Global ETD Search

351	Physicochemical studies regarding the utilization of wood- and peat-based fly ash Pesonen, J. (Janne) 11 October 2016 (has links) Abstract The main aim of the European Union’s waste legislation and the corresponding Finnish waste legislation is to reduce the production of waste. Further, the aims of the European Union’s growth strategy are to reduce the production of greenhouse gases, increase the use of renewable energy, and improve energy efficiency. According to the renewed Waste Tax Act, a waste tax has to be paid on all fly ashes that are deposited in landfills in Finland. A large amount of wood- and peat-based fly ashes are formed annually in Finland, and the amount is likely to increase in the future due to the increasing use of renewable energy. Previously, these ashes have mainly been deposited in industrial landfills, but the need to utilize the fly ashes has increased recently due to changes in waste legislation. In this thesis, several issues related to the utilization of wood- and peat-based fly ash were studied, with the general objective of improving the utilization potential of such ashes. As the first stage of this research, the suitability of willow ash for use as a fertilizer was studied. Willow ash would be well suited for use as a fertilizer due to its very high nutrient content. However, cadmium, a heavy metal, was found to be enriched in the ashes of the studied willow species. Due to this, special attention should be paid when choosing willow species for energy production. In the second stage of the research, the possibility of improving the strength development of wood- and peat-based fly ashes, as well as the possibility of stabilizing fly ash containing high amounts of heavy metals via the addition of cement and/or alkali activation, was investigated. Strength development was found to be dependent on the amount of reactive calcium and the ratio between that amount of reactive calcium and the sum of the reactive silicon, aluminum, and sulfur (Ca/(Si + Al + S)). The studied methods performed well in terms of stabilizing barium, copper, lead, and zinc. During the next stage, the effect of different chemical digestion methods, which are regulated by the Finnish waste legislation, on the utilization potential of fly ash was studied. The digestion method had a significant impact on the results of the potassium content analysis, which could affect the possibility of using fly ash as a fertilizer. As the final stage of the research, the co-granulation of ash with sewage sludge and lime was studied. From a technical point of view, the co-granulation was successful, although the compressive strength of the granules was low. Additionally, an insufficient nitrogen content was achieved with a sludge addition of 20-40 weight%. / Tiivistelmä Euroopan unionin jätelainsäädännön ja sitä vastaavan suomalaisen lainsäädännön tavoitteena on ehkäistä jätteiden muodostumista. Euroopan Unionin kasvustrategian tavoitteena on vähentää kasvihuonekaasupäästöjä, lisätä uusiutuvan energian käyttöä ja parantaa energiatehokkuutta. Uudistetun jäteverolain mukaan kaikista kaato-paikoille sijoitetuista lentotuhkista tulee Suomessa maksaa jäteveroa. Suomessa puu- ja turveperäisiä lentotuhkia muodostuu vuosittain suuria määriä ja määrä tulee vielä kasvamaan uusiutuvan energiankäytön lisääntyessä. Aiemmin nämä tuhkat ovat päätyneet pääasiassa läjitykseen teollisuuden kaatopaikoille, mutta muuttuneen jätelainsäädännön seurauksena tarve hyödyntää lentotuhkia on lisääntynyt. Tässä väitöstyössä tutkittiin puu- ja turveperäisten tuhkien hyödyntämiseen liittyviä kysymyksiä. Työn yleistavoitteena oli parantaa tuhkien hyödyntämis-mahdollisuuksia. Tutkimuksen ensimmäisessä vaiheessa tutkittiin pajutuhkan soveltuvuutta lannoitteeksi. Pajutuhka soveltuisi hyvin lannoitteeksi erittäin hyvien ravinne-pitoisuuksien ansiosta. Raskasmetalleista kadmiumin havaittiin kuitenkin rikastuvan tutkittujen pajulajien tuhkiin. Tähän tulisi kiinnittää erityishuomiota, kun pajulajeja valitaan energiantuotantoa varten. Tutkimuksen toisessa vaiheessa selvitettiin mahdollisuutta parantaa