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Response of tree rings and NDVI of Central-European conifers to extreme climatic events
Mašek, Jiří ; Treml, Václav (advisor) ; Šilhán, Karel (referee) ; Piermattei, Alma (referee)
Terrestrial ecosystems, mainly forests are important sinks of atmospheric carbon with high year-to-year variability driven by moisture availability. Trees store carbon in various compartments of the biomass, namely in stems, roots, and leaves. In this doctoral thesis, I investigated climate-growth responses of stem biomass (represented by tree rings) and leaf biomass (represented by normalized difference vegetation index; NDVI) of Pinus sylvestris and Picea abies in temperate forests of Czechia. I was interested in (i) general climate-growth responses and specifically, in reactions to drought and (ii) topographical factors influencing these responses at various spatial scales. We demonstrated that climate-growth responses of both species' tree rings in the lowlands revealed a significant positive and negative influence of moisture and temperature, respectively, while in higher elevations the responses were opposite. At a landscape level, the topography of relief modulated responses of Pinus sylvestris tree rings, while at the large-scale level, the geographical position and elevation (temperature gradients) were the main factors for both species. Responses of NDVI were slightly weaker compared to tree rings and did not show the influence of topography at any scale probably because vegetation...
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Emerging Trends in Dendrochronology
Horáček, Tomáš ; Neuwirthová, Ludmila (referee) ; Mikulka, Jan (advisor)
Tato práce se zabývá popisem současných a experimentálních metod odběru vzorků pomocí presslerova nebozezu, výřezů z kmene, fotografie, rentgenu, počítačové tomografie a magnetické rezonance na poli dendrochronologického výzkumu. V práci jsou rozebírány destruktivní a nedesktruktivní metody odběru vzorků. Je také kladen důraz na původ vzorků: zdali je možno využít destruktivní metody nebo zdali je to nemožné jako v případě vzácných archeologických objektů. Dále popisuje standardní optometrickou metody a další experimentální metody fungujicí na principu kontranstního zpracování obrazu za účelem rozeznání letokruhů. V práci jsou také popsány různé druhy metod softwarového zpracovnání kde jako vstup slouží buď série dat nebo obraz letokruhů. Další rozdíly tvoří vymezené spektrum uvedených prací, některé práce se zaměřují na zpracování obrazu od píky tedy od pořízené fotografie až po hotové datovaní, některé však zajímá pouze úzký sektor dendrochronologie jako jsou například vady či špatně rozeznatelné letokruhy.
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Analýza tvorby dřeva buku lesního (Fagus sylvatica L.) na buněčné úrovni na výzkumné ploše Rájec - Holíkov
Porvalík, Radim
The content of this diploma thesis is the analysis of the formation of beech wood (Fagus sylvatica L.) at the cellular level, ie xylogenesis in the research area Rájec - Holíkov, which is located in the Drahanská Highlands. Specifically, this study focused on the activity of cells in the cambial zone and the differentiation of the new annual ring on individual days (DOY) during the 2016 growing season compared to 2015, when samples were taken (Trephor tool) regularly once a week using so-called micro-bore. Permanent microscopic slides were created from these, which were subsequently examined. The activity of cells in the cambial zone was started in 2015 and 2016 in the last week of April at a temperature of 8.3 ° C. The zone of secondary cell wall (SW) formation and gradual cell lignification was evident two weeks after the onset of postcambial growth until the end of August. After the application of the Gompertz function, the creation of a new annual ring took an average of 91 days in 2015 and its size was 1252.7 μm. The year 2016 was similar, the size was 1229.2 μm. The average time of creation of a new annual ring was higher, namely 117 days.
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A study of the behavior of selected metals in affected environments using an isotopic approach
Santos Baieta, Rafael ; Mihaljevič, Martin (advisor) ; Navrátil, Tomáš (referee) ; Tejnecký, Václav (referee)
Metals of anthropogenic origin have consistently polluted the environment. This thesis focuses mainly on highly contaminated soils or tree rings near mines and smelters in Sub-Saharan Africa. However, Portuguese soils were also assessed to study Pb isotopes in post-fire soils. The tracing capabilities of Pb isotopic ratios were employed to determine contamination sources and to evaluate the potential of pine trees as an environmental archive. Several analytical methods were applied, such as catalytic oxidation, Q-ICP-MS, ICP-OES, FEG-SEM/EDS, EPMA, XRD, etc. Soils near smelters located in three different cities [Kabwe (Pb-Zn), Luanshya (Cu, Co), and Selebi Phikwe (Ni, Pb)] exhibited concentrations of metals greatly exceeding those deemed acceptable by the competent authorities. In Kabwe, for example, concentrations of Pb exceeded 16 000 mg kg-1 . In all sites, contamination was shown to be significant only in the upper ±15 cm of soil. Samples of soils taken in remote locations were always clear of contamination. In Luanshya, metal(oid) bearing particles found in the soils were typically spherical and composed of rapidly cooled sulfides and oxides in the flue gas chambers of the local smelter. These were present only in the topsoil. The tree ring record of pine trees in Kabwe was shown to mimic the...
