Compared to upland areas and Scotland, the Holocene vegetational history of lowland England is poorly known. This is particularly the case for the region of Holdemess, eastern Yorkshire, where only a low number of poor temporal resolution pollen diagrams have been published, none of which include analysis of microscopic charcoal content. The records are also largely undated and as a result reliable correlation between sites is not possible, and the timings of the key vegetation changes recorded in the data remain unknown. In this study, high resolution pollen and charcoal records were produced from four small (24 ha) infilled basins located within central Holderness. Complementary techniques of percentage loss-on-ignition and pollen preservation analysis were also employed, and a comprehensive radiocarbon-dating programme was undertaken to provide a secure chronological framework. The palaeoecological records produced provide a high temporal resolution reconstruction of the Holocene development of central Holderness, particularly during the Early-Mid Holocene, and allow consideration of the changing roles that ecological interactions, climate, and human influence have played in determining the Holocene vegetational composition of the region. A number of significant landscape-scale disturbances of inferred anthropogenic origin were identified from ca 9290 BP onwards and shown to vary significantly in timing, duration and character between sites. It is proposed that this palaeoecological data can be used to supplement the poor archaeological record of the area. Several key issues including the role of climatic instability in determining vegetational composition during the Early Holocene, the interpretation of incidences of cereal-type pollen, the use of the charcoal record as a proxy indicator of human activity, and the use of pollen preservation analysis as an interpretational tool are also considered.

Pollen and charcoal percentage and concentration analyses have been conducted upon several upland peat profiles of late Flandrian II and early Flandrian III age at North Gill, North York Moors, where earlier research had proven recurrent major pre Elm Decline woodland disturbance, supported in one profile by radiocarbon dating. Fine temporal resolution pollen analysis (FRPA) involving the use of contiguous millimetre sampling was applied to Flandrian II disturbance phases at five of the North Gill profiles. At North Gill 1A a further phase of disturbance near the end of Flandrian II was examined using FRPA to study evidence of pre Elm Decline agricultural activity, and at this profile both the horizontal and vertical resolution limits of the technique were tested by progressively finer sub-sampling. The millimetre level FRPA analyses showed that each of the examined pre Elm Decline disturbance phases was an aggregate feature, composed of a number of smaller sub-phases, the ecological effects of which in terms of spatially-precise woodland successions and community structures were assessed and contrasted. Inter-profile spatial comparison of the ecology of woodland disturbances has been made at both FRPA and conventional scales of temporal resolution. FRPA study of the late Flandrian II disturbance phase at North Gill 1A showed that cereal cultivation had occurred prior to the Elm Decline as part of a multi-phase period of agricultural land-use activity. The high resolution spatial and temporal data from North Gill have shown FRPA to be a most sensitive palaeoecological technique, and are discussed in relation to the effects of disturbance upon mire and woodland ecosystems, Mesolithic land-use, pre Elm Decline cereal cultivation and early Neolithic land-use.

Thesis (M.Sc.)--University of Western Australia, 2006.

