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Patch test analysis using horizontal cross section of an underwater feature for multibeam echo sounding systemKao, I-chieh 09 February 2009 (has links)
Multibeam system is a rather new technique for generating huge digital terrain model quickly. If the primitive data does not perform quality control and the calibration process, inconsistency among the axes of transducer, motion sensor and gyrocompass may results in unreasonable underwater topography.
The problem in the hydrographic surveying in the practice is not easy to seek for the suitable seabed or underwater feature for patch test at present. This research attempts to use fewer horizontal cross section of an underwater feature to compute roll, pitch and yaw deviation angle that differs from traditional vertical profile computing approach for patch test. And using different survey line combination and different underwater topography condition to achieve independent solution of angle deviation . We also design the new processing order for patch test. It hopes to utilize this concept to carry out patch test by the common underwater feature or recycling man-made object for resolving this problem in the future.
The experimental results show that new calibration can get the same achievement as the traditional calibration by the CARIS HIPS software, and the calibration results applied in the cross check lines can pass through IHO special standard. It shows that the calibration results not only suit for calibration survey lines, but also good for rest of the area. It proves the proposed new patch test is feasible.
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Hydrologic Validation of Real-Time Weather Radar VPR Correction MethodsKlyszejko, Erika Suzanne January 2006 (has links)
Weather radar has long been recognized as a potentially powerful tool for hydrological modelling. A single radar station is able to provide detailed precipitation information over entire watersheds. The operational use of radar in water resources applications, however, has been limited. Interpretation of raw radar data requires several rigorous analytical steps and a solid understanding of the technology. In general, hydrologists’ lack of meteorological background and the persistence of systematic errors within the data, has led to a common mistrust of radar-estimated precipitation values.
As part of the Enhanced Nowcasting of Extreme Weather project, researchers at McGill University’s J.S. Marshall Radar Observatory in Montreal have been working to improve real-time quantitative precipitation estimates (QPEs). The aim is to create real-time radar precipitation products for the water resource community that are reliable and properly validated.
The validation of QPEs is traditionally based on how well observed measurements agree with data from a precipitation gauge network. Comparisons between radar and precipitation gauge quantities, however, can be misleading. Data from a precipitation gauge network represents a series of single-point observations taken near ground surface. Radar, however, estimates the average rate of precipitation over a given area (i.e. a 1-km grid cell) based on the intensity of reflected microwaves at altitudes exceeding 1 km. Additionally, both measurement techniques are susceptible to a number of sources of error that further confound efforts to compare the two.
One of the greatest challenges facing radar meteorologists is the variation in the vertical profile of reflectivity (VPR). A radar unit creates a volumetric scan of the atmosphere by emitting microwave beams at several elevation angles. As a beam travels away from the radar, its distance from ground surface increases. Different precipitation types are sampled at a number of heights (i.e. snow above the 0º C elevation and rain below it) that vary with range. The difficulty lies in estimating the intensity of precipitation at the Earth’s surface, based on measurements taken aloft. Scientists at McGill University have incorporated VPR correction techniques into algorithms used to automatically convert raw radar data into quantitative hydrological products.
This thesis evaluates three real-time radar precipitation products from McGill University’s J.S. Marshall Radar Observatory in the context of hydrological modelling. The C0 radar product consists of radar precipitation estimates that are filtered for erroneous data, such as ground clutter and anomalous precipitation. The C2 and C3 radar products use different VPR correction techniques to improve upon the C0 product. The WATFLOOD hydrological model is used to assess the ability of each radar product to estimate precipitation over several watersheds within the McGill radar domain. It is proposed that using a watershed as sample area can reduce the error associated with sampling differences between radar and precipitation gauges and allow for the evaluation of a precipitation product over space and time.
