The Sphagnum bogs of the Tofino-Ucluelet area of the western coast of Vancouver Island were studied from vegetational, edaphic, and historical aspects. An integrated approach to these three aspects was attempted in order to give in a relatively limited time as complete a picture as possible of the bog ecosystem. The bog vegetation was studied on 110 sample plots using analytical and synthetic methods of the Zurich-Montpellier school of phytosociology. Ten different vegetation types were described and characterized, nine belonging to the bog ecosystem and one to the surrounding scrub forest. The nine bog vegetation types consist of five distinct associations and one association composed of five variants. The vegetation types studied are summarized below, in order of increasing floristic complexity. Low moor bog associations: 1. Caricetura pluriflorae (Carex plurlflora association) 2. Scirpeto-Sphagnetum mendoclnl (Sclrpus caespitosus - Sphagnum mendocinum association) 3. Oxycocceto-Sphagnetum papillosi (Oxycoccus quadripetalus - Sphagnum papillosum association) High moor bog association: 4. Ledeto-Sphagnetum caplllacei (Ledum groenlandicum - Sphagnum capillaceum association) Peripheral bog associations: (Bog-forest transition) 5. Pineto-Sphagnetum capillacei (Pinus contorta - Sphagnum capillaceum association) a. Pineto-Sphagnetum capillacei sphagnosum papillosi (Pinus contorta hummock variant) b. Pineto-Sphagnetum capillacei myricosum galis (Myrica gale variant) c. Pineto-Sphagnetum capillacei chamaecyparosum nootkatensis (Chamaecyparis nootkatensis variant) Secondary succession variants established after fire: d. Pineto-Sphagnetum capillacei vacciniosum vitis-idaeae (Vaccinium vltis-idaea variant) e. Pineto-Sphagnetum capillacei vacciniosum parvifolii (Vaccinium parvifollum variant) Scrub forest association surrounding bogs: 6. Pineto-Chamaecypareto-Sphagnetum recurvi (Pinus contorta - Chamaecyparis nootkatensis - Sphagnum fecurvum association) (Bog forest) Edaphic considerations were limited to the analysis of soils from representative sample plots of each association and variant. Soils were analyzed for available cations, including Ca⁺⁺, Mg⁺⁺, Na⁺, K⁺, adsorbed phosphate, total nitrogen, cation exchange capacity, percent base saturation pH, and soil moisture. The results of the soil analyses were wherever possible correlated with trends in the development of plant associations. Climatic factors were regarded as constant over so limited an area as the one under study. Historical considerations included a pollen analysis from a representative core in the center of the major study bog, and a radiocarbon dating to determine the age of a representative bog. The results of the pollen analysis appeared to confirm previous ideas that the bog did not develop from a lake, but rather it developed from a wet seepage forest habitat. The radiocarbon dating indicated the age of the bog at only 390± 90 years B.P., thus explaining partially the apparent very juvenile phase of the bogs of the area. The general hypothesis is suggested that the distribution of the bog plant associations is primarily dependent upon a complex of environmental factors that are dependent upon topography. / Science, Faculty of / Botany, Department of / Graduate

No description available.

No description available.

The purpose of this report was to investigate which of the two products peat and granular sulphur that generates the least greenhouse gas emissions. The study was performed by doing a comparative Life Cycle Assessment (LCA) on the two different products. To perform the LCA, a standard from the Swedish Standards Institute was used. Data to put into the calculation was obtained from both Umeå Energi, their contractors and different internet-sources. The data was then multiplied with specific emission factors to get the total emission of greenhouse gases, expressed as carbon dioxide equivalents. Since peat is considered both a fossil energy source and a renewable energy source two calculations were made in the case of peat production. Results showed that granular sulphur generated the least emissions (23.0), peat classified as a renewable energy source second most emissions (71.5) and peat classified as a fossil energy source by far the most emissions (978.2). The conclusion to be made by this study is that if only the emission of greenhouse gases are important when choosing a product, granular sulphur should be used. Key words: peat, greenhouse gases, LCA, sulphur.

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No description available.

