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Natural regeneration on clearcuts at the lower limit of the mountain hemlock zoneKlinka, Karel January 1997 (has links)
The Mountain Hemlock (MH) zone includes all subalpine forests along British Columbia’s coast. It occurs at elevations where most precipitation falls as snow and the growing season is less than 4 months long. The zone includes the continuous
forest of the forested subzones and the tree islands of the parkland subzones (Figure 1). Old-growth stands are populated by mountain hemlock, Pacific silver fir, and Alaska
yellow-cedar, and are among the least-disturbed ecosystems in the world. Canopy trees grow slowly and are commonly older than 600 years, while some Alaska yellow-cedars may be up to 2000 years old.
Early regeneration failures followed slashburning and the planting of unsuitable species. Currently, the most successful and feasible option for reforesting cutovers is natural
regeneration with a mix of the three main tree species, but uncertainties remain about the temporal and spatial pattern of regeneration, changes in species composition, and the time
required for stand establishment after cutting. Our study addressed these concerns by examining regeneration patterns on 6 sites that were clearcut 11-12 years prior to sampling and left to regenerate naturally. The sites were located at the lower
limits of the zone in the Tetrahedron Range, near Sechelt, at elevations from 1060-1100m.
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Fundamental understanding of the biochemical conversion of Buddleja davidii to fermentable sugarsHallac, Bassem Bishara 29 March 2011 (has links)
Lignocellulosic bioethanol is currently being explored as a substitution to fossil fuels. Many lignocellulosic materials are being examined but the importance is to find those with attractive agro-energy features. Producing lignocellulosic ethanol is challenging because lignocellulosic biomass is resistant to chemical and biological degradation. To reduce biomass recalcitrance, a pretreatment stage is required. Pretreatment is considered to be the most intensive operating/operating cost component of cellulosic ethanol production. Therefore, research is heavily focused on understanding the effect of pretreatment technologies on the fundamental characteristics of lignocellulosic biomass.
The first study in the thesis investigates Buddleja davidii as a potential biomass source for bioethanol production. The work focuses on the determination of ash, extractives, lignin, hemicellulose, and cellulose content in this plant, as well as detailed elucidation of the chemical structures of both lignin and cellulose by NMR spectroscopy. The study showed that B. davidii has several unique agro-energy features as well as some undesired characteristics.
The second study presents research on the ethanol organosolv pretreatment (EOP) of B. davidii and its ability to produce enzymatically hydrolysable substrates. It was concluded that the removal of hemicellulose, delignification, reduction in the degree of polymerization (DP) of cellulose, and the conversion of crystalline cellulose dimorphs (Iα/Iβ) to the easily degradable para-crystalline and amorphous celluloses were the characteristics accounted for efficient enzymatic deconstruction of B. davidii after EOP.
The third study provides a detailed elucidation of the chemical structure of ethanol organosolv lignin (EOL) of B. davidii by NMR spectroscopy. Such research was needed to understand the pretreatment mechanism in the context of delignification and alteration of the lignin structure. Future applications of the resulted EOL will be valuable for industrially viable bioethanol production process. EOP mainly cleaved β-O-4' interlinkages via homolysis, decreased the DP of lignin, and increased the degree of condensation of lignin. EOL had low oxygen content, molecular weight, and aliphatic OH as well as high phenolic OH, which are qualities that make it suitable for different co-product applications.
The last study provides information on the anatomical characteristics of pretreated B. davidii biomass after EOP. The importance of this research was to further understand the alterations that occur to the cellular structure of the biomass which can then be correlated with its enzymatic digestibility. The results concluded that the physical distribution of lignin within the biomass matrix and the partial removal of middle lamella lignin were key factors influencing enzymatic hydrolysis.