The WATFLOOD model is run continuously over a four-year period, using each radar product as precipitation input. Streamflow hydrographs are generated for 39 gauging stations within the radar domain, which includes parts of eastern Ontario, south-western Quebec and northern New York and Vermont, and compared to observed measurements. Streamflows are also modelled using distributed precipitation gauge data from 44 meteorological stations concentrated around the Montreal region.
Analysis of select streamflow events reveals that despite the non-ideal placement of precipitation gauges throughout the study area, distributed precipitation gauge data are able to reproduce hydrological events with greater accuracy and consistency than any of the provided radar products. Precipitation estimates within the McGill radar domain are found to only be useful in areas within the Doppler range (120-km) where the radar beam is unobstructed by physiographic or man-made features.
Among radar products, the C2 VPR-corrected product performed best during the greatest number of the flood events throughout the study area.
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Hydrologic Validation of Real-Time Weather Radar VPR Correction MethodsKlyszejko, Erika Suzanne January 2006 (has links)
Weather radar has long been recognized as a potentially powerful tool for hydrological modelling. A single radar station is able to provide detailed precipitation information over entire watersheds. The operational use of radar in water resources applications, however, has been limited. Interpretation of raw radar data requires several rigorous analytical steps and a solid understanding of the technology. In general, hydrologists’ lack of meteorological background and the persistence of systematic errors within the data, has led to a common mistrust of radar-estimated precipitation values.
As part of the Enhanced Nowcasting of Extreme Weather project, researchers at McGill University’s J.S. Marshall Radar Observatory in Montreal have been working to improve real-time quantitative precipitation estimates (QPEs). The aim is to create real-time radar precipitation products for the water resource community that are reliable and properly validated.
The validation of QPEs is traditionally based on how well observed measurements agree with data from a precipitation gauge network. Comparisons between radar and precipitation gauge quantities, however, can be misleading. Data from a precipitation gauge network represents a series of single-point observations taken near ground surface. Radar, however, estimates the average rate of precipitation over a given area (i.e. a 1-km grid cell) based on the intensity of reflected microwaves at altitudes exceeding 1 km. Additionally, both measurement techniques are susceptible to a number of sources of error that further confound efforts to compare the two.
One of the greatest challenges facing radar meteorologists is the variation in the vertical profile of reflectivity (VPR). A radar unit creates a volumetric scan of the atmosphere by emitting microwave beams at several elevation angles. As a beam travels away from the radar, its distance from ground surface increases. Different precipitation types are sampled at a number of heights (i.e. snow above the 0º C elevation and rain below it) that vary with range. The difficulty lies in estimating the intensity of precipitation at the Earth’s surface, based on measurements taken aloft. Scientists at McGill University have incorporated VPR correction techniques into algorithms used to automatically convert raw radar data into quantitative hydrological products.
This thesis evaluates three real-time radar precipitation products from McGill University’s J.S. Marshall Radar Observatory in the context of hydrological modelling. The C0 radar product consists of radar precipitation estimates that are filtered for erroneous data, such as ground clutter and anomalous precipitation. The C2 and C3 radar products use different VPR correction techniques to improve upon the C0 product. The WATFLOOD hydrological model is used to assess the ability of each radar product to estimate precipitation over several watersheds within the McGill radar domain. It is proposed that using a watershed as sample area can reduce the error associated with sampling differences between radar and precipitation gauges and allow for the evaluation of a precipitation product over space and time.
The WATFLOOD model is run continuously over a four-year period, using each radar product as precipitation input. Streamflow hydrographs are generated for 39 gauging stations within the radar domain, which includes parts of eastern Ontario, south-western Quebec and northern New York and Vermont, and compared to observed measurements. Streamflows are also modelled using distributed precipitation gauge data from 44 meteorological stations concentrated around the Montreal region.
Analysis of select streamflow events reveals that despite the non-ideal placement of precipitation gauges throughout the study area, distributed precipitation gauge data are able to reproduce hydrological events with greater accuracy and consistency than any of the provided radar products. Precipitation estimates within the McGill radar domain are found to only be useful in areas within the Doppler range (120-km) where the radar beam is unobstructed by physiographic or man-made features.
