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Holocene fire history of forest vegetation in central Europe based on soil and sedimentary charcoal
Bobek, Přemysl ; Kuneš, Petr (advisor) ; Feurdean, Angelica (referee) ; Chytrý, Milan (referee)
Fire is a fundamental environmental factor that directly shapes many terrestrial ecosystems on Earth. The present thesis attempts to provide a comprehensive overview of the fire dynamics in Central Europe over the course of the last 12,000 years. Based on extensive analyses of charcoal particles deposited in terrestrial and lacustrine sedimentary sequences and carbonized plant tissues deposited in soils, I was able to track past fire dynamics across a range of spatial scales - from the forest stand scale to the landscape scale. First, we described relationships between drivers of recent fire occurrence and proposed linkages to the spatial pattern of Late-Holocene biomass burning. We found factors related to relief characteristics, such as increased thermal flux or terrain roughness, to be important determinants of fire occurrence within the present-day landscape. Contrary to all expectations, anthropogenic drivers seem to have a weak influence at present. Because relief-based factors have been stable throughout the Holocene, it seems probable that habitats of certain types are more predisposed to increased burning. We hypothesized that recurrent fire disturbances may contribute to the long-term maintenance of Pinus sylvestris-dominated forests, which withstood the competitive pressure of broadleaf...
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Vegetation changes in Czech lowland forests over the past decades
Kopecký, Martin ; Hédl, Radim (advisor) ; Chytrý, Milan (referee) ; Diekmann, Martin (referee)
Vegetation changes in Czech lowland forests over the past decades Martin Kopecký ABSTRACT To explore decadal changes in plant species diversity and composition of typical lowland forests in the Czech Republic, I compared vegetation on plots sampled decades ago with vegetation on the same plots sampled recently. First I evaluated the robustness of the approach used in my thesis. In Chapter 1, we provided the first direct test of the effect of uncertainty in original plot location on results from vegetation resurvey. We found that temporal trends in vegetation diversity and composition were comparable between exactly relocated permanent and only approximately relocated semi-permanent plots. Therefore, we conclude that the resurvey of semi-permanent plots is robust to the uncertainty in original plot location. Then, we showed that vegetation in lowland oak forest shifted from species-rich communities of thermophilous forest toward species poorer communities of mesic forest (Chapter 2). The species typical for thermophilous oak forests and nationally endangered species suffered the most significant decline. We identified as the main driver behind these changes shift from traditional coppicing toward high forest management after WWII. Further, we explored the processes behind temporal shifts in species diversity...
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Palynological synthesis for the Czech Republic
Abraham, Vojtěch ; Pokorný, Petr (advisor) ; Chytrý, Milan (referee) ; Sugita, Shinya (referee)
The aim is to gather pollen sequences and derive from them synthetic information on past species distribution and Holocene vegetation history. Lonicera nigra was selected as a model taxa. The phylogeographic hypothesis that its Alpine and Carpathian populations survived the LGM in separate refugia is supported only by the Late-Glacial record. This shrub migrated rapidly from southern to central Europe during the warm oscilations of the Late Glacial. The synthesis of vegetation history was produced by applying the REVEALS model, which can filter out following factors influencing the relationship between pollen and vegetation: pollen taphonomy, pollen productivity and pollen dispersal. It was necessary to calculate and test those parameters, so the goals were partly methodical. Pollen productivity estimates are calculated within the Relevant Source Area of Pollen, which is influenced by vegetation structure. Subsequent validation of those values in the area of the REVEALS model 10000 km2 and selection of additional values for lacking taxa created the best set of parameters for the study area. The source fossil dataset for purposes of this synthesis is the newly developed Czech Quaternary Pollen database (PALYCZ). Non-direct multivariate analysis of pollen percentages including all taxa revealed a similarity...
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Age and growth of the European grayling Thymallus thymallus (L.) originally from different localities - assessment based on the scale analysis
CHYTRÝ, Martin
The main aim of this thesis is to evaluate and to compare the age and length growth of European grayling in selected watercourse in the South Bohemia (Blanice vodňanská, Volyňka, Teplá Vltava a Otava) and in Austria (the Traun River and the Salzach River), focusing on the watersources of the Teplá Vltava River and the Traun River. Possible rules adjustment of sport fishing can give reasons eventually to be done on the basis of results in order to protect and to strenghten natural populatin of grayling. 53 individuals (fish) were studied in total which were in observed localities fished from 2011 to 2015 using power generator or fishing rods. The determination of age and growth were based on analysis of scales of the biggest individuals. The method of Rosa Lee (1920) was used for back-calculation of length growth. The oldest fish, 8 years old, was found among graylings in the Teplá Vltava River. The oldest fish from studied group of fish in Austrian Traun River where graylings trophy are occured belonged to the age group 5+. Graylings from the Traun River came up to faster growth distinctly which is related to more optimal living conditions (water temperature, the amount of food) in the pariticular watersource. Furthermore graylings from observed watersources in the South Bohemian region already grow up to minimum fishing length (30 cm) at the age of 3 4 years old. They can participate in natural reproduction only once or twice a life. Increase of miminal fishing length is absolutely eligible and it is the reason for increasing number of natural spawning and strenghtening of indigenous population of grayling.