turpeen ja puun lentotuhkien lujittumista sekä raskasmetallipitoisen lentotuhkan stabiloimista sementtilisäyksen ja/tai alkaliaktivoinnin avulla. Lujuuden kehitys riippui reaktiivisen kalsiumin määrästä sekä reaktiivisen kalsiumin määrän ja reaktiivisten piin, alumiinin ja rikin määrien summan välisestä suhteesta (Ca/(Si + Al + S)). Tutkitut menetelmät toimivat hyvin bariumin, kuparin, lyijyn ja sinkin stabiloinnissa. Seuraavassa vaiheessa selvitettiin Suomen lainsäädännössä määritettyjen kemiallisten hajotusmenetelmien vaikutusta tuhkan hyödyntämispotentiaaliin. Hajotusmenetelmällä oli suuri merkitys kaliumin pitoisuutta määritettäessä, mikä voi vaikuttaa lentotuhkan hyödynnettävyyteen lannoitteena. Viimeisessä vaiheessa tutkittiin tuhkan yhteisrakeistusta lietteen ja kalkin kanssa. Teknisesti yhteisrakeistus onnistui hyvin, mutta rakeiden puristuslujuus oli alhainen. Lisäksi 20 - 40 paino% lietelisäyksellä ei rakeisiin saatu riittävän korkeaa typpipitoisuutta. ash fertilizers fertilizer legislation fly ash geopolymers granulation heavy metals peat ash recycled fuels sludge solubility stabilization willow wood ash geopolymeerit kierrätyspolttoaineet lannoitelainsäädäntö lentotuhka liete liukoisuus paju puutuhka rakeistus raskasmetallit stabilointi tuhkalannoitteet turvetuhka
352	Syncretisms for wind quintet and percussion: A study in combining organizational principles from Southeast Asian music with western stylistic elements. Seymour, John 05 1900 (has links) Syncretisms is an original composition scored for flute, oboe, clarinet, horn, bassoon, and marimba (2-mallet minimum, 4 recommended) with an optional percussion part requiring glockenspiel and chimes, and has an approximate duration of 6 min. 45. sec. The composition combines modern western tuning, timbre, and harmonic language with organizational principles identified in music from Southeast Asia (including music from cultures found in Thailand, Cambodia, Malaysia, and Indonesia). The accompanying paper describes each of these organizational principles, drawing on the work of scholars who have performed fieldwork, and describes the way in which each principle was employed in Syncretisms. The conclusion speculates on a method for comparing musical organizational systems cross-culturally. Southeast Asia marimba woodwind quintet Malaysia Thai Khmer Bali pin peat Java syncretic gamelan piphat Music -- East Asian influences.
353	Geovisualization of boreal peatland architecture in a three dimensional hydrogeological framework using ground penetrating radar and LiDAR at Mariana Lakes, Alberta, Canada Shulba, William Paul 07 June 2021 (has links) Communicating science in three-dimensional (3D) multimedia is an immersive and interactive way to explore scientific processes (Signals and Communication Technology, 2019). Geovisualization is an emerging 3D multimedia method for visual analysis, synthesis, and presentation of geospatial, geologic, and geophysical data (MacEachren & Kraak, 2001). There is an identified need to develop scientific communication tools to further understand boreal peatland evolution, hydrogeology, ecology, and geochemistry (Bubier et al., 2003) since the International Union of Conservation of Nature asserts that peatlands are among the most valuable ecosystems on Earth, critical for preserving global biodiversity, providing drinking water, minimising flood risk, preventing wildfire, and mitigating climate change (Hama et al., 2000). The intention of this thesis is to communicate a novel approach to geovisualize boreal peatland architecture using Light Detection and Ranging (LiDAR) and Ground Penetrating Radar (GPR). GPR and LiDAR have been used to create 3D subsurface geovisualizations for archaeology (Kenady et al., 2018; Schultz & Martin, 2011) and resource geology (Corradini et al., 2020; Koyan & Tronicke, 2020) although application to peatland hydrogeology is uncommon. Point-source hydrogeological and geochemical data were integrated with 3D geological models to estimate carbon and nitrogen storage in an archetypal boreal peatland near Mariana Lakes, Alberta. Peatland geometry resembled