Among radar products, the C2 VPR-corrected product performed best during the greatest number of the flood events throughout the study area.
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LiDAR technology applied to vegetation quantification and qualification / O uso de tecnologia LiDAR para quantificação e qualificação da vegetaçãoGörgens, Eric Bastos 12 December 2014 (has links)
The methodology to quantify vegetation from airborne laser scanning (or LiDAR - Light Detection And Ranging) is somehow consolidated, but some concerns are still in the checklist of the scientific community. This thesis aims to bring some of those concerns and try to contribute with some results and insights. Four aspects were studied along this thesis. In the first study, the effect of threshold heights (minimum height and height break) in the quality of the set of metrics was investigated aiming the volume estimation of a eucalyptus plantation. The results indicate that higher threshold height may return a better set of metrics. The impact of threshold height was more evident in young stands and for canopy density metrics. In the second study, the stability of the LiDAR metrics between different LiDAR surveys over the same area was analyzed. This study demonstrated how the selection of stable metrics contributed to generate reliable models between different data sets. According to our results, the height metrics provided the greatest stability when used in the models, specifically the higher percentiles (>50%) and the mode. The third study was designed to evaluate the use of machine learning tools to estimate wood volume of eucalyptus plantations from LiDAR metrics. Rather than being limited to a subset of LiDAR metrics in attempting explain as much variability in a dependent variable as possible, artificial intelligence tools explored the complete metrics set when looking for patterns between LiDAR metrics and stand volume. The fourth and last study has focused upon several highly important forest typologies, and shown that it is possible to differentiate the typologies through their vertical profiles as derived from airborne laser surveys. The size of the sampling cell does have an influence on the behavior observed in analyses of spatial dependence. Each typology has its own specific characteristics, which will need to be taken into consideration in projects targeting monitoring, inventory construction, and mapping based upon airborne laser surveys. The determination of a converged vertical profile could be achieved with data representing 10 % of the area for all typologies, while for some typologies 2 % coverage was sufficient. / A metodologia para quantificar vegetação a partir de dados LiDAR (Light Detection And Ranging) está de certa forma consolidada, porém ainda existem pontos a serem esclarecidos que permanecem na lista da comunidade científica. Quatro aspectos foram estudos nesta tese. No primeiro estudo, foi investigado a influência das alturas de referência (altura mínima e altura de quebra) na qualidade do conjunto de métricas extraído visando estimação do volume de um plantio de eucalipto. Os resultados indicaram que valor mais altos de alturas de referência retornaram um conjunto de métricas melhor. O efeito das alturas de referência foi mais evidente em povoamentos jovens e para as métricas de densidade. No segundo estudo, avaliou-se a estabilidade de métricas LiDAR derivadas para uma mesma área sobrevoada com diferentes configurações de equipamentos e voo. Este estudo apresentou como a seleção de métricas estáveis pode contribuir para a geração de modelos compatíveis com diferentes bases de dados LiDAR. De acordo com os resultados, as métricas de altura foram mais estáveis que as métricas de densidade, com destaque para os percentis acima de 50% e a moda. O terceiro estudo avaliou o uso de máquinas de aprendizado para a estimação do volume em nível de povoamento de plantios de eucalipto a partir de métricas LiDAR. Ao invés de estarem limitados a um pequeno subconjunto de métricas na tentativa de explicar a maior parte possível da variabilidade total dos dados, as técnicas de inteligência artificial permitiram explorar todo o conjunto de dados e detectar padrões que estimaram o volume em nível de povoamento a partir do conjunto de métricas. O quarto e último estudo focou em sete áreas de diferentes tipologias florestais brasileiras, estudando os seus perfis verticais de dossel. O estudo mostrou que é possível diferenciar estas tipologias com base no perfil vertical derivado de levantamentos LiDAR. Foi observado também que o tamanho das parcelas possui diferentes níveis de dependência espacial. Cada tipologia possui características específicas que precisam ser levadas em considerações em projetos de monitoramento, inventário e mapeamento baseado em levantamentos LiDAR. O estudo mostrou que é possível determinar o perfil vertical de dossel a partir da cobertura de 10% da área, chegando a algumas tipologias em apenas 2% da área.