Orientador: Edson Luiz Furtado / Banca: Waldir Cintra de Jesus Junior / Banca: Cláudio Angeli Sansigolo / Resumo: As plantações de eucalipto no Brasil vêm crescendo significativamente ao longo dos anos. Minas Gerais tem 29% da área plantada e esta madeira é destinada quase exclusivamente ao pólo siderúrgico na produção de ferro gusa a partir do carvão vegetal. Portanto, o crescimento da área plantada aliada as condições climáticas, propicia o aparecimento e multiplicação de pragas e doenças. Uma das doenças que vem se tornando de importância econômica é a murcha de Ceratocystis, causada pelo fungo Ceratocystis fimbriata, que é um patógeno típico de xilema secundário. Esta doença foi monitorada no período de 2005 a 2011, em 3 municípios de Minas Gerais, com os dados de incidência da doença no campo foi feito o estudo epidemiológico no espaço e no tempo. A evolução da doença no tempo foi melhor explicada pelo modelo monomolecular, com um coeficiente de regressão superior a 90%. A distribuição da doença ocorre de forma agregada e na linha, podendo-se inferir que as mudas foram levadas contaminadas para o campo, e isto pode ter ocorrido no processo de propagação clonal. Analisando os dados climáticos do banco de dados do WORLDCLIM e o software DIVA-GIS, gerou-se um mapa de favorabilidade da doença para o estado de Minas Gerais, concluindo que as áreas dos municípios estudados são de alta favorabilidade à doença, portanto, o uso de material genético resistente é imprescindível para garantir a produtividade das plantações florestais. Foi analisada a interferência da doença na quantidade e qualidade da madeira e do carvão vegetal, concluindo que este fungo ocasiona perdas significativas de em média R$ 7.000/ha na cadeia produtiva do carvão vegetal / Abstract: Eucalyptus plantations in Brazil have been growing significantly over the years. Minas Gerais has 29% of the planted area, and this wood is destined almost exclusively to the steel pole in the production of pig iron from charcoal. Therefore, the growth of the planted area combined with the climatic conditions, allows the emergence and proliferation of pests and diseases. A disease that is becoming economically important is the Ceratocystis wilt, caused by the fungus Ceratocystis fimbriata, a pathogen that is typical of xylem. This disease was monitored in the period of 2005 to 2011 in three towns in Minas Gerais, having an epidemiological study in space and time been done with the data on incidence of the disease in the field. Disease progression in time is best explained by the monomolecular model with a regression coefficient greater than 90%. As the spread of the disease occurs in the aggregate and on the line (in an aggregated and linear way), it can be inferred that the seedlings were taken to the field already contaminated, and this may have occurred in the process of clonal propagation. Analysing climatic data from the database and software WORLDCLIM DIVA-GIS, a map of favorability was generated about the disease in the state of Minas Gerais, concluding that the areas of the cities studied are highly favorable to the disease, therefore, the use of resistant material is essential to ensure the productivity of forest plantations. We analyzed the influence of the disease in the quantity and quality of wood and charcoal production, concluding that this fungus causes significant losses in average US$ 2.800,00 in this chain / Mestre

Made available in DSpace on 2014-06-11T19:30:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-11-19Bitstream added on 2014-06-13T18:40:23Z : No. of bitstreams: 1 fernandes_bv_me_botfca.pdf: 1478284 bytes, checksum: 76662832a991b0c848813c6dd719d42a (MD5) / As plantações de eucalipto no Brasil vêm crescendo significativamente ao longo dos anos. Minas Gerais tem 29% da área plantada e esta madeira é destinada quase exclusivamente ao pólo siderúrgico na produção de ferro gusa a partir do carvão vegetal. Portanto, o crescimento da área plantada aliada as condições climáticas, propicia o aparecimento e multiplicação de pragas e doenças. Uma das doenças que vem se tornando de importância econômica é a murcha de Ceratocystis, causada pelo fungo Ceratocystis fimbriata, que é um patógeno típico de xilema secundário. Esta doença foi monitorada no período de 2005 a 2011, em 3 municípios de Minas Gerais, com os dados de incidência da doença no campo foi feito o estudo epidemiológico no espaço e no tempo. A evolução da doença no tempo foi melhor explicada pelo modelo monomolecular, com um coeficiente de regressão superior a 90%. A distribuição da doença ocorre de forma agregada e na linha, podendo-se inferir que as mudas foram levadas contaminadas para o campo, e isto pode ter ocorrido no processo de propagação clonal. Analisando os dados climáticos do banco de dados do WORLDCLIM e o software DIVA-GIS, gerou-se um mapa de favorabilidade da doença para o estado de Minas Gerais, concluindo que as áreas dos municípios estudados são de alta favorabilidade à doença, portanto, o uso de material genético resistente é imprescindível para garantir a produtividade das plantações florestais. Foi analisada a interferência da doença na quantidade e qualidade da madeira e do carvão vegetal, concluindo que este fungo ocasiona perdas significativas de em média R$ 7.000/ha na cadeia produtiva do carvão vegetal / Eucalyptus plantations in Brazil have been growing significantly over the years. Minas Gerais has 29% of the planted area, and this wood is destined almost exclusively to the steel pole in the production of pig iron from charcoal. Therefore, the growth of the planted area combined with the climatic conditions, allows the emergence and proliferation of pests and diseases. A disease that is becoming economically important is the Ceratocystis wilt, caused by the fungus Ceratocystis fimbriata, a pathogen that is typical of xylem. This disease was monitored in the period of 2005 to 2011 in three towns in Minas Gerais, having an epidemiological study in space and time been done with the data on incidence of the disease in the field. Disease progression in time is best explained by the monomolecular model with a regression coefficient greater than 90%. As the spread of the disease occurs in the aggregate and on the line (in an aggregated and linear way), it can be inferred that the seedlings were taken to the field already contaminated, and this may have occurred in the process of clonal propagation. Analysing climatic data from the database and software WORLDCLIM DIVA-GIS, a map of favorability was generated about the disease in the state of Minas Gerais, concluding that the areas of the cities studied are highly favorable to the disease, therefore, the use of resistant material is essential to ensure the productivity of forest plantations. We analyzed the influence of the disease in the quantity and quality of wood and charcoal production, concluding that this fungus causes significant losses in average US$ 2.800,00 in this chain