UK uplands preserve a rich history of human inhabitation and environmental change through standing monuments, archaeological sites, and within peat deposits. Palaeoenvironmental remains within peat can be used to reconstruct environmental histories throughout the Holocene. Small mires in varied topographic locations can allow detailed local landscape reconstruction, setting archaeological sites in environmental context, or building up a picture of the mosaic of changing landscapes through time. Recent moves towards assessing the ecosystem services provided by different landscapes mean that, to make a case for preserving upland peatlands for the palaeoenvironmental remains they preserve, we must be able to demonstrate their archaeological potential or value. This project investigated methods for identifying the extent of this ‘hidden’ resource, as well for assessing its current condition and historic environment value, through the case study of valley, spring and soligenous mires on Exmoor. The lack of known archaeological or material culture remains from upland peatlands in the UK and on Exmoor means that the project focussed solely on the palaeoenvironmental resource. The methods used combined desk-based survey and spatially-extensive walkover survey to assess the overall extent and condition of the palaeoenvironmental resource in mires across Exmoor. Alongside this, a site-based programme of water-table monitoring and coring was undertaken to look at the effects of recent land management practices on the condition of this resource. The results demonstrated that walkover survey and peat depth probing were necessary to define the spatial extent and depth of mires, and assess mire condition. A standardised key was developed to allow the baseline mire condition survey to be repeated. The site-based study demonstrated the negative impact of water-table draw-down on the condition of palaeoenvironmental remains. However, it also demonstrated that a multiproxy approach is necessary to allow the complex palimpsest of the effects of human impact, climate change, and recent damage to mires, to be disentangled. The results of both levels of survey fed into the development of a flexible heritage valuation system for the palaeoenvironmental resource, which highlighted mires with high-potential for future investigation, whilst indicating mires which will require management intervention to prevent further losses to the resource. The datasets provided by this project will be used to identify palaeoenvironmental sampling locations for future archaeological investigations and allow heritage managers to make active contributions to the selection of sites for mire restoration. It provides a baseline survey against which future mire condition monitoring can be compared and which can be extended to other regions. It also offers a dataset against which to test or ‘ground-truth’ new methods for identifying the extent and condition of peatlands using remote-sensed data.

The use of critical loads of acidity to quantify damage to sensitive components of terrestrial and aquatic ecosystems has developed rapidly over the last decade. While much work has focused on defining damage to forested ecosystems, surface waters and groundwaters, there has been little work done on defining critical loads of acidity for ombrotrophic and minerotrophic peat. This thesis presents a modelling approach to quantify damage to ombrotrophic peat ecosystems, since such damage can result in a decline in both surface water quality and the ability of peat to act as an absorbent to aerial pollutants. Initial investigations were concerned with the factors which could be included in investigations of critical loads of N and acidity to the surface organic horizons of forest and moorland soils. The modelling approach was then developed from a series of laboratory-based simulation experiments to investigate the effect of contents of H&'43 , Ca2&'43 and Mg2&'43 in rainfall upon the chemistry of the peat ion exchange complex. The basic tenet of the modelling approach was that ion exchange equilibria for peat is rapid, mineral input to the surface of ombrotrophic peat from mineral weathering is negligible and that atmospheric inputs of wet and dry deposition will dominate the peat chemistry. These simulation experiments provided peat pH values resulting from equilibration with the simulated rainfall. By combining these with databases of atmospheric depositon for the U.K., critical loads of acidity and the present day peat pH were calculated and mapped. The critical load values for peat thus obtained were incorporated in the U.K. Critical Load mapping program, which was used to support the on-going European negotiations of emission reduction within the United Nations Convention on Long-range Transboundary Air Pollution (U.N. E.C.E. C.L.T.A.P.).