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Vertical Profile and Correlation Analysis of Ozone and Its Precursors in Coastal Region of KaohsiungLiu, Yu-Fu 24 August 2010 (has links)
Metro Kaohsiung with high percentage (6-10 %) of poor air quality (PSI>100) has been announced officially by Taiwan Environmental Protection Administration (TEPA) as the worst air quality region among seven Air Quality Zones (AQZ) in Taiwan. Ozone is one of two major air pollutants that are responsible for the poor air quality. In this study, the vertical concentration profiles of ozone and its precursors (NOX and VOCs) at eight sites were measured by tethered balloons with air pumps and tedlar sampling bags. This method was used to investigate the vertical profile and the tempospatial distribution of ozone and its precursors in offshore/inland regions. This study further investigated ozone formation mechanism and air mass trajectory via simultaneous air quality sampling around the coastal region of metro Kaohsiung.
This study sampled the vertical concentration profiles of ozone and its precursors at both inland and offshore sites during eight intensive sampling periods on August 16-17 and November 2-3, 2006, January 24-25, March 6-7 and May 2-3, 2007, October 30-31, 2008, and March 11-12 and July 15-16, 2009. Eight sampling periods were divided into the sea-land breeze period, the northeast monsoon period, and the mixing wind field period. During the sea-land breeze period, the wind direction changed 90˚ and more between daytime and nighttime, and the wind speeds of the sea breezes varied significantly than those of the land breezes. During the northeast monsoon period, prevailing wind blew from the north (300~60˚) with the average wind speeds of 1~4 m/s. During the mixing wind field period, the wind direction varied significantly from 270˚ to 90˚ with the average wind speeds of 1~3 m/s.
Results obtained from the vertical profiles showed that O3 concentration appeared stratification phenomenon at 40 out of 64 sampling sites, in which its precursors (NOX or VOCs) demonstrated stratification phenomenon at 30 sampling sites, accounting for 75 % of total O3 stratification. It suggested that ozone and its precursors had strong correlation with each other. The linear slope of the titration effect showed that the intensity of titration effect at night during the northeast monsoon period was larger and had higher correlation (R> 0.7), and followed by the mixing wind field period and the sea-land breeze period. This phenomenon correlated closely with meteorological conditions, the concentrations of O3 precursors, and solar radiation intensity. Therefore, O3 concentration at night during the northeast monsoon period was lower than those of the sea-land breeze period.
Results obtained from VOCs measurement indicated that the major species of VOCs was acetone which accounted for 16.25~64.05 % of total TVOCs-C2 in the offshore region. High concentration of TVOCs-C2 was affected by the usage of organic solvents. While, the major species of VOCs in the inland region was toluene which accounted for 6.41~43.77 % of total TVOCs-C2. Furthermore, results obtained from backward trajectory showed that air pollutants emited from land sources could transport to the offshore region, resulting in high concentration of oversea NOX and VOCs. Major species of VOCs for high O3 formation potential were aromatics and vinyls at the height of 0~500 m around the coastal region of metro Kaohsiung.
The control of O3 precursors concentration showed that the ratio of [TVOCs-C2]/[NOX] in the offshore region was higher, indicating that O3 formation was NOX-limited. Therefore, NOX must be controlled for reducing O3 formation. However, the ratio of [TVOCs-C2]/[NOX] in the inland region was lower, some cases even below 4, showing that O3 formation was VOCs-limited. Thus, VOCs must be controlled for reducing O3 formation.