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Trends in tree-ring width of treeline trees along latitudinal gradient from subtropics to the Arctic.
Zborníková, Kateřina ; Treml, Václav (advisor) ; Mašek, Jiří (referee)
This bachelor thesis is interested in a tree ring of trees at the treeline from subtropics to the arctic and the main aim of this work is to find if there is a trend in the tree ring width at the treeline along the latidunial gradient. The work/thesis focuses on conifers. The data were obtained from International Tree-Ring Data Bank database, article searches and from the internal workplace database. A total of 9859 annual ring samples were obtained from 153 localities in Europe. Trees of the genus Pine (Pinus), Spruce (Picea) and Fir (Abies) were selected, which dominate the europeans ecotones of treeline. After removing the age trend, the regression of tree ring width and the latitude, were calculated. The results showed that in most cases the tree ring width decreases with higher latitude. However, a small number of tree ring samples from latitudes around 55ř north latitude adds to the uncertainty of this claim.
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Tree rings dendrochemistry near Cu smelter
Jarošíková, Alice ; Mihaljevič, Martin (advisor) ; Hojdová, Marie (referee)
Nkana smelter belonged to the main sources of contamination by trace elements (especially Cu and Co) in the area of African city Kitwe (Copperbelt, Zambia). The main objective of this study was to compare elemental and isotopic composition of Zambian soils and tree rings, and to investigate biogeochemical processes between plants and soils in contaminated and uncontaminated environment. Elemental composition (Cu, Co, Cr, Mn, Fe, Zn, Pb, Cd, Hg and Tl) and isotopic composition of Cu (63 Cu/65 Cu) were determined in soils and tree rings of pine trees (Pinus latteri, Pinus kesiya) using ICP-MS , AMA and MC ICP-MS. Our results demonstrated that soils and tree rings were both affected by mining and metallurgical activity. Increasing content of elements with depth is the result of the mobility of the elements in uncontaminated soil profile. Soil from contaminated site had the highest metal contents especially in the upper part of the soil profile as a result of continuous contribution of metallurgical components during long-term smelter operation. Fractionations of Cu isotopes in soils were caused primarily by interactions with plants. Concentration changes that some elements showed in the individual tree rings could be the effect of variable intensity of pollution in the area. In the case of Cu, however,...
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Tree-ring chronologies of Norway-spruce on west-east longitudinal gradient in the mountain ranges of central Europe
Ponocná, Tereza ; Treml, Václav (advisor) ; Kolář, Tomáš (referee) ; Vejpustková, Monika (referee)
The Earth's climate system has recently experienced substantial warming which likely impacts temperature-limited communities close to their distribution margins. The alpine treeline ecotone represents upper distributional limit of montane/subalpine forests. This biogeographic boundary relies mainly on decreasing temperature with increasing elevation. Surprisingly the response of treeline ecotone to ongoing warming has varied a lot and the reasons of this variability are poorly understood. The aim of this dissertation thesis is the assessment of growth trends and tree ring response of Norway spruce (Picea abies[L.] Karst.) to climatic oscillations at treelines and montane forests of East-Central Europe. This dissertation deals with both inter-regional and intra-regional (aspect, elevation) variability of tree growth. The presented results are based on an extensive data set of growth curves for almost 1400 trees. All study sites revealed close relationship between tree ring widths and growing season temperatures as well as the temperatures of October preceding to ring formation season. The main site-dependent differences in growth trends and temperature responses were attributed to elevation, the effect of aspect was relatively less significant. At treelines between the Krkonoše Mts. and Nízké Tatry...
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Arsenic in tree rings at As contaminated sites
Svoboda, Ondřej ; Mihaljevič, Martin (advisor) ; Vaněk, Aleš (referee)
Kutná Hora and its surrounding environment was affected by mining Ag, later Pb - Zn ore, lasting several centuries. As a result of mining, extreme concentrations of heavy metals and metalloids, especially As, in waters, soils and plants are. The aim of this work was to study the elemental composition of soils and tree rings, including processes between soil and plants on contaminated and uncontaminated area to describe biogeochemical processes between soil and plants. Elemental composition (V, Cr, Mn, Fe, Co, Cu, Zn, As, Cd, Sb, Tl, Pb) were determined in soils and tree rings of Scots pine (Pinus sylvestris) using ICP - MS. The measured concentrations of elements indicate contamination of soils and tree rings due to mining and metallurgical activities. The highest concentrations of As in soil (14 977 mg/kg) were found at contaminated site (Kaňk) at depth of 40 - 50 cm. This locality is situated on the heap, where waste from the mining and processing of ores are deposited, together with minerals and weathering products containing As. The uncontaminated area (Sukov) exhibited the maximum concentration of As in soils 124,38 mg/kg at a depth of 5 - 10 cm, due to the contamination by dust from the contamined sites. The highest concentrations of As in tree rings were determined in the contaminated area...
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Impact of being evergreen or deciduous on the wood anatomy of the trees in polar regions during the warm geological period : case study from Upper Cretaceous of the James Ross Island (Antarctic Peninsula)
Chernomorets, Oleksandra ; Sakala, Jakub (advisor) ; Gryc, Vladimír (referee)
Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...
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