doubrav souvisí s jejich reakcí na sucho
Joura, Libor
Trees modify the environmental conditions for the growth of the shrub and herb layer. Nowadays, the tree layer in forest stands is changing at an unprecedented speed due to the influence of management and the influence of increasing natural mortality. Dense forest stands are considered a refuge for herbs from increased temperature due to global climate change. On the other hand, the surface temperature of leaves in thinned forest stands is indeed higher, but it also gives the possibility of active defense against drought or pathogens. In the diploma thesis, the effect of drought stress and lack of sunlight on anatomical parameters and their correlation with physiology was investigated in selected species of understory herbs growing in temperate oak forests, specifically in the Asarum europaeum L. and Hepatica nobilis Schreb. As a result of drought stress, Asarum europaeum experienced changes in the size of the xylem area of the petiole and the total area of the lumen of the petiole vessels. Furthermore, in the size of the surface area of the vessel lumen, which also changed due to the lack of sunlight. Drought stress had a significant effect on the size of the leaf area in the Asarum europaeum. In the Hepatica nobilis, drought stress had an effect mainly on the diameter of the lumen of the vessels, where stressed plants had a larger diameter of the lumen of the vessels. Drought stress also had a significant effect on the number of vessels in both species. The effect of drought and lack of sunlight had no significant effect on the observed correlations between anatomical and ecophysiological parameters. The Asarum europaeum approaches an isohydric survival strategy. It has a higher degree of stomatal regulation, forms a more efficient but sparser xylem due to a higher diameter of the lumen of the vessels and a larger area of the xylem of the petiole. Hepatica nobilis also forms a large vessel lumen diameter, but the xylem is characterized by lower hydraulic conductivity. It therefore forms a safer and denser xylem, corresponding to an anisohydric strategy. The herbaceous layer carries considerable ecological importance for the structure and function of forest ecosystems. It would be beneficial to perceive the herbaceous and tree layer as a more connected and compact unit. Forest management should consider the importance of the herb layer and also its demands in terms of light and water availability. Trees will thus benefit from the contribution of herbs from the point of view of better nutrient dynamics, the ability to moderate soil erosion or from improving the flow of water through the forest floor.
|
|
|
Macrophytes of fishponds in agricultural landscape of selected part of Novohradské hory foothills
SOUKUP, Tomáš
Cílem terénní diplomové práce bylo určování a posouzení diverzity vodních a mokřadních druhů rostlin (makrofyt) v 46 sledovaných vodních nádržích v povodí řeky Vltavy a Malše. Vlastní botanický průzkum probíhal v podhůří Novohradských hor a zaobíral se druhovou identifikací vyšších rostlin ve vymezeném území vodních nádrží, pro které byla současně stanovena i listová pokryvnost dle Braun-Blanquetovy stupnice modifikace Westhoff & van der Makrel. Sběr druhových dat a definování listové plochy probíhalo vždy jen na úrovni vodního ekosystému s členěním na jednotlivé polygony (litorály) s charakteristickými stanovištními společenstvy. Získaná data se následně vizualizovala v mapách a tabulkách druhového zastoupení s přidělenou pokryvností. Z environmentálních ukazatelů se hodnotil obsah dodatkových živin v nádrži, velikost rybí obsádky, chov kachen, charakter a mocnost sedimentů, vodní stav, převažující zemědělské využití půdy v blízkém okolí, rozloha vodní plochy a hlavní spádové povodí dané oblasti. Zmíněné ukazatele (podmínky) se zaznamenávaly pro každou vodní nádrž a staly se podkladem pro další statistické hodnocení mokřadního ekosystému. Diplomová práce se skládá ze dvou částí - rešeršního zpracování problematiky rybničního hospodaření s dopady na doprovodnou vodní vegetaci a statistického vyhodnocení identifikovaných údajů. Ze sumarizovaných statistických dat vzešla skutečnost zvýšené diverzity druhů v povodí řeky Vltavy u částečně letněných rybochovných nádrží. Mapování a sběr botanických vzorků proběhl ve vegetační sezóně 2015, v období od konce měsíce května do začátku měsíce srpna.