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Vertical Distribution and Seasonal Variation of Volatile Organic Compounds in the Ambient Atmosphere of a Petrochemical Industrial ComplexYang, Jhih-Jhe 02 September 2011 (has links)
The emission of volatile organic compounds (VOCs) and odors from petrochemical industrial complex, including China Petroleum company (CPC),Renwu and Dazher petrochemical industrial parks, causes poor air quality of northern Kaohsiung. The removal efficiencies of elevated stacks and flares might play
important roles on ambient air quality in metro Kaohsiung. Consequently, this study
applied a tethered balloon technology to measure the vertical profile of VOCs, and
ascertained their three dimensional dispersion in the atmosphere.
The vertical profile of VOCs in ambient atmosphere surrounding the
petrochemical industrial complex was measured during the intensive sampling periods
(September 17-18th and December 20-21st, 2009 and April 8-9th and July 7-8th, 2010).
Moreover, this study was designed to sample and analyze VOCs emitted from
elevated stacks and flares, and estimate their emission factors. Finally, the source
identification and ozone formation were further determined by principal component
analysis (PCA) and ozone formation potential (OFP).
This study found that some regions had relatively poorer air quality than other
regions surrounding the petrochemical industrial complex. Most sampling sites with
poor air quality were located at the downwind region of the petrochemical industrial
complex, particularly with the prevailing winds blown from the northwest. Moreover,
stratification phenomena were frequently observed at most sampling sites, indicating
that high-altitude VOCs pollution should be considered for ambient air quality.
This study revealed that the indicators of VOCs in northern Kaohsiung were
toluene, C2 (ethylene+acetylene+ethane), and acetone. Vertical sampling of VOCs
showed that the species of VOCs at the ground and high altitude were different,
suggesting that ambient air quality at high altitude might be affected by the emission
of VOCs from elevated stacks and flares at the petrochemical industrial complex.
Results obtained from PCA showed that the major sources of VOCs in the
ambient atmosphere of the petrochemical industrial complex were similar to the characteristics of VOCs emitted from the petrochemical industrial complex. The
characteristics of VOCs at high altitude had strong correlation with petrochemical
industry, indicating that the ambient air quality of northern Kaohsiung was highly
influenced by the emission of VOCs from high stacks and flares. In addition, major
VOCs for O3 formation potential at northern Kaohsiung were aromatics and vinyls,
with particular species of toluene and C2. Moreover, air pollution episodes resulting
from high O3 concentration was usually observed in early winter.
Flare sampling results indicated that major VOCs emitted from the ground flare
of CPC were alkanes and vinyls. The average removal efficiency of TVOCs was
98.2%. The average emission factor of VOCs was 0.0186 kg NMHC/kg flare gas. In
addition, stack sampling results indicated that the emission factors of crude oil
distillation process (P105), mixing process (P060), and rubber manufacturing process
(P408) were 0.105, 1.11, and 61.97 g/Kl, respectively. The emission factor of P105
was lower than AP-42, while that of P408 was higher than AP-42.
