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Changes in timing of germination caused by neighbouring seeds and how it is connected with species traits.
Kos, Pavel ; Weiser, Martin (advisor) ; Hadincová, Věroslava (referee)
The time when the seed germinates is very important. Ability to change the time of germination may be very advantageous. It allows the emerging seed to choose the best time according to abiotic conditions, and also to avoid of competition with neighbouring individuals. The seed reacts not only on adult plants and seedlings, but also on other seeds, with which is able to communicate. For a better understanding to this mechanism I conducted an experimental study with twenty-six species. The species were selected according to their position in long succession seres of mesic/xeric abandoned fields in Český kras. The seeds were left to germinate in pairs in all combinations among them. Here I present the results where I show how the time of emergence changes, depending on presence of neighbouring seed. Also, I show how these changes in germination are related to species specific traits. Out of this, I tried to influence communication between seeds by adding activated carbon. Activated carbon should stop the communication by highly absorbing surface. The time of germination of seeds which germinated alone was not proportional to the time of germination of seeds which germinated with neighbours. This correlation showed up like nonlinear, late-emerging seeds emerging unproportionally later when emerging...
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Wildfire as an ecological factor in the forests of Central Europe
Adámek, Martin ; Hadincová, Věroslava (advisor) ; Svoboda, Miroslav (referee) ; Nagel, Thomas A (referee)
Within the Northern Hemisphere, wildfires are considered to be an integral part of natural dynamics mainly in boreal forests and Mediterranean ecosystems, and most recently also in temperate forests of Northern America. By contrast, in temperate forests of Central Europe, the importance of wildfire for forest ecosystems has been traditionally marginalised despite documented frequent wildfire occurrence and existence of fire-prone forests. Apparently, the reason of this rooted attitude does not lie in the specific environmental conditions of Central Europe, but more likely in the traditional forest ecology approach, which generally does not consider the effect of disturbances on the shape of vegetation communities and strictly excludes human activity from natural processes since its beginnings. This attitude resulted in the lack of knowledge about local vegetation-wildfire relationship and patterns of wildfire occurrence in the landscape. The general aim of this thesis was to clarify the ecological role of wildfires for Central European forest ecosystems with a focus on Pinus sylvestris forests and using the Czech Republic as a model area for a broader region. Chapter 1 deals with the spatial analysis of the occurrence of forest fires in the Czech Republic. We found that the presence of wildfire in...
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Vegetation succession at the clearings at the pine forest areas
Šmidrkalová, Monika ; Hadincová, Věroslava (advisor) ; Prach, Karel (referee)
Vegetation succession at the clearings at the pine forests areas was studied in the sandstone landscapes of the Czech Republic (Bohemian Paradise, Doksy region, Bohemian Switzerland). The aim of the study was to reveal the course of succession, the rate of changes, the factors influencing succession and the differences between the vegetation succession trajectory at the clearings and the burnt places. Space-for- time substitution method was used to record overall 249 phytocenological relevés (100 m2 ) at the clearings from 1 to 170 years, divided into 7 successional stages. The results showed the total number of species did not change significantly during the succession. There were differences in the species composition between successsional stages. The youngest successional stages (to 5 years) differed the most from the older stages by the occurence of shade-intolerant ruderal species. The eldest stages (over 40 years) were similar in the species composition. The type of planted tree and locality influenced the species composition the most within 10 years. The comparative study between the succession at the clearings and the burnt places showed significantly lower total number of species at the clearings. The development of the...
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Early vegetation succession at conifer forests in CR
Šmidrkalová, Monika ; Hadincová, Věroslava (advisor) ; Macek, Martin (referee)
In coniferous forests take place natural or human-made disturbance processes (wind, fire, pests, logging,…), which disrupt forest landscape. These processes are the main force driving the forest dynamics around the world. Damaged or destroyed sites in forest after disturbances immediately starts regeneration. Forest development on disturbed sites depends on various abiotic and biotic factors, which are: seed availability (seed sources, distance from clearing, disturbed site size, dispersal ability, surrounding vegetation effect), suitable stand (open site, climatic conditions of site, soil properties, site topography, presence of animals) and site history before disturbance. Idealized course of succession, take place in forests after disturbances, starts with ruderal annual species entrance and it is continued with herb perennials and shrubs followed by early-successional trees and late-successional trees. The most common method in research of succession is phytosociological sampling of different aged successional stages. Vegetation succession on disturbed sites in coniferous forests of the Czech Republic has not been described a lot so far and we also particularly miss studies researching a succession in the areas of pine forests with dominating Scots pine (Pinus sylvestris). Key words: forest,...