a shallow lake basin with depths greatest in fens (>10 m) and thinnest in bogs (<2 m). Hydraulic conductivity was only a few meters per year and vertical groundwater movement was limited. Sequestered carbon and nutrients increased with depth. The average concentration of dissolved ammonium was 3 grams per cubic metre of peat (g/m3), 5g/m3of Total Kjeldahl Nitrogen, 60g/m3 of dissolved organic carbon and 200g/m3 of dissolved inorganic carbon. Tritium detection from atmospheric atomic weapons radionuclide fallout revealed that in deeper anaerobic peat (catotelm), tritium was absent, signifying groundwater was older than 50 years and not mixed with meteoric waters. Fen catotelm channels are likely acting as gravity-driven hydraulic traps (Tóth, 1999). / Graduate geovisualization geography peatland boreal geology geography GPR LiDAR LeapFrog Seequent 3D modelling watersheds hydrology hydrogeology ecohydrology remote sensing Oilsands framework communication technology peat wetlands boreal carbon sequestration tritium fen bog nitrification Athabasca Oil Sands Region
354	Hydrologická funkce horských vrchovišť a vlastnosti rašelinných vod v pramenné oblasti Vydry / Hydrological function of peat bogs and peat water properties of the Vydra River headwaters Doležal, Tomáš January 2020 (has links) The retention potential of landscapes, along with the water regime of spring areas, are important hydrological topics of research, particularly in the current context of increasing extreme drought frequencies. The present work is focused on monitoring the mountain peat bogs, which, due to their overall frequency of occurrence in the spring area of the Vydra river, represent a significant constituent of the rainfall-runoff process of the area of interest. The specific hydropedological features of the organogenous soils (Histosol type soil) provide the high retention potential of the area, however, the influence of these soils on the runoff process is determined by complex physicogeographical factors. The general opinion on the hydrological function of the peat bogs has changed in recent years and the most important factor in the runoff formation in the mountain area of the Šumava Mts. is now thought to be the actual saturation of the headwater, which is predominantly composed of hydromorphic and organogenous soils. The organogenous soils are significant water reservoirs and have an important impact on the landscape. However, they may also intensify the extreme values of the watercourses during extreme precipitation events. The fundamental part of this work focuses on detailed observations of the...
355	Změny koncentrací organického uhlíku v povrchových vodách v pramenných oblastech / Changes of organic carbon in surface waters in headwater areas Špringerová, Pavla January 2019 (has links) Diploma thesis is focused on changes of organic carbon (OC) in surface waters in headwater areas. Thesis is in its theoretical part focused on the literature study of currently published research results of the issue. The important part is finding the possible causes of OC variability, especially landcover and soil environment. The practical part is devoted to research in experimental basins of KFGG, namely in the upper Vydra, Blanice and Rolava. The aim of this work is to clarify the relationships between organic matter concentrations and discharge rates regarding to hydrological extremes. Furthermore, the influence of river basin size and various landcover and variability of concentrations and relationship with other indicators of biogeochemism is studied. The relationship between OC and discharge rate is positive and in most river basins strong or very strong. The weakest relationship was monitored on the profiles with the highest proportion of peatlands in the river basin. In these catchments, the highest average concentrations of OC were determined in autumn, in catchments with the lower proportion of peatlands it is in summer. Analysis of rainfall-runoff events confirmed the positive relationship of OC and discharge. The lag time of the maximum OC concentration beyond the maximum discharge...