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LiDAR technology applied to vegetation quantification and qualification / O uso de tecnologia LiDAR para quantificação e qualificação da vegetaçãoEric Bastos Görgens 12 December 2014 (has links)
The methodology to quantify vegetation from airborne laser scanning (or LiDAR - Light Detection And Ranging) is somehow consolidated, but some concerns are still in the checklist of the scientific community. This thesis aims to bring some of those concerns and try to contribute with some results and insights. Four aspects were studied along this thesis. In the first study, the effect of threshold heights (minimum height and height break) in the quality of the set of metrics was investigated aiming the volume estimation of a eucalyptus plantation. The results indicate that higher threshold height may return a better set of metrics. The impact of threshold height was more evident in young stands and for canopy density metrics. In the second study, the stability of the LiDAR metrics between different LiDAR surveys over the same area was analyzed. This study demonstrated how the selection of stable metrics contributed to generate reliable models between different data sets. According to our results, the height metrics provided the greatest stability when used in the models, specifically the higher percentiles (>50%) and the mode. The third study was designed to evaluate the use of machine learning tools to estimate wood volume of eucalyptus plantations from LiDAR metrics. Rather than being limited to a subset of LiDAR metrics in attempting explain as much variability in a dependent variable as possible, artificial intelligence tools explored the complete metrics set when looking for patterns between LiDAR metrics and stand volume. The fourth and last study has focused upon several highly important forest typologies, and shown that it is possible to differentiate the typologies through their vertical profiles as derived from airborne laser surveys. The size of the sampling cell does have an influence on the behavior observed in analyses of spatial dependence. Each typology has its own specific characteristics, which will need to be taken into consideration in projects targeting monitoring, inventory construction, and mapping based upon airborne laser surveys. The determination of a converged vertical profile could be achieved with data representing 10 % of the area for all typologies, while for some typologies 2 % coverage was sufficient. / A metodologia para quantificar vegetação a partir de dados LiDAR (Light Detection And Ranging) está de certa forma consolidada, porém ainda existem pontos a serem esclarecidos que permanecem na lista da comunidade científica. Quatro aspectos foram estudos nesta tese. No primeiro estudo, foi investigado a influência das alturas de referência (altura mínima e altura de quebra) na qualidade do conjunto de métricas extraído visando estimação do volume de um plantio de eucalipto. Os resultados indicaram que valor mais altos de alturas de referência retornaram um conjunto de métricas melhor. O efeito das alturas de referência foi mais evidente em povoamentos jovens e para as métricas de densidade. No segundo estudo, avaliou-se a estabilidade de métricas LiDAR derivadas para uma mesma área sobrevoada com diferentes configurações de equipamentos e voo. Este estudo apresentou como a seleção de métricas estáveis pode contribuir para a geração de modelos compatíveis com diferentes bases de dados LiDAR. De acordo com os resultados, as métricas de altura foram mais estáveis que as métricas de densidade, com destaque para os percentis acima de 50% e a moda. O terceiro estudo avaliou o uso de máquinas de aprendizado para a estimação do volume em nível de povoamento de plantios de eucalipto a partir de métricas LiDAR. Ao invés de estarem limitados a um pequeno subconjunto de métricas na tentativa de explicar a maior parte possível da variabilidade total dos dados, as técnicas de inteligência artificial permitiram explorar todo o conjunto de dados e detectar padrões que estimaram o volume em nível de povoamento a partir do conjunto de métricas. O quarto e último estudo focou em sete áreas de diferentes tipologias florestais brasileiras, estudando os seus perfis verticais de dossel. O estudo mostrou que é possível diferenciar estas tipologias com base no perfil vertical derivado de levantamentos LiDAR. Foi observado também que o tamanho das parcelas possui diferentes níveis de dependência espacial. Cada tipologia possui características específicas que precisam ser levadas em considerações em projetos de monitoramento, inventário e mapeamento baseado em levantamentos LiDAR. O estudo mostrou que é possível determinar o perfil vertical de dossel a partir da cobertura de 10% da área, chegando a algumas tipologias em apenas 2% da área.
