National Repository of Grey Literature 27 records found  previous11 - 20next  jump to record: Search took 0.00 seconds. 
Bryophytes distribution modelling
Procházková, Martina ; Man, Matěj (advisor) ; Fialová, Lucie (referee)
The aim of this bachelor thesis is to summarize recent knowledge about Species Distribution Modelling in botany, focusing on bryophytes. Species Distribution Modelling is used to explain the relationship between species occurrences and environmental conditions of their habitats. This method has unused potential in bryophytes compared to vascular plants. The distribution of bryophytes is influenced by their dispersal and ecological characteristics. The most important factor is a close association between bryophytes and microclimatic conditions of their habitats. This association is studied, but is not yet incorporated in the modelling process along with using data in an appropriate scale. Currently there is an increased interest in bryophytes distribution modelling. In Europe, there are some studies using this method for bryophytes mainly in Iberian Peninsula, Italy and northern Europe. There are approximately 25 articles focused on bryophytes distribution modelling worldwide. This method can be used for ecological niche modelling, in biogeography and for prediction of distribution in future climate. The use of bryophytes distribution modelling for their conservation is also significant. Bryophytes distribution models can successfully predict potential distribution of rare or endangered species and...
Natural sources and sinks of volatile chlorinated hydrocarbons in the spruce forest ecosystem
Štangelová, Pavla ; Tesařová, Eva (advisor) ; Pavlík, Milan (referee)
Biogeochemical cycle of chlorine, particularly the formation of organically bound chlorine is still not well understood. In continental ecosystems chlorides act as source of chlorine, and also as a stress factor. Chlorides originate from precipitation of marine cloud masses. Organically bound chlorine in the environment is formed naturally by biotical and abiotical way. The biotical factors are microorganisms, plants, soil enzymes and animals. Volatile chlorinated hydrocarbons (VOCl) represent one group of organically bound chlorines. Several volatile chlorinated hydrocarbons reacts with atmospheric ozone, consequently causing depletion of the ozone layer. The most important known terrestrial source of volatile chlorinated hydrocarbons is the spruce forest ecosystem. Chlorine in the soil can be transformed by microorganisms into organically bound chlorine or translocated by transpiration stream in plants, where they are also transformed enzymatically into organically bound chlorine, and both of them can be emitted into the atmosphere. Too large amounts of chloride can affect the physiological functions of plants. In this thesis experiments were designed for measuring the natural emissions of volatile halogenated hydrocarbons from plants and fungi, with various periods of incubation, and also to...
Bryological Oriented Excursion in the Dolský mlýn Area
Davídková, Markéta ; Novotný, Petr (advisor) ; Skýbová, Jana (referee)
The aim of this thesis was to carry out an analysis of primary school textbooks considering bryophytes and bracken, as well as to plan a biological excursion in the area of Dolský Mlýn which would include mapping the terrain. The sixth chapter contains the analysis of nine textbooks from different publishing houses. I have compared them in terms of the number of pages dedicated to bryophytes and bracken and in terms of the number of stated bryophytes and bracken representatives. I have also compared whether the textbooks are provided by workbooks, methodological guides and other material, which could variegate biology and natural history teaching. The seventh chapter characterises the location. Mapping of the terrain for the planned excursion took place in September 2012. I chose fourteen suitable sites which are were easily accessible. The eight chapter includes methodical instructions of the excursion for teachers, worklists and the key to determining types of bryophytes. The practical verification of my thesis took place in April 2013 during an excursion of seventh grade pupils from the school ZŠ a MŠ Děčín IV. Laboratory training, which represents an integral part of the excursion took place in March due to unfavorable chmate conditions. Pupils determined mosses of genus Merike according to their...
Biology of epiphytic bryophytes: methods of study
Reitschmiedová, Erika ; Soldán, Zdeněk (advisor) ; Novozámská, Eva (referee)
This thesis is aimed to provide basic description and summary of methods used to study biology/ecology of bryophytes, especially epiphytes. Described methods include study of mosses and liverworts; hornworts are not included due to the fact that their epiphytic form is not known. There are five chapters in this thesis, all of them are primarily focused on description of basic or most useful methods for studying phenology, growth, bioindication and environmental conditions, e.g. light and water relationship measurement as well as bark pH measurement. The last one, "Forms and Strategies", is only terminological and it includes terms of life and growth forms and life strategy which are used in studying colonies of bryophytes.