|
|
|
Vliv raného termínu odlistění zóny hroznů na kvalitu a zdravotní stav u bílých odrůd révy vinné
Pavlíková, Romana
This bachelor work focuses on timing, intensity and influence of defoliation on quality and physiology of grapevines. In the introduction, brief history of defoliation and mechanical devices used for defoliation are discussed. The main part describes an experiment testing different defoliation timing on Riesling grape quality. At the end of the main part, statistical analysis is presented. The experiment was done in the Mendel university vineyard, in Lednice, in the year 2015. In the end of the work, implications for planter praxis are discussed.
|
|
|
Construction and scientific implementation of mathematical models for tree compartments of broadleaved trees in growth stages of seedlings and young stand
Pajtík, Jozef ; Konopka, Bohdan (advisor) ; Monika, Monika (referee)
Importance of precise estimation for tree biomass in forests has been continuously increasing. Regarding to the climate change, scientists have started to quantify all tree components not only in terms of energetic utilization but also for carbon stock estimation. Increasing relevance of biomass models for young trees relates to expanding area of young forest stands during the last period due to decay of old forests often caused by disturbances (especially: windstorms, outbreaks of bark beetles, drought episodes, and forest fires). Models for biomass stock estimations constructed for stands with age to 10 years are rare and usually are focused on aboveground tree parts. Thus, this work aims at filling knowledge gaps in this field. Its main objectives are:
1) construction of regression models applicable for estimation of dry mass in the particular tree components (i.e. stem, branches, foliage, roots) for young stands of some broadleaved species,
2) implementation of regression models for calculation of biomass conversion and expansion factors (BCEF), allocation coefficient, growth efficiency and leaf area index (LAI) and their inter-specific comparison,
3) utilisation of allometric relations for estimation on forage potential for ruminating ungulate game (i.e. browsing and stripping).
To make up the models, destructive tree sampling will be implemented. The sample trees will be excavated, separated into tree components, dried for constant weight and weighed. Log-transformed relationships will be used for construction of regression models.
|
|
|
Vliv odlistění révových keřů bílých odrůd na regulaci cukernatosti a kyselin v hroznech
Holešinský, Radim
The main aim of this bachelor thesis was to determine the effect of the defoliation zones to regulate the sugar content of grapes and the content and composition of acids in the grapes. In the introduction describes the meaning and function of leaf area. The following is a description of the composition of the berries, basic sugars and acids, their development in the berries during the growing season and the impact of sugars and acids on wine quality. In the next chapter the importance of agro-technical action contributing to the formation of leaf area. In the end is described defoliation zones grapes. What does it mean defoliation, what are the most appropriate terms, the extent and intensity of defoliation and defoliation recommendations into practice.
|
|
|
Hodnocení defoliace vinic s ohledem na stanovení rozsahu redukce listové plochy
Tisarová, Mária
This thesis deals with the evaluation of defoliation of vineyards with respect to determination of extent of leaf area reduction in the varieties Hibernal, Zweigeltrebe and Cabernet Moravia. The experiment was conducted in 2013 at the experimental sites in the cadastral area of Lednice in Moravia and Rakvice. The development of leaf area was evaluated by ADC device BioScientific Ltd. during three periods (June, July, August) in the phenological stages of flowering phenological stages of fruit development and ripening of the fruit phenological stages. From the measured data was determined leaf area index (LAI) and the extent of defoliation. Using analytical methods parameters of quality grapes were evaluated - the sugar content, pH, acidity, assimilable nitrogen, and others in order to determine the optimal time of reduction in leaf area of a vine. Part of this work was also the evaluation of operating costs for Defoliator.
|
|
|
ECOLOGY APPLICATIONS IN THE GLASSHOUSE WITH THE SOLAR GRIDS
LESKOVCOVÁ, Martina
This Bachelor´s thesis is concerned with an observation of plants, especially generic beans (Phaseolus vulgaris L.), which were grown in front of varicoloured walls of greenhouse with solar rasters four years ago. It was supposed, according to a way of reflected solar radiation from the coloured walls, a different growth ability of plants in regard for leaf areas, a gross biomass, some of growth parameters of leaves and a photosyntetic rate as well. There was not discovered any possibility of influence of the walls relating to leaf areas, a weight of biomass and the photosyntetic rate. The influence was only set down in some of the parameters of leaves.
|
guest ::
