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Influence of understory light on diversity and composition of forest vegetation in the České Středohoří Mts.
Macek, Martin ; Kopecký, Martin (advisor) ; Černý, Tomáš (referee)
Light is essential component of forest ecosystem, as limited light availability in forest-floor restricts herb and tree seedlings growth. Importance of light availability for maintaining plant species diversity and community structure wasn't sufficiently evaluated in the Czech Republic. This study focus on the ecological relevance of light availability on both landscape and local scale. Relationship of light to cover, diversity and species composition was quantified in the thesis. Dominant tree species affected light availability and its spatial variability. Light availability was along the soil reaction and slope most influential factor for large-scale species diversity. Within-site light variability affected plant diversity more than soil reaction variability. Measuring light by means of hemispherical photography seems to be an appropriate for studies like this. Light availability influnence on community compostition is weak in comparison with other environmental gradients.
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The effects of forest clearings on bird populations
Eršil, Lukáš ; Policht, Richard (advisor) ; Ferenc, Michal (referee)
The most widespread way of extraction of forest is still clearlcuting. It is almost impossible to find commercial forest without forest clearings. Forest clearing can be perceived as a special element in a connected forest. I am trying to find out the influence of these forest distributions on the bird community. I was interested how important the forest clearings will be in the different type of forests. In seven localities were collected set of environmental variability's and bird data, which were counted by point count method. There were deciduous and mixed forests as well as the coniferous monocultures. The data collection was conducted in the breeding season 2011 and 2012. I expected, that the forest glades ensure the heterogeneity in forest space and will increase the number of bird's species. I expected this influence more important in the coniferous than in the deciduous and mixed forests. This assumption was partly confirmed. The glades in the coniferous forests have higher influence, but it depends on the forest area. In large coniferous monocultures is the importance of glades high. In the case of deciduous and mixed forests the size of forests did not have a value. The tree richness has the bigger importance. With this variable correlate Common Chiffchaff, Eurasian Wren, Yellowhammer,...
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Influence of understory light on diversity and composition of forest vegetation in the České Středohoří Mts.
Macek, Martin ; Kopecký, Martin (advisor) ; Černý, Tomáš (referee)
Light is essential component of forest ecosystem, as limited light availability in forest-floor restricts herb and tree seedlings growth. Importance of light availability for maintaining plant species diversity and community structure wasn't sufficiently evaluated in the Czech Republic. This study focus on the ecological relevance of light availability on both landscape and local scale. Relationship of light to cover, diversity and species composition was quantified in the thesis. Dominant tree species affected light availability and its spatial variability. Light availability was along the soil reaction and slope most influential factor for large-scale species diversity. Within-site light variability affected plant diversity more than soil reaction variability. Measuring light by means of hemispherical photography seems to be an appropriate for studies like this. Light availability influnence on community compostition is weak in comparison with other environmental gradients.
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Diversity of forest vegetation in the region of České středohoří
Tydlitátová, Klára ; Sklenář, Petr (advisor) ; Hédl, Radim (referee)
Abstract The topography of the Milešov part of the České středohoří Mts represents a suitable model for study of spatial distribution of diversity and the effects of ecological factors on species diversity and composition. Near-natural forest vegetation was sampled at eleven hills by stratified-randomly sited relevés. Soil samples were collected in relevés at nine hills also. The soil samples were used for maximal capillary capability, pH, carbon and nitrogen volume analyses. These ecological factors, as well as tree cover, altitude and heat load index, were used for examination of the correlation of ecological factors with diversity, species richness and species composition. Positive relationship between species richness and heat load index and soil reaction was identified. Species diversity (Shannon index) positively correlates with soil reaction also. After partialling out geographic components in the samples, a significant correlation between the heat load index, tree cover and altitude and species composition of the herb and shrub layer was found. Values of alpha and beta components were rated using partitioning of diversity to alpha and beta components at four levels (relevé - aspect - hill - landscape). The beta component at the aspect level and the beta component at the hill level were...
