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Turnover of aboveground biomass in a dominant species of a wet meadow
MEJDOVÁ, Markéta
This Bachelor{\crq}s Thesis is a part of the SP/2d1/93/07 (Czech Terra) project of the Department of Environment, which is focused on an assessment of carbon cycle and carbon balance in selected ecosystems of the Czech Republic. Within this project there is assessed production of aboveground biomass of wetland vegetation in the location of Mokrá luka (Wet Meadow) near Třeboň. In the presented Bachelor{\crq}s Thesis I focus on documentation of conversion of aboveground biomass of tulfted sedge (Carex acuta L.), which represents a dominant of the flooded part of Wet Meadows. My thesis consisted in non-destructive observation of aboveground biomass accumulation in selected humps, during which I assigned dry mass value to tillers growing in these humps on the basis of an analogy with parallel samples. At the selected tillers I observed dynamics of leaf growth during vegetative season, their drying up and falling. In this thesis I also deal with the differences in growth dynamics at generative and vegetative tillers. During their growth the generative tillers had on average only three leaves; in total they had on average seven leaves, which means that four leaves started to grow in previous autumn. Since seeding the leaves were dieing and the last live ones were observed on 13 August. During August and at the beginning of September the leaves started to fall more. At vegetative tillers the number of leaves during the growth period increased. At the beginning of measurement of these dynamics (4 June) the tillers had on average 10 leaves, from which three were from the previous autumn; by September their number increased to 14. During the growth period the tiller had 5-6 photosynthetic active leaves. The leaves fell more slowly than at generative tillers.
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Study of light microclimate in a chosen vegetation type during vegetation season
STOLIČKOVÁ, Martina
The aim of Bachelor thesis is the analysis of light microclimate depending on the production profile of sedge vegetation ( Carex acuta L. ) during the growing season. The light transmission of the growth of sedge and its changes during the growing season were examined. Then the seasonal cycle of the incoming and reflected solar radiation, including the albedo was evaluated.The seasonal changes in increase of aboveground live biomass, the amount of dry matter in the vertical vegetation profile, the distribution of leaf covering and the extinction coefficient changes during the growing season were assessed. The study of light microclimate and the biomass sampling was conducted in Mokré Louky near Třeboň close to pond Rožmberk. The largest representation of plant species has got Slender sedge ? Carex acuta L. there. The findings of relative insolation and light transmission was measured by pyranometer and the sampling of aboveground part was conducted by destructive method. These results show that the transmission is the highest at the vegetation surface and it decreases with the declining height. In August there was a radical decrease in the impact and the reflection of solar radiation due to the higher concentracion of water in the soil and air and this led to a reduction in albedo. Live biomass was measured: in July 1820g, in August 1670g and in September 1789g.The values of LAI and dry matter, recorded from July to September,were gradually decreasing and with the growing measured layer of growth there was a reduction in amount of dry matter and value of leaf area index.The extinction coefficient value varies depending on the age of stand. With the vegetation age the extintion coefficient increased up to 200,38. The Bachelor Thesis was developed within the research project of Faculty of Agriculture MSM 6007665806 ? The sustainable methods of farming in the foothills and mountainous areas,aiming to create harmony between their production and non-production application?.
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Factors determining soil respiration rate in herbaceous wetland ecosystem
STARÁ, Alžběta
Annotation: Soil respiration represents an important flow of CO2 between atmosphere and soil. Carbon bounded in the process of photosynthesis may be fixed in soil, but also may be released back to atmosphere in the form of CO2. An accurate evaluation of global carbon balance is a key for the estimation of future development of atmospheric concentration of CO2 and prediction of climate changes. The soil respiration of selected wetland biotopes with graminoid vegetation was studied in relation to concentration of soil carbon, nutrient availability, soil moisture and soil temperature during the vegetation season 2008. The observed wetlands included a locality located near the village of Hamr with mineral soil and the nature reserve Záblatské meadows with organic soil. Soil respiration was measured as CO2 release from soil with the use of the equipment LiCor 6400 with soil chamber. The influence of fertilizer application on CO2 release was not proved for either locality. A relationship between soil respiration and soil moisture was found on Záblatské meadows, where the CO2 release declined with increasing soil moisture.