No description available.

No description available.

Pioneering work performed by Rosalind Franklin over half a century ago provided the first structural models of two distinct carbon types: those that become graphitic during carbonization at high temperatures, and those that do not. Moreover it is known that certain properties of carbonaceous materials including combustion, surface area, electrical resistivity, and catalytic properties are influenced by mineral impurities. The nature of this division in biocarbon structure and the known effects of minerals on carbon properties have led to this work; three principal topics were addressed; (1) the investigation of the solid state structure of biocarbons derived from various biomass feedstocks, (2) the removal of inorganic minerals from biomass, and (3) the investigation of biocarbon electronic structure subsequent to doping with select inorganic minerals. Charcoals and carbonized charcoals (i.e. biocarbons) were prepared from a wide variety of biomass substrates, including pure sugars containing 5- and 6-membered rings with furanose and pyranose configurations, lignin, agricultural residues (corncob and nut shells) and a hard wood. These biocarbons were subject to proximate and elemental analysis, gas sorption analysis, and analysis by ICP-MS, SEM, XRD, ESR, 13C CPMAS NMR, and MALDI-TOF MS. All the carbonized charcoals contained oxygen heteroatoms, had high surface areas, and were excellent conductors of electricity. Doping the biocarbon with boron or phosphorus resulted in a slight improvement in its electrical conductivity. The XRD analysis indicated that the carbonized charcoals possess an aromaticity of about 71% that results from graphite crystallites with an average size of about 20 . The NMR analysis confirmed the highly aromatic content of the carbonized charcoals. The ESR signals indicated two major types of carbon-centered organic radicals. A number of techniques employed highlighted differences between carbonized charcoals and synthetic graphite but none more so than MALDI-TOF spectrometry. The biocarbons contained readily desorbed discrete ions with m/z values of 701, 685, 465, 453, 429, and 317. All of the above findings were used to develop a model for the structure of carbonized charcoal that is consistent with the biocarbon's oxygen content, microporosity and surface area, electrical conductivity, radical content, and its MALDI-TOF spectra. The removal of inorganic mineral constituents from various biomass feedstocks was achieved via simple washing/soaking techniques using two different aqueous media; deionized water and citric acid. The most effective and consistent demineralization treatment for removing minerals from biomass involved a hot 0.1 molL-1 citric acid percolation treatment, ca. 67% of inorganic mineral matter was removed. Mineral matter at the levels present in typical biomass derived charcoals and carbons had no significant influence upon the surface area or the electrical resistivity in carbonaceous materials after high heat treatment (950 C).

The thesis presents systematical study and taphonomical evaluation of fusite wood specimens collected in the middle bench of the main lignite seam in the Bilina mine. In the introduction part, there are a general characteristic of the Most Basin and its geological setting with respect to the main lignite seam. Consequently, the charcoal is described in detail. Generally, the charcoaled wood, which was produced during wildfires in the Tertiary forests, shows well preserved anatomical details. The final part resumes systematics and taphonomy of the charcoal specimens collected by the author.

No description available.