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Biomass burning : particle emissions, characteristics, and airborne measurementsWardoyo, Arinto Yudi January 2007 (has links)
Biomass burning started to attract attention since the last decade because of its impacts on the atmosphere and the environmental air quality, as well as significant potential effects on human health and global climate change. Knowledge of particle emission characteristics from biomass burning is crucially important for the quantitative assessment of the potential impacts. This thesis presents the results of study aimed towards comprehensive characterization of particle emissions from biomass burning. The study was conducted both under controlled laboratory conditions, to quantify the particle size distribution and emission factors by taking into account various factors which may affect the particle characteristics, and in the field, to investigate biomass burning processes in the real life situations and to examine vertical profile of particles in the atmosphere. To simulate different environmental conditions, a new technique has been developed for investigating particle emissions from biomass burning in the laboratory. As biomass burning may occur in a field at various wind speeds and burning rates, the technique was designed to allow adjustment of the flow rates of the air introduced into the chamber, in order to control burning under different conditions. In addition, the technique design has enabled alteration of the high particle concentrations, allowing conducting measurements with the instrumentations that had the upper concentration limits exciding the concentrations characteristic to the biomass burning. The technique was applied to characterize particle emissions from burning of several tree species common to Australian forests. The aerosol particles were characterized in terms of size distribution and emission factors, such as PM2.5 particle mass emission factor and particle number emission factor, under various burning conditions. The characteristics of particles over a range of burning phases (e.g., ignition, flaming, and smoldering) were also investigated. The results showed that particle characteristics depend on the type of tree, part of tree, and the burning rate. In particular, fast burning of the wood samples produced particles with the CMD of 60 nm during the ignition phase and 30 nm for the rest of the burning process. Slow burning of the wood samples produced large particles with the CMD of 120 nm, 60 nm and 40 nm for the ignition, flaming and smoldering phases, respectively. The CMD of particles emitted by burning the leaves and branches was found to be 50 nm for the flaming phase and 30 nm for the smoldering phase, under fast burning conditions. Under slow burning conditions, the CMD of particles was found to be between 100 to 200 nm for the ignition and flaming phase, and 50 nm for the smoldering phase. For fast burning, the average particle number emission factors were between 3.3 to 5.7 x 1015 particles/kg for wood and 0.5 to 6.9 x 1015 particles/kg for leaves and branches. The PM2.5 emission factors were between 140 to 210 mg/kg for wood and 450 to 4700 mg/kg for leaves and branches. For slow burning conditions, the average particle number emission factors were between 2.8 to 44.8 x 1013 particles/kg for wood and 0.5 to 9.3 x 1013 particles/kg for leaves and branches, and the PM2.5 emissions factors were between 120 to 480 mg/kg for wood and 3300 to 4900 mg/kg for leaves and branches. The field measurements were conducted to investigate particle emissions from biomass burning in the Northern Territory of Australia over dry seasons. The results of field studies revealed that diameters of particles in ambient air emissions were within the size range observed during laboratory investigations. The laboratory measurements found that the particles released during the controlled burning were of a diameter between 30 and 210 nm, depending on the burning conditions. Under fast burning conditions, smaller particles were produced with a diameter in the range of 30 to 60 nm, whilst larger particles, with a diameter between 60 nm and 210 nm, were produced during slow burning. The airborne field measurements of biomass particles found that most of the particles measured under the boundary layer had a CMD of (83 ± 13) nm during the early dry season (EDS), and (127 ± 6) nm during the late dry season (LDS). The characteristics of ambient particles were found to be significantly different at the EDS and the LDS due to several factors including moisture content of vegetation, location of fires related to the flight paths, intensity of fires, and burned areas. Specifically, the investigations of the vertical profiles of particles in the atmosphere have revealed significant differences in the particle properties during early dry season and late dry season. The characteristics of particle size distribution played a significant role in these differences.