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Fundamentos jurídicos das matas ciliares e sua importância na tutela jurídica dos cursos d´águaRosa, Mardióli Dalla 03 December 2010 (has links)
O presente trabalho tem por objeto a análise do ordenamento jurídico no que tange à utilização racional dos recursos hídricos. Tendo em vista a escassez de água em diversos países, a problemática da poluição e a má utilização do recurso hídrico, é claro que não só a sociedade se conscientize a utilizar tecnologias sustentáveis, como a ciência jurídica colabore com a normatização de incentivos fiscais e punitivos para preservação desse bem imprescindível à vida. Em virtude do consumo desenfreado, tem-se falado muito em sustentabilidade e a educação ambiental tem sido eleita como uma das ferramentas chaves a ser utilizada para mudar esse cenário caótico. Pretende-se analisar de que forma as matas ciliares atuam na proteção, tutela dos corpos de água. Observa-se que para a construção do meio ambiente ecologicamente equilibrado há necessidade da modificação dos paradigmas jurídicos referentes aos bens ambientais, entre eles o de uso comum do povo. Salienta-se que é indispensável para a vida humana, que o meio ambiente ecologicamente equilibrado seja assegurado por meio de um sistema legal que imponha padrões de qualidade e restrinja o uso de bens ambientais pelo homem, neste caso, as áreas de preservação permanente. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-06-02T19:31:44Z
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Dissertacao Mardioli Dalla Rosa.pdf: 1139276 bytes, checksum: a5cbbc4ff83b379b643daf1cc5791a15 (MD5) / Made available in DSpace on 2014-06-02T19:31:44Z (GMT). No. of bitstreams: 1
Dissertacao Mardioli Dalla Rosa.pdf: 1139276 bytes, checksum: a5cbbc4ff83b379b643daf1cc5791a15 (MD5) / The present work aims at the analysis of the legal system regarding the rational use of water resources. Given the scarcity of water in several countries, the problems of pollution and misuse of water resources is clear that not only the company is aware to use sustainable technologies, such as science work with the legal norms and punitive tax incentives for preservation of good essential to life. Due to the unbridled consumption, has been much talk on sustainability and environmental education has been voted one of the key tools being used to change this chaotic scenario. The aim is to examine how the function is to protect riparian forests, protection of water bodies. It is observed that for the construction of an ecologically balanced environment is necessary to modify the legal paradigms relating to environmental goods, including the use of the common people. Underlines that it is indispensable to humsn life, the ecologically balanced environment is ensured throught a legal system that enforces quality standads and restrict the use of use of environmental goods by man, in this case, the areas of permanent preservation.
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Fundamentos jurídicos das matas ciliares e sua importância na tutela jurídica dos cursos d´águaRosa, Mardióli Dalla 03 December 2010 (has links)
O presente trabalho tem por objeto a análise do ordenamento jurídico no que tange à utilização racional dos recursos hídricos. Tendo em vista a escassez de água em diversos países, a problemática da poluição e a má utilização do recurso hídrico, é claro que não só a sociedade se conscientize a utilizar tecnologias sustentáveis, como a ciência jurídica colabore com a normatização de incentivos fiscais e punitivos para preservação desse bem imprescindível à vida. Em virtude do consumo desenfreado, tem-se falado muito em sustentabilidade e a educação ambiental tem sido eleita como uma das ferramentas chaves a ser utilizada para mudar esse cenário caótico. Pretende-se analisar de que forma as matas ciliares atuam na proteção, tutela dos corpos de água. Observa-se que para a construção do meio ambiente ecologicamente equilibrado há necessidade da modificação dos paradigmas jurídicos referentes aos bens ambientais, entre eles o de uso comum do povo. Salienta-se que é indispensável para a vida humana, que o meio ambiente ecologicamente equilibrado seja assegurado por meio de um sistema legal que imponha padrões de qualidade e restrinja o uso de bens ambientais pelo homem, neste caso, as áreas de preservação permanente. / The present work aims at the analysis of the legal system regarding the rational use of water resources. Given the scarcity of water in several countries, the problems of pollution and misuse of water resources is clear that not only the company is aware to use sustainable technologies, such as science work with the legal norms and punitive tax incentives for preservation of good essential to life. Due to the unbridled consumption, has been much talk on sustainability and environmental education has been voted one of the key tools being used to change this chaotic scenario. The aim is to examine how the function is to protect riparian forests, protection of water bodies. It is observed that for the construction of an ecologically balanced environment is necessary to modify the legal paradigms relating to environmental goods, including the use of the common people. Underlines that it is indispensable to humsn life, the ecologically balanced environment is ensured throught a legal system that enforces quality standads and restrict the use of use of environmental goods by man, in this case, the areas of permanent preservation.
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Development and Characterization of Multi-scale Polymer Composite Materials for Tribological ApplicationsJain, Ayush January 2017 (has links)
With industries aiming at higher efficiencies, lightweight parts, and easier manufacturability there has been a recent trend of replacing the metallic materials with polymeric materials and its composites. Particularly in the automotive industry, there is a demand of replacing metallic material of bushes and bearings with polymer based materials (PBM). For these heavy performance requirements (as in automobiles), the commonly used industrial polymers like Acetal and Nylon fail to provide good mechanical and tribological performance. High-performance polymer like Polyphenylene Sulfide (PPS) is a relatively newer material and shows a potential of being a PBM alternative for metallic bearings in automobiles if their tribological performance can be improved. One of the ways of improving the tribological performance of the polymer is by the addition of filler material, hence making a polymer composite. In this study, we used Short Carbon Fibre as micro-reinforcement material and Nano-diamonds and Graphene Oxide as nano-reinforcement material to make PPS composites. The varying mechanical and tribological behaviour of PPS composites with different weight percentage of reinforcement materials was investigated. The optimum composition of the reinforcement materials was identified, which resulted in significant improvement in mechanical and tribological properties of the base material.
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