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Ichthyofauna of selected sections of the Jizera basin
CHYTRÝ, Martin
Rivers fragmentation by migration barriers has a significant negative effect on native fish communities and other river organisms. That is the reason why there has been put a lot of emphasis on creating fish pass in rivers in recent years. Between the years 2012 and 2013 there were carried out investigations on the new slit fish pass on the Jizera River in Turnov. The aim was to assess the technical realization of the construction of fish pass and functionality for local ichthyofauna. Primarily we have focused on hydraulic conditions in the fish pass (water flow, velocity, level differences in all chambers). During the fish pass technical inspection the fish was being caught by electric aggregate. The species composition of fish was also measured in the weir. Catching weir was used to catch the counter-migrating fish through the fish pass. The caught fish was taken its body length in mm and weight in grams and subsequently was calculated numerical dominance, diversity and evenness. There were 519 pieces of fish caught weighing 6.395 kg in total. There was confirmed presence of 10 species of fish in the fish pass, while in the weir were found 3 more species of fish and 1 species of lamprey. Reproductive migration was confirmed for brown trout and minnow. Roach, dace, perch and chub have settled down in the resting chambers permanently. There have been found several defects in the fish pass. There have been found large differences between the levels of chambers, high flow rates, reduced light penetration of the water in the fish pass, lack of entry attractiveness of the fish pass and non-minimum residual flows. Fish passage is considerably clogged by suspended dirt and the cleaning possibility is limited. Functionality and selectivity of the fish passage has not been demonstrated. There will be further investigations carried out in 2013.
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Vliv hospodářských zásahů na změnu v biologické rozmanitosti ve zvláště chráněných územích: Vliv různých managementových zásahů na vegetaci vřesovišť v Národním parku Podyjí II.
Mendelova zemědělská a lesnická univerzita v Brně, Ústav půdoznalství a mikrobiologie, Brno ; Masarykova univerzita v Brně, Přírodovědecká fakulta, katedra botaniky, Brno ; Botanický ústav AV ČR, Průhonice, pracoviště Brno ; Záhora, Jaroslav ; Chytrý, Milan ; Tůma, Ivan ; Holub, Petr ; Sedláková, Iva
V roce 1992 byly založeny pokusy, které měly ověřit, zda vypalování, kosení a odstraňování drnů jako tradiční typy managementu západoevropských vřesovišť povedou k obnově a zmlazení vřesovišť v NPR Podyjí. Dále bylo v roce 2000 založeno 30 nových ploch na studium vlivu pastvy a kosení. Od roku 2000 je také sledována dynamika mikrobiálních transformací dusíků v půdě, rychlost rozkladu opadu a efektivita využití N a P rostlinami. V roce 2001 byly na vřesoviště naistalovány srážkoměry.
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Vliv hospodářských zásahů na změnu v biologické rozmanitosti ve zvláště chráněných územích: Vliv různých managementových zásahů na vegetaci vřesovišť v Národním parku Podyjí III.
Mendelova zemědělská a lesnická fakulta v Brně, Ústav půdoznalství a mikrobiologie, Brno ; Masarykova univerzita v Brně, Přírodovědecká fakulta, katedra botaniky, Brno ; Botanický ústav AV ČR, Průhonice, pracoviště Brno ; Záhora, Jaroslav ; Chytrý, Milan ; Fabšičová, Martina ; Tůma, Ivan ; Holub, Petr ; Sedláková, Iva
Pokusy mají za cíl otestovat některé metody managementu vřesovišť: vypalování, pokosení drnů, pastvu. V této vegetační sezóně bylo sledováno celkem 38 trvalých ploch na vřesovištích v NP Podyjí. Od r. 2000 je také sledována dynamika mikrobiálních transformací dusíku v půdě, rychlost rozkladu opadu a efektivita využití N a P rostlinami.
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Diverzita vegetačních typů a recentních pylových spekter západních Sajan, Sibiř
Lučeničová, B. ; Kuneš, P. ; Jankovská, Vlasta ; Svobodová, Helena ; Chytrý, M. ; Danihelka, J. ; Ermakov, N. ; Hájek, M. ; Hájková, P. ; Havlová, Marie ; Kočí, M. ; Kubešová, S. ; Lustyk, P. ; Otýpková, Z. ; Roleček, J. ; Šmarda, P. ; Valachovič, M.
Comparison of recent pollen spectrum and the vegetation composition (Sayan, Siberia).
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