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Regulace fotosyntézy a primární produkce fytoplanktonu za podmínek nutričního a světelného stresu.
FELCMANOVÁ, Kristina
Regulation of photosynthesis and primary production in globally important cyanobacterium Prochlorococcus marinus under nitrogen and light stress were examined. The study investigated the model describing relationship between photosynthetic activity and primary production. The photosynthetic energy budget and the efficiency of converting the photosynthetic energy into biomass were described. Molecular and physiological approaches were applied to analyse the utilization of photosynthetic energy and regulation of metabolism to investigate the influence of streamlined oxygen-evolving cluster on the photosynthetic activities.
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Microorganisms as the primary producers in photosynthesis-independent ecosystems
Burkartová, Kateřina ; Falteisek, Lukáš (advisor) ; Lhotský, Josef (referee)
Chemolithotrophy and photoautotrophy are the two basic principles of primary production on Earth. This thesis focuses on the relation between chemolithotrophic and oxygen-productive photosynthetic microorganisms in a global dimension. There are high atmospheric oxygen concentration, high sulfate in seawater and other oxidants because of oxygen-productive photosynthesis. These compounds are commonly consumed by chemolithotrophs to oxidize reduced inorganic compounds. It is a question, if there are chemoautotrophic ecosystems profiting only from abiotically derived substrates. It is essential to combine geochemical and metagenomic approaches in order to enhance both establishing of the origin of substrates and assessing the metabolism which utilizes them in the tested ecosystem respectively. Two well established types of photosynthetic independent ecosystems that use serpentinization hydrothermal venting and radiolysis of water as a source of energy are known at present time. The absence of photosynthesis-derived final electron acceptors for chemolithotrophy and the proper spatial separation from areas where photosynthetically derived organic matter and oxidants are present can be a useful clue for this investigation. The goal of this thesis is to describe geological processes which provide not only...
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Photosynthetic characteristics of phytoplankton in eutrophic waters
Tesařová, Blanka ; Pechar, Libor (advisor) ; Fott, Jan (referee)
Photosynthesis and primary production were estimated in fishpond phytoplankton during period 2008-2010 in Třeboň fishpond region, Czech Republic. Photosynthesis was measured by the oxygen method in computer-assisted light pipetting system Illuminova. Altogether 64 samples of fishpond phytoplankton and 11 cyanobacterial cultures were analysed. Cyanobacteria and chlorococcal algae formed the most important part of phytoplankton biomass and their photosynthesis-irradiance (P-I) curves showed shade-adapted type of P-I curves with the high photosynthetic efficiency. No significant differences in the main parameters of P-I curves were obtained between different types of phytoplankton (chlorococcal-dominated, cyanobacteria- dominated). The results are consistent with the high turbid conditions in eutrophic or hypetrophic fishponds. On the contrary photosynthesis in cyanobacterial cultures differs from "wild" phytoplankton and therefore they can not be taken in primary production models. Primary production was estimated according Talling's model (1957), based on daily measurement of radiation, extinction coefficient of water and seasonal courses of chlorophyll concentration. Photosynthetic capacity and onset of light saturation determined in P-I curves were used as physiological parameters of Talling's model. The...
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Development of concept of ecological footprint
Vrbová, Anna ; Albrechtová, Jana (advisor) ; Lhotáková, Zuzana (referee)
The ecological footprint is an indicator that measures the size of the bioproductive land needed to provide resources and disposal of waste from existing technologies.It's an important sign of the sustainability of the population on Earth.As we are currently facing an impending lack of many natural resources,this is an important issue.The biomass we use is created by plants,which play a critical role not only in functioning of the ecosystems,but in the concept of the ecological footprint.Individual types of vegetation differ in their relative contribution the overall ecosystems production and consequently to the calculation of the ecological footprint of various lands.For this reason this work is concerned not only with the concept of the ecological footprint, but also with the services that plants provide.The objective of this work is to compile the current information on the evolution of the concept of the ecological footprint,what preceded its creation,and to focus on the important role of plants in the functioning of ecosystems,allowing for the calculation of the ecological footprint.The evolution of the concept of the ecological footprint is covered in Chapter 1.Chapter 2 deals with ecosystem services,their rating,and the critical role that plants play in them.The calculation of the ecological...
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Respiration of zooplankton in eutrophic ponds
LENDLEROVÁ, Lucie
Respiration in ponds recycles organic carbon arising from photosynthesis back to inorganic carbon. Zooplankton is most important in the process of respiration in the pond. Prior to this transformation, the organic carbon is potentially available to support secondary production. The efficiency of primary and secondary production relative to respiration is an important feature of ponds and other aquatic ecosystems. Intensive respiration in sediments often leads to oxygen depletion and even anoxia. Thus, the rates and controls of respiration are of central importance in pond ecosys-tems. The results show that zooplankton respiration make 60% or more of system respiration in the spring stage of clean water. There may be situations when it is pos-sible increase of benthic filamentous algae thanks to high transparency. Their photo-synthetic assimilation effectively balances oxygen deficit caused by zooplankton respiration and not occur dangerous deficit situations for fish which are usual in this period.
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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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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.
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