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Vliv hospodářských zásahů na změnu v biologické rozmanitosti ve zvláště chráněných územích: Vliv hospodářských zásahů a dynamiky prostoru na stav půd a přízemní vegetace lesních ekosystémů ve zvláště chráněných územích
Česká zemědělská univerzita v Praze, Fakulta lesnická a environmentální, Katedra pěstování lesů, Praha ; Viewegh, Jiří ; Podrázský, Vilém
Tato zpráva dokumentuje aktivity pracoviště, LF ČZU v Praze, jako spoluřešitele výzkumného projektu. Zahrnuje literární rešerši k degradaci stanoviště vlivem odstranění humusové vrstvy, dále k vlivu výchovných zásahů na dynamiku půdní organické hmoty, ke vlivu změny druhové skladby na stav humusových forem a v závěru uvádí půdní charakteristiky významné z hlediska ekologické stability a managementu lesních ekosystémů. Vlastní šetření se zaměřilo na popis přízemní vegetace a na odběr půdních vzorků v určených oblastech, daných zadavatelem. K nim byly přiřazeny lokality: Žákova hora v oblasti Žďárských vrchů na Českomoravské vrchovině, dále pak oblast Smrčiny a tzv. Trojmezenského pralesa na Šumavě. Na těchto lokalitách byly provedeny fytocenologické zápisy a odebrány vzorky humusových forem na stanovištích s různým stavem lesních porostů a s různými hospodářskými zásahy, resp. s těžbou stromů (Šumava).
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Impact of metabolites of the forest vegetation on the chemistry of throughfall
Skřivan, Petr ; Navrátil, Tomáš ; Vach, Marek ; Špičková, Jitka ; Fottová, D.
The chemistry of throughfall is a result of numerous processes that affect the concentrations of its individual components in the original wet precipitation above the tree crowns. The precipitation entering the tree crowns is generally enriched throughout its interactions with the above - ground part of the vegetation. The samples of open place precipitation and throughfall have been collected since 1989 in the region of Kostelec n. Č.lesy. The monitored area is situated predominantly in the Nature State Reserve Voděradské bučiny on the bedrock of the Říčany and Jevany granites. The exact evaluation of the impact of metabolites on the resultant concentration and fluxes of individual monitored elements in throughfall, based on mere comparison with the corresponding values in open place precipitation, is faced with several problems. First, the chemistry of throughfall reflects more the chemical composition of aerosol from lower parts of the atmosphere, as it is more or less effectively swept out by the above ground growth. The vegetation surface also entraps the reactive atmospheric gasses. Finally, the original precipitation solution is thickened through the evapotranspiration and it is enriched by the excluded and leached metabolites. The estimate of the extent of metabolic activity of the forest trees on the chemistry of throughfall was therefore limited on the comparison of a relative magnitude of normalised fluxes of individual elements in a given type of throughfall. The fluxes of individual elements in a beech- and spruce throughfall were normalised on the Na fluxes, with respect to the supposed zero metabolic share of Na in throughfall and to its predominantly natural sources in the atmospheric aerosol. The calculation of the enrichment factor Ef of the individual elements was then executed by means of the relation EfTFB,TFS (Me) = FBP Na / FTFB,TFS Na* FTFB,TFS Me / FBP Me, where EfTFB,TFS (Me) is the enrichment factor od the particular element in a given type of throughfall, FBP Na a FBP Me are the mean annual deposition fluxes of Na and the element Me on an open place, and FTFB,TFS Na a FTFB,TFS Me are the mean annual fluxes of Na and the element Me in throughfall. Values of the enrichment factor for the individual elements are presented in the article in the Tab. 1. Values higher than 1 should generally indicate the presence of metabolic products of the vegetation. The highest Ef values were found, after expectations, for the basic nutrients and significant essential elements, in a row of K > Mg > Mn > Ca. Together with these elements, significant impact of leached metabolites was also found for Rb, Sr and Ba. The enrichment of throughfall with rubidium is extraordinary high, probably even higher than that of its homologue potassium. Surprisngly high values of the Rb deposition fluxes in both tyes of throughfall certify the extensive input of this element through the root uptake of the forest vegetation, which is contingent on very close chemical characteristics of rubidium and potassium (ionic radii, electronegativity, ionic character of bonding of these alkaline metals in all their chemical compounds etc.). We have not found, however, similar pronounced paralell between Ca, Sr and especially Ba, which is even more abundant in the underlying rocks and soils than Sr.
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