356	Conditions de l'accumulation du carbone dans une tourbière du Québec méridional : l'influence des facteurs autogènes et des contrôles allogènes Muller, Serge D. 09 1900 (has links) Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal. / Thèse de doctorat effectuée en cotutelle au Département de Géographie Université de Montréal et à l'Institut Méditerranéen d'Écologie et de Paléoécologie Université de Droit, d'Économie et de Sciences d'Aix-Marseille 111 / La tourbière de Mirabel (basses terres du St-Laurent, Québec méridional) a été étudiée dans le but de préciser l'influence exercée par les différents paramètres autogènes et allogènes sur l'accumulation postglaciaire du carbone. (l) Les dynamiques végétales régionales révèlent un contrôle climatique général, modulé localement par le contexte paléogéographique, la physiographie et les processus écologiques. (2) L'histoire postglaciaire du climat régional fut reconstituée par la méthode des analogues modernes, contrainte par les fluctuations du niveau du lac Hertel (Mont St-Hilaire). Les résultats obtenus témoignent d'un important réchauffement entre 13 000 et 11 000 cal. BP, d'un optimum thermique autour de 8000 cal. BP, et de deux périodes sèches (10 000-6500 et 5000-3000 cal. BP). (3) Les dynamiques postglaciaires internes de la tourbière furent indépendamment reconstituées en trois dimensions par l'analyse pluridisciplinaire de sept profils. Ces derniers montrent des successions végétales similaires, conformes au modèle de terrestrialisation, mais asynchrones. Ils témoignent en outre de conditions de surface très humides avant 6700 cal. BP, suivies de nombreuses fluctuations asynchrones sur l'ensemble du site. L'accumulation du carbone présente en revanche des tendances similaires dans tous les profils, caractérisées par de fortes accumulations avant 6200 cal. BP (moyennes de 7.1 à 19.1 gC.m .an'1) et de faibles accumulations depuis (moyennes de 2.7 à 6.3 gC.m'2.an ). (4) Les différentes conditions postglaciaires du développement de la tourbière sont confrontées. L'accumulation du carbone paraît avoir été essentiellement contrôlée par les interrelations entre la physiographie (alimentation minérotrophe initiale) et les processus autogènes, qui ont progressivement isolé la végétation tourbigène de la nappe phréatique. Notamment, ni le climat, ni les feux ne semblent avoir joué de rôle significatif. / Mirabel bog (St. Lawrence lowlands, southern Quebec) was studied with the aim to specify the influences exerted by the different autogenic and allogenic parameters on postglacial carbon accumulation. (1) Regional vegetation dynamics reveal a general climatic control, locally modified by the palaeogeographical context, physiography and ecological processes. (2) The postglacial history of the regional climate was reconstructed by the modem analogues method, constrained by the water level fluctuations of Lac Hertel (Mont St- Hilaire). Obtained results provide evidence for an important climate improvement between 13 000 and 11 000 cal. BP, a thermal optimum around 8000 cal. BP and two dry periods (10000-6500 and 5000-3000 cal. BP). (3) Postglacial internal dynamics were independently reconstmcted in three dimensions by the multidisciplinary analysis of seven profiles. They show similar plant successions, conforming to the terrestrialisation model but were asynchronous. They moreover attest the occurrence of very humid conditions prior to 6700 cal. BP, followed by numerous asynchronous fluctuations throughout the site. By contrast, carbon accumulation presents similar trends in all proiïles, characterised by high accumulation rates prior to 6200 cal. BP (averages from 7.1 to 19.1 gC.m .year ) and low rates since this date (averages from 2.7 to 6.3 gC.m'2.year-l). (4) The different postglacial conditions of peatland development arc coirfronted. Carbon accumulation appears to have been essentially controlled by the interplay between physiography (initial minerotrophic supply) and autogenic processes, which progressively isolated the peat-forming vegetation from groundwater. Notably, neither climate nor fire seem to have played a significant role. Paléoécologie Tourbière Facteurs autogènes et allogènes Végétation tourbigène Hydrologie interne Accumulation du carbone Physiographic Climat Niveaux lacustres Québec méridional Palaeoecology Peatland Autogenic and allogenic factors Peat-forming vegetation Internal hydrology Carbon accumulation Physiography Climate Lake-levels Southern Quebec Geography / Géographie (UMI : 0366)