Orientador: André Henrique Rosa / Banca: Ana Teresa Lombardi / Banca: Elisabete Alves Pereira / Banca: Marcelo Luiz Simões / Banca: Ademir dos Santos / Resumo: As interações entre interferentes endócrinos (IE), bisfenol A, estrona, 17β- estradiol, e amostras de sedimentos e turfas tropicais foram estudadas em diferentes condições de pH, tempo e quantidade de amostra, bem como estudos de sorção e dessorção utilizando colunas recheadas com turfas. Ainda foram realizados experimentos de fitorremediação de bisfenol A, linuron e 17α- etinilestradiol de diferentes ambientes utilizando as espécies Lolium perenne e Raphanus sativus. Os dados obtidos a partir dos experimentos com sedimentos mostraram uma melhor interação IE-sedimento ocorreu em valores menores de pH, enquanto os com turfas foram observados em pH 6. Uma cinética lenta foi observada através do modelo cinético de pseudo-segunda ordem que descreveu bem as interações dos IE com sedimentos e turfas (r> 0,99). A partir das isotermas de Langmuir e Freundlich, os valores dos coeficientes n e b, revelaram que as interações IE-turfa são reversíveis, exceto nos experimentos realizados com a amostra coletada em Santo Amaro das Brotas e estrona e 17α-etinilestradiol, onde os valores de b foram, respectivamente, 1,50 e 13,94. Os resultados de sorção em coluna mostraram que as turfas podem ser utilizadas como alternativa para a remoção destes compostos dos sistemas aquáticos onde tanto a sorção quanto a dessorção foram superiores a 75 %. Os experimentos de fitorremediação mostraram que a espécie Raphanus sativus foi mais eficiente na remoção dos IE, principalmente em valores de concentração dos IE mais baixos, a germinação das duas espécies foram menores quando utilizada a água do rio Morelli como meio. Estudos desta natureza proporcionam uma melhor compreensão da mobilidade, transporte e/ou reatividade destes contaminantes em sistemas aquáticos, onde a disponibilidade dos IE pode estar relacionada com a presença de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Interactions between endocrine disruptors (ED), bisphenol A, estrone, 17β- estradiol, and samples of sediments and tropical peat were studied under different conditions of pH, time and amount of samples, and sorption and desorption studies using packed columns with peat. Although, experiments of phytoremediation of bisphenol A, 17α-ethinylestradiol and linuron were conducted in different environments using Lolium perenne and Raphanus sativus species. Data obtained from the experiments showed a better EDsediment interactions at pH 3, however a better ED-peat interactions was observed at pH 6. Slow kinetics was observed by the kinetic model of pseudosecond order which described well the interactions between IE and sediments and peat samples (r> 0.99). From the Langmuir and Freundlich isotherms, the coefficients n and b values, revealed that the ED-peat interactions are reversible, except in experiments with the sample collected in Santo Amaro das Brotas and estrone and 17α-ethinylestradiol, where the values of b were respectively 1.50 and 13.94. The column sorption results showed that peat may be used as an alternative for the removal of these compounds from aquatic systems where sorption and desorption was higher than 75%. The phytoremediation experiments showed that Raphanus sativus specie was more efficient in the removal of ED, especially in lower concentrations of ED. Lower germination of both species were observed in all experiments with water from Morelli river. Studies of this nature provide a better understanding of mobility, routing and / or reactivity of these contaminants in aquatic systems, where the availability of ED can be related to the presence of organic material. And still shows that both peat and phytoremediation, natural and economically attractive methods, can be... (Complete abstract click electronic access below) / Doutor

This thesis examines whether short term (one to three weeks) microbial sensitivity to temperature and carbon (C) inputs can be predicted from peat characteristics driven by nutrient gradients. The aim was to determine if relationships exist between peat macronutrient (C, nitrogen (N), phosphorus (P)) concentrations, microbial community composition and the microbial response to changes in temperature and C supply. The focus of this thesis was on using peat macronutrient concentrations as explanatory variables as this is a metric which is easy to define and measure consistently, unlike other factors such as peat C quality and availability of nutrients. It was observed that, over short timescales, microbial respiration rates in peat soils increased in response to warming, nutrient (N and P) additions and increased labile C supply. In the first two experimental chapters it was found that peat respiration was sensitive to temperature, with increases of 10°C shown to increase microbial CO2 production by factors of 2.8 to 4.4. In the final two experimental chapters priming effects in peat were examined with C additions found to stimulate microbial activity and increases in peat derived CO2 flux, which could be attributed to priming. Despite the wide variation in nutrient concentrations in the peat soils examined no clear relationships between peat nutrient properties (total and available concentrations) and the magnitude of the microbial responses were observed.