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Decomposition of aboveground biomass of a herbaceous wetland stand
KLIMOVIČOVÁ, Lucie
This work deals with the decomposition of aboveground vegetation in wetlands. The decomposition process leads to the release of greenhouse gases, which are currently being studied primarily in relation to current climate change. The decomposition rate was established on the flooded part of the Wet Meadows near Třeboň. The intensity of degradation processes was evaluated using the litter-bag method. Bags of dry matter were located in the vicinity of the automatic meteorological station at four randomly selected sites in April 2009. The litter bags were fixed so that their positio followed the natural positionof the standing dead matter. Values of the decomposition rate were assessed for two sampling, summer and autumn 2009. The obtained values of decomposition rates are discussed with the results of Kovářová who used the litter-bags method on Wet Meadows near Třeboň in the past.
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Effect of inter-annual differences of selected meteorological parameters on species composition of the Wet meadows near Třeboň
FRANCOVÁ, Kateřina
The aim of this thesis is to evaluate the inter-annual differences in species composition of selected stands of a wet meadow ecosystem in relation to determining meteorological parameters. Changes in plant communities were studied in selected parts of the Wet meadows near Třeboň. Inter-annual differences were found only in the cover of dominant species, but not in the constancy of species.The average cover of Phalaris arundinacea was greater in 2007 than in 2006. A further increase was observed in 2007 in the cover of Calamagrostis canescens, whose presence on the wet meadows was previously limited by the floods in 2002. Calamagrostis canescens again appeared on the Wet meadows in 2006, but its growth was promoted only in the drier year 2007. The results show that the community is relatively stable in relation to short-term fluctuations of the weather.
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Effect of fertilization on primary production of a herbaceous wetland stand
LAZÁRKOVÁ, Kateřina
This thesis is part of the project GA CR No 526/09/1546 (``Importace of newly assimilated carbon to the interaction of plants with soil in grassland and wetland ecosystems in varying environmental conditions``). The goal is to establish aboveground crop production of the Wetland Nature Reserve Záblatské meadows near Třeboň and determine whether fertilization in previous years has an influence on species composition and production. Aboveground biomass was established in June 2009 by the destructive method. Overall, 24 samples (yield + stubble) were collected from 12 sites. The samples were taken from plots of 0.5 x 0.5 m. The biomass values were expressed per an area of 1 m-2. Effect of fertilization was studied in areas subjected to different doses of fertilizer from 2006-2008: 300 kg NPK. ha-2 (HI treatment), 65 kg NPK. ha-2 (LOW treatment) and unfertilized (NO treatment). Total aboveground biomass was 723,05 g.m-2 in the HI treatment, 711,12 g.m-2 variants in the LOW treatment and 712,72 g.m-2 in the NO treatment. Long-term fertilization suppressed the production of mosses.
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Effect of N eutrofication of wetland soils on organic N content and quality
ŠEDA, Martin
This study deals with an effect of fertilization on amount and quality of free amino acids in soil from wet meadows affected by nutrient loading. Free amino acids were analysed in the soil from the field experiment situated at wet meadows, where an increased nutrient input is simulated (fertilizer NPK). The experiment was established on two sites with different types of soil {--} Záblatí with organic soil and Hamr with mineral soil, both areas in the South Bohemia region. The soil was repeatedly sampled for more than two years and year. One part of this study is focused on testing of ninhydrine-method and HPLC-method for measuring free amino acids and efficiency of different extractants.
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Role of wetlands in water budget of landscape
Pokorný, J. ; Lhotský, R.
Wetlands are unterstood as shallow, seasonally or permanently waterlogger or flooded areas which normaly suppostr hydrophytic vegetation. Various definitions of wetlands are given. Water retention above soil surface, in wetland soil and role of wetland plants in water cycle and solar energy dissipation are briefly explained. Examples of long term monitoring water retention in a peat bog and functioning of a wetland landscape during flood are given. Role of watelands in landscape restoration is mentioned.
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