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Habitat requirements of two species Huperzia selago and Lycopodium annotinum in sandstone area of NP Bohemian Switzerland
Trachtová, Pavla ; Hadincová, Věroslava (advisor) ; Adámek, Martin (referee)
Species Huperzia selago and Lycopodium annotinum occur in cold and humid habitats with acid substrate. These are mainly mountain areas in the Czech Republic, but also sand gorges, where the temperature inversion is common. The temperature inversion causes the fact, that temperature conditions in ravines are different from the climatic conditions of surroundings, which causes high rate of species variety among the habitats. In these places, Montane and Boreal species grow in low altitudes and in the proximity of thermophile species. The presence of montane and boreal species in sand ravines is largely influenced by inherence of temperature inversion, which is determined by features of ravine (depth, breadth, orientation) and by weather conditions. Other important agents (excepting microclimatic conditions), which influence the prevalence of these kinds, are microelement availability and the rate of competition. In Czech Republic, both species Huperzia selago and Lycopodium annotinum fall into C3 category, which means that they indicate permanent regression in our nature. In the case of my field survey in the area of the Bohemian Switzerland National Park I confirmed this tendency for species Huperzia selago.
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Long distance dispersal of Rumex alpinus
Řičařová, Veronika ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Long-distance dispersal of Rumex alpinus was studied in the Giant Mountain in the National Park. The invasion of R. alpinus is there kind of problem. The work builds on a thesis from year 2007 (20007 Červenková), in which was made the model of the invasion of R. alpinus in the area of the Giant Mountain. The measurements of the seeds spread take place at four localities, three of them were for measuring of water dispersal and one was for measuring of winter dispersal. Anemochory was measured using traps in the meadow up to a distance of 50 m. The seeds were dispersed by wind to a distance of 20 meters. Hydrochory was measured using a network's traps in the streams up to 100 m. The largest measured water dispersal was 100 m. Hydrochory therefore proved to be an important factor, which influenced the invasion of R. alpinus. The storms and flood had the great influence on the hydrochory and anemochory. The prediction exponential curves were compiled from the data about the wind dispersal. The curves express the spread to more than a measured distance. The field dispersion curves were compared with theoretical curves, which were used in the model of the invasion from 2007. It turned out that the theoretical curves overestimate the spread of R. alpinus by wind. The dispersion of seeds was underestimated in the...
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Study of ecosystem impact of giant hogweed (Heracleum mantegazzianum) invasion
Hladík, Marek ; Pergl, Jan (advisor) ; Hadincová, Věroslava (referee)
The present study deals with ecological impact of giant hogweed (Heracleum mantegazzianum) invasion in Slavkovský les area. Being one of the prominent invasive species with significant impact on human health it has been subjected to a wide research. In spite of that little is known about its impact on the invaded ecosystem. My research was therefore focused on analysis of the ecosystem impact, particulary 1) microclimatic measurements of temperature and soil moisture and their comparisons between invaded and noninvaded vegetation, 2) comparison of germination and survival of model plant species sowed into invaded and noninvaded plots and 3) study of the effect of H. mantegazzianum presence on model species seed production. Results have shown significant alteration of microclimate due to H. mantegazzianum invasion. Further research is needed to resolve what impact it may pose to species in invaded communities. The effect of Heracleum mantegazzianum presence on germination and survival of model species was not significant. Similarly, seed production of model plants was not significantly affected.
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Factors determining distribution of species in dry grasslands
Průchová, Dana ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Factors determining distribution of species in semi-natural grasslands Survival and colonization of plant species in fragmented landscapes are topic of many recent studies. Most of them deal with one or just a few species or with overall species diversity. There are also a lot of studies devoted to the effect of abiotic characteristics and other parameters of fragmented habitat patches. Studies that would enable to evaluate behaviour of a large number of individual species are still relatively rare, especially in case of grassland species. Comparison of species traits in conjunction with the knowledge of type of historical land use and abiotic requirements of species can be a key to understanding of current species dispersal and their regional dynamic in fragmented landscape. This method of prediction of species dispersal can be a good implement for landscape planning and conservation of species and also their habitats. Goal of my thesis was to determine which traits of species influence response of species on land-use history in fragmented habitat of dry grasslands. I tried to use effect of land-use history without effect of environmental factors on species composition in phytosociological relevés. Then I tried to explain the reaction of species through their traits. I focused partially on traits...
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Succession after reintroduction of grazing in dry grasslands
Fulínová, Martina ; Hadincová, Věroslava (referee) ; Münzbergová, Zuzana (advisor)
Grazing management is very popular nowadays and number of sites with grazing animals with the aim of restoring the sites is steadily growing. All the effects of grazing on grazed grasslands are not elucidated yet. This thesis focused mainly on the contribution of zoochory to restoration of species rich grasslands on stands cleared from Robinia pseudoacacia and stands cleared from Prunus spinosa brushwood. For the purpose of monitoring changes in vegetation, permanent plots have been established. In order to identify sources of new species occurring in permanent plots, inventory of species growing in neighbourhood of the permanent plots has been done, samples of soil seed bank, sheep buttons and seeds from sheep wool have been germinated in a greenhouse. Monitoring of permanent plots showed reduced regrowth of R. pseudoacacia and P. spinosa. We have also found that greater changes in species composition occurred in more degraded stands than in stands better-preserved. Germinating experiments proved soil seed bank being mainly the image of aboveground vegetation with minor importance to restoration of species rich grasslands. On the other hand sheep seem to be of great use for dispersal of seeds both by epizoochory and endozoochory when walking between different stands. This finding is of great importance for...
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