357	Peatlands in Maputaland: Genesis, substrates and properties exemplified by the region of “Greater Manguzi” / A basis for recommendations on sustainable cultivation, conservation and restoration Gabriel, Marvin 17 April 2019 (has links) Moore in Südafrika sind wichtige, aber bedrohte Ökosysteme. Etwa 20.200 ha, zwei Drittel der südafrikanischen Moore, befinden sich auf der Maputaland Coastal Plain. Eukalyptusplantagen und gängige Anbaumethoden, die Dränung beinhalten, bedrohen die Existenz der Moore. Ein besseres Verständnis von Prozessen und Eigenschaften der Moore Maputalands ist dringend erforderlich, um effektive Schutzstrategien zu entwickeln. Diese Dissertation untersucht die Moorbildung in Maputaland aus einer bodenkundlichen Perspektive, um Voraussetzungen für effektive Schutzmaßnahmen und Renaturierungsmaßnahmen abzuleiten sowie Ratschläge für nachhaltigere Anbaumethoden auszuarbeiten. Per Großrestanalyse wurden Moor- und Torfbildungsprozesse untersucht. Auf Grundlage von 141 in Feldarbeit untersuchten Bodenprofilen wurden 15 unterschiedliche Moorsubstrate beschrieben und in genetische Substratgruppen sowie botanische Torftypen kategorisiert. Für diese Substrate wurden die folgenden physikalischen und chemischen Bodeneigenschaften bestimmt: Kohlenstoffgehalt, C/N Verhältnis, elektrische Leitfähigkeit, pH-Wert, Trockenrohdichte, Porenverteilung, gesättigte und ungesättigte hydraulische Leitfähigkeit sowie maximaler kapillarer Aufstieg. Zudem wurden die Auswirkungen von Degradierung auf die physischen und chemischen Eigenschaften der Moore untersucht. Hierfür wurden die eben benannten Kenngrößen für Substrate in verschiedenen Degradierungsstufen gemessen. Auf Grundlage der Veränderungen der Bodeneigenschaften werden die Verluste von Ökosystemfunktionen durch Degradierung diskutiert. Anhand der Häufigkeit der Substrattypen in den unterschiedlichen hydrogeomorphologischen Moortypen werden angepasste Empfehlungen für Schutz, Renaturierung und nachhaltigere landwirtschaftliche Nutzung der Moore erarbeitet, basierend auf den ermittelten Substrateigenschaften. Darüber hinaus werden auf Grundlage aktueller Klimaprognosen zukünftige Stresssituationen für die Moore durch den Klimawandel analysiert. / Peatlands in South Africa are important and threatened ecosystems. They are of great socio-ecological significance, as sources of freshwater, fertile land, material for construction, medicinal plants, habitat for specialised plants and animals, and as an attraction for ecotourists. Some 20.200 ha, about two thirds of South Africa’s peatlands, are located at the Maputaland Coastal Plain. Eucalyptus plantations and common cultivation practices which include drainage are threatening the existence of the peatlands. This dissertation investigates peatland formation in Maputaland from a soil-related point of view, in order to identify the requirements for effective conservation and restoration measures, as well as more sustainable cultivation practices. Insights into peat formation processes were obtained through a macrofossil analysis. Based on the field examination of 141 soil profiles, 15 different peatland substrates were described and categorised into genetic substrate groups, and botanical peat types. Mean values for the following physical and chemical properties were determined for each substrate: Carbon content, C/N ratio, electrical conductivity, pH-value, bulk density, pore size distribution, saturated hydraulic conductivity, unsaturated hydraulic conductivity and maximum capillary rise. Moreover, the effect of degradation on the physical and chemical properties of South African peatlands was explored. Therefore, the aforementioned properties were measured for substrates at different degrees of degradation. Based on the changes in the soil properties thus established, the loss of ecosystem functions through degradation is discussed. By considering the frequency of occurrence of the substrate types in different hydrogeomorphic peatland types, adapted implications for conservation, restoration and cultivation are derived. In addition, based on the actual projections of climate change, estimations about future stress on the peatlands were derived. AmaDobo uMzansi kwaNgwanase Makrofossilanalyse Hydrogenetische Moortypen Physikalische Bodeneigenschaften Substratklassifikation Südafrika Torfbildung Moordegradierung South Africa Hydrogenetic mire types Macrofossil analysis Peat formation Substrate classification Physical soil properties Peatland degradation 550 Geowissenschaften RS 74168 ZC 13174 ZC 13377 ddc:550
358	Bewirtschaftung von Niedermooren in der gemäßigten Klimazone: Treibhausgasemissionen und Rentabilität Rebhann, Marco Frank 17 August 2018 (has links) Niedermoore sind durch Grundwasser beeinflusste Standorte, in denen Torf gebildet wird oder oberflächig ansteht. Sie emittieren durch mikrobiologische Prozesse Treibhausgase (THG). Wird der Grundwasserstand gesenkt, steigen Kohlendioxid und Lachgas Emissionen, während bei einer Anhebung vermehrt Methan emittiert wird. Weltweit wird davon ausgegangen, dass Moore 5 % der anthropogen verursachten Emissionen verursachen. Um THG-Emissionen entgegenzuwirken, wird die Anhebung des Grundwasserstandes diskutiert. Dies führt durch eingeschränkte Befahrbarkeit und geringeres Kulturartenspektrum zu einer kaum gegebenen Wirtschaftlichkeit. Es fehlt ein Vergleich der THG-Emissionen