Natural Sources of Chlorinated Volatile Hydrocarbons in Spruce Forest Undergrowth
Štangelová, Pavla ; Wimmer, Zdeněk ; Tesařová, E. ; Forczek, Sándor
Chlorine as one of the most frequently occurring elements in nature, is involved in biogeochemical\ncycles. Several anthropogenic and even natural sources of volatile chlorinated hydrocarbons of\nemission is known, yet natural sources have not been explored enough. The aim of this study is to\ngather information of potential sources of chlorinated organic hydrocarbons in spruce forest\nundergrowth. Emissions of chlorinated volatile hydrocarbons of selected species of bryophytes,\nferns and fungi were measured by SMPE sampling technique and analyzed with GC-MS analysis.\nSodium chloride solution was used as a stressor to simulate increased environmental chloride load.\nTrichloromethane (chloroform) was found in most natural samples, dichloromethane,\ntetrachloroethene and tetrachloromethane were found occasionally. Increased chloride\nconcentration caused elevated emissions of trichloromethane and tetrachloromethane in some plant\nspecies.
Aspects of reproduction biology of the moss \kur{Helodium blandowii}
BRADÁČOVÁ, Jitka
Regeneration from stem and branch fragments of the moss Helodium blandowii was examined in common garden and field experiments. The treatments included one cm long terminal stem fragments and branches of one cm and half cm length with and without the terminal and their regeneration was observed in course of 3 months in the common garden experiment and 15 months in the field. Dynamics of Helodium patches was observed in course of 2 years in permanent plots of the nature reserve Ruda. Genetic stucture of all recent Czech populations of Helodium blandowii was investigated and compared with a pilot survey of populations from Scandinavia and Lithuania using the microsatellite markes developed for this study.
Bryophytes of dry grasslands in southern part of PLA Český kras
TENČÍK, Aleš
The aim of the thesis was to survey the occurrence of mosses in the different types of calcareous dry grasslands in the southwestern part of the Bohemian Karst and assess the impact of major abiotic and biotic factors to their diversity.At seven habitat types was acquired a total of 35 plots of 1x1 m. The most important factor influencing the diversity of mosses turned out to be the degree of coverage of herb layer markedly influenced by used type of management.Dry grasslands with Festuca pallens (T3.1) and Sesleria grasslands (T3.2) appeared to be rich in moss species. Conversely mossy low diversity here is presented by broad-leaved dry grasslands (T3.4).
Aspects of reproduction biology of the moss \kur{Helodium blandowii}
BRADÁČOVÁ, Jitka
Regeneration from stem and branch fragments of the moss Helodium blandowii was examined in common garden and field experiments. The treatments included one cm long terminal stem fragments and branches of one cm and half cm length with and without the terminal and their regeneration was observed in course of 3 months in the common garden experiment and 15 months in the field. Dynamics of Helodium patches was observed in course of 2 years in permanent plots of the nature reserve Ruda. Genetic stucture of all recent Czech populations of Helodium blandowii was investigated and compared with a pilot survey of populations from Scandinavia and Lithuania using the microsatellite markes developed for this study.
Photosynthesis, production and growth of plants under temporal light hererogeneity
KUBÁSEK, Jiří
In this Ph.D. thesis I am dealing with the effect of dynamic irradiance on (i) photosynthesis, growth and bundle sheath leakiness (for CO2) of C4 plants and (ii) bryophyte photosynthesis. Part of this thesis is literature review on broader aspects of the dynamic light effects on photosynthetic and growth processes in plants.
Effect of management on three moss species of fen meadows (Breidleria pratensis, Sphagnum warnstorfii, Tomentypnum nitens)
VELEHRADSKÁ, Tereza
Effects of different types of management (control, mown, mown + disturbed (gaps) + litter removed) on three moss species of fen meadows were studied. Experimental plots were established at sixteen sites in the Bohemian Forest, in the foothills of the Bohemian Forest and in Českomoravská vrchovina. Relevés and micromaps of bryophytes in the plots 0.5 × 0.5m were sampled at the beginning of the experiment during the summer season of 2010 and then after 3 seasons (during the summer season of 2012) of performing management. The age of the abandoned meadows was also determined and values of pH, conductivity and height of water level of each plot were measured. Positive influences of both types of management on the cover of Tomentypnum nitens and of management with creating gaps and remowing of litter on the cover of Breidleria pratensis were significant. Effect of management on the Sphagnum warnstorfii was significant only when processes of remaining on already occupied places and the expansion to new places were tested separately. Enviromental values did not significantly influence the change of cover of any species between 2010 and 2012. In conclusion, it is clear that diverse management with reasonable use of these practices (mowing, creation of gaps, litter removal) is desirable for maintaining of vital and diverse bryophyte layer.

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