und der Rentabilität der Bewirtschaftungssysteme verschiedener Landnutzungssysteme für Niedermoorstandorte der gemäßigten Klimazone. Die bodenbürtigen THG-Emissionen wurden mit einer Metaanalyse zu Veröffentlichungen von THG-Messungen in Niedermooren der gemäßigten Klimazone ermittelt. Ebenfalls wurden die bewirtschaftungsabhängigen Emissionen ermittelt und zu Gesamtemissionen zusammengefasst. Für den Vergleich der Rentabilität der Bewirtschaftungssysteme wurden Kosten und Erlöse berechnet. Abschließend wurden Treibhausgasvermeidungskosten abgeschätzt Bei zunehmender Landnutzungsintensität und größeren Grundwasserflurabstand nahmen die Gesamt-THG-Emissionen zu. Durch die Bewirtschaftung verursachte Emissionen spielten im Vergleich zu den bodenbürtigen Emissionen kaum eine Rolle. Zur THG-Einsparung und der Torferhaltung sollte die Bewirtschaftung extensiviert werden. Im Rentabilitätsvergleich erwiesen sich intensive, im Vergleich zu extensive Bewirtschaftungssysteme ohne Förderung als wirtschaftlich. Subventionen und Förderungen um torf- und klimaschonende Praktiken zu unterstützen, sind unverzichtbar. Mit dieser Arbeit wurde erstmalig für Niedermoore ein systematischer Überblick über die Gesamt-THG-Emissionen und die Rentabilität gängiger Bewirtschaftungssysteme verschiedener Landnutzungssysteme gegeben. / Fens are sites influenced by the groundwater where peat is formed in or located in the upper soil layer. They emit greenhouse gases (GHG) through microbiological processes in which the main influencing factor is the groundwater level. The lowering of the groundwater level increases carbon dioxide and dinitrogen monoxide emissions, while higher groundwater levels lead to methane emissions. It is assumed that fens cause 5% of global anthropogenic GHG emissions. In order to save peat and reduce GHG emissions, rewetting fens has been discussed and applied. This leads to low profitable land use due to limited trafficability and cultivation options. There is a lack of comparison of management systems in different land use systems regarding GHG emissions and profitability on fenlands in the temperate climate zone. The soil-borne GHG emissions for the land use systems were identified with a meta-analysis of published measurements of GHG emissions on fenlands in the temperate climate zone. The GHG emissions due to cultivation and possible land use changes were identified and summarized as the overall emissions. Costs and revenues were calculated for comparability purposes of profitability of management systems. GHG abatement costs were estimated too. Results indicated that overall GHG emissions increase with higher land use intensity and deeper groundwater level. Management induced GHG emissions are negligible compared to the soil-borne emissions. Fenlands should be extensified to save peats and reduce GHG emissions. The comparison of profitability showed that management systems of intensive land use systems, in contrast to extensive land use systems, with the low groundwater level are broadly profitable without subsidies. Subsidies and grants are indispensable to promote peat-saving and climate-friendly practices. This thesis provides a systematic overview of overall GHG emissions and profitability of common management systems of fenlands. Emissionen Treibhausgase CO2 CH4 N2O Niedermoor Torf organischer Boden Wiedervernässung Emissions Greenhouse Gases CO2 CH4 N2O Fen Peat Organic Soil Rewetting ZC 13174 ZD 63100 ddc:630
359	Multispectral imaging of Sphagnum canopies: measuring the spectral response of three indicator species to a fluctuating water table at Burns Bog Elves, Andrew 02 May 2022 (has links) Northern Canadian peatlands contain vast deposits of carbon. It is with growing urgency that we seek a better understanding of their assimilative capacity. Assimilative capacity and peat accumulation in raised bogs are linked to primary productivity of resident Sphagnum species. Understanding moisture-mediated photosynthesis of Sphagnum spp. is central to understanding peat production rates. The relationship between depth to water table fluctuation and spectral reflectance of Sphagnum moss was investigated using multispectral imaging at a recovering raised bog on the southwest coast of British Columbia, Canada. Burns Bog is a temperate oceanic ombrotrophic bog. Three ecohydrological indicator species of moss were chosen for monitoring: S. capillifolium, S. papillosum, and S. cuspidatum. Three spectral vegetation indices (SVIs) were used to characterize Sphagnum productivity: the normalized difference vegetation index 660, the chlorophyll index, and the photochemical reflectance index. In terms of spectral sensitivity and the appropriateness of SVIs to species and field setting, we found better performance for the normalized difference vegetation index 660 in the discrimination of moisture mediated species-specific reflectance signals. The role that spatiotemporal scale and spectral mixing can have on reflectance signal fidelity was tested. We were specifically interested in the relationship between changes in the local water table and Sphagnum reflectance response, and whether shifting between close spatial scales can affect the statistical strength of this relationship. We found a loss of statistical significance when shifting from the species-specific cm2 scale to the spectrally mixed dm2 scale. This spatiospectral uncoupling of the moisture mediated reflectance signal has implications for the accuracy and reliability of upscaling from plot based measurements. In terms of species-specific moisture mediated reflectance signals, we were able to effectively discriminate between the three indicator species of Sphagnum along the hummock-to-hollow gradient. We were also able to confirm Sphagnum productivity and growth outside of the vascular growing season, establishing clear patterns of reflectance correlated with changes in the local moisture regime. The strongest relationships for moisture mediated Sphagnum productivity were found in the hummock forming species S. capillifolium. Each indicator Sphagnum spp. of peat has distinct functional traits adapted to its preferred position along the ecohydrological gradient. We also discovered moisture mediated and species-specific reflectance phenologies. These phenospectral characteristics of Sphagnum can inform future monitoring work, including the creation of a regionally specific phenospectral library. It’s recommended that further close scale multispectral monitoring be carried out incorporating more species of moss, as well as invasive and upland species of concern. Pervasive vascular reflectance bias in remote sensing products has implications for the reliability of peatland modelling. Avoiding vascular bias, targeted spectral monitoring of Sphagnum indicator species provides a more reliable measure for the modelling of peatland productivity and carbon assimilation estimates. / Graduate peatland peatland restoration peatland monitoring peatland modelling peat peat moss multispectral multispectral imaging multicamera array multitemporal multiple linear regression linear mixed effects Sphagnum sphagna Sphagnum capillifolium Sphagnum papillosum Sphagnum cuspidatum spatiospectral uncoupling near-sensing remote sensing phenospectral phenology phenologies phenospectral bias phenospectral libraries carbon assimilation carbon dioxide carbon dynamics carbon emissions carbon geographies carbon mineralization carbon sequestration carbon source carbon sink carbon storage irrecoverable carbon climate forcing methane Ecological Restoration restoration ecology ecohydrology ecohydrological restoration hydrology ecohydrological gradients ecological integrity reflectance nature based solutions ombrotrophic moss raised peatland mires mires photochemical reflectance index normalized difference vegetation index chlorophyll index climate change climate forcing climate envelope climatope nonvascular vascular bias plant functional type plant functional types structure equation models spectral vegetation indices hummock hollow acrotelm catotelm diplotelmic biocrusts organic soil periodicity moisture deficit senescence rejuvenescence productivity photosynthesis light use efficiency photosynthetic function photosynthetically active radiation water table hydrology rewetting depth to water table landscape change landscape degradation peat subsidence Burns Bog
360	Tvorba odtoku a jeho dynamika v pramenné oblasti Otavy / Streamflow generation process and its dynamics in the Otava river headwaters Kocum, Jan January 2012 (has links) In context of catastrophic floods and extreme droughts in recent years there is an urgent need of solving of issues dealing with protection against hydrological extremes, not using just classical engineering methods but also untraditional practices. There is a new protection strategy focusing on gradual increase of river catchment retention capacity including its headwater regions. All of the issues related to various possibilities and measures leading to river headstream areas retention capacity increase should be discussed by experts in various fields taking into account objectives and priorities of a supra-regional, regional and local significance. Natural runoff process is affected by man already by its birth, thus in headwaters where numerous procedures related to runoff retardation and water retention increase in headstream areas could be realized. Suitable conditions for the research realization at present is related to the Otava River headwaters (sw. Czechia) representing the core zone of a number of extreme runoff events and with high heterogeneity in the terms of physical-geographic and socio-economic aspects. To understand and clarify the runoff generation process and the effect of various physical-geographic factors on its dynamics, the detailed analyses of runoff regime in chosen...

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