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Estrutura e composição de espécies arbóreas em um trecho de floresta ombrófila densa atlântica no litoral norte do estado de São Paulo e padrões de similaridade florística em escala regional /Prata, Eduardo Magalhães Borges. January 2009 (has links)
Orientador: Marco Antonio de Assis / Banca: Sergius Gandolfi / Banca: Natália Macedo Ivanauskas / Resumo: Este trabalho foi desenvolvido em um trecho de Floresta Ombrófila Densa Atlântica no Núcleo Picinguaba do Parque Estadual da Serra do Mar, litoral norte do Estado de São Paulo, município de Ubatuba-SP. A área de estudo corresponde a uma das parcelas amostrais (Parcela D) do Projeto Temático "Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar" do Programa BIOTA-FAPESP. Nosso estudo foi estruturado em três capítulos. No Capítulo 1, objetivamos descrever a composição florística e a estrutura da comunidade arbórea em uma parcela de 1 ha; avaliar o padrão de distribuição espacial das espécies e; investigar a ocorrência de correlações entre a distribuição das espécies e as variáveis 'altitude média', 'desnível topográfico', 'cobertura rochosa', 'presença de água na superfície do solo', 'distância do rio' e 'luz no interior da parcela', através de uma CCA. No Capítulo 2, investigamos a distribuição da riqueza e da diversidade de espécies ao longo do perfil vertical, considerando os estratos adultos e regenerantes da comunidade, buscando responder em quais níveis de altura está presente o maior número de espécies arbóreas. No Capítulo 3, avaliamos a distribuição das espécies e os padrões de similaridade florística entre áreas de Floresta Ombrófila Densa das Terras Baixas e Submontana situadas ao longo de um gradiente latitudinal entre os Estados do Rio de Janeiro e Santa Catarina. Nossos resultados revelaram valores elevados de riqueza (161 spp) e diversidade (H' = 4,0) no hectare analisado. Observamos padrões de distribuição espacial aleatórios para a maioria das espécies na comunidade, onde apenas Euterpe edulis, Alsophila sternbergii e Coussarea meridionalis var. porophylla apresentaram padrão agregado... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study was conducted in a stretch of Atlantic Rain Forest at Núcleo Picinguaba do Parque Estadual da Serra do Mar, northern coast of São Paulo State, municipality of Ubatuba-SP. The study area represents one of the sample plots (Plot D) of the Project "Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virginia do Parque Estadual da Serra do Mar" Programa BIOTA-FAPESP. Our study was structured in three chapters. In Chapter 1, we aimed to describe the floristic composition and tree structure in a plot of 1 ha; assess the pattern of spatial distribution of species and, to investigate the occurrence of correlations between species distribution and the variables 'average height', 'topographic gap', 'cover rock ', 'presence of water on soil surface', 'distance from the river' and 'light in the interior of the plot', through a CCA. In Chapter 2, we investigated species richness and diversity distribution along the vertical profile, involving both regenerating and adult strata, in order to answer which height levels show the greatest number of tree species. In Chapter 3, we assessed species distribution and the occurrence of patterns on floristic similarities between areas of Lowlands and Submontanes Atlantic Rain Forests areas along a latitudinal gradient between Rio de Janeiro and Santa Catarina states. Our results revealed high richness (161 spp) and diversity (H' = 4.0) values in the area examined. We observed random patterns on spatial distribution for most species in the community, where only Euterpe edulis, Alsophila sternbergii and Coussarea meridionalis var. porophylla showed clumped patterns. Significant correlations between species and environmental variables matrices were detected for axis 1 of CCA (p = 0.001). The regenerating stratum showed greater floristic richness than adult stratum and higher values... (Complete abstract click electronic access below) / Mestre
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Estrutura e composição de espécies arbóreas em um trecho de floresta ombrófila densa atlântica no litoral norte do estado de São Paulo e padrões de similaridade florística em escala regionalPrata, Eduardo Magalhães Borges [UNESP] 27 March 2009 (has links) (PDF)
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prata_emb_me_rcla.pdf: 2137879 bytes, checksum: f0087a39dbca5bca9a452e4b2037187e (MD5) / Este trabalho foi desenvolvido em um trecho de Floresta Ombrófila Densa Atlântica no Núcleo Picinguaba do Parque Estadual da Serra do Mar, litoral norte do Estado de São Paulo, município de Ubatuba-SP. A área de estudo corresponde a uma das parcelas amostrais (Parcela D) do Projeto Temático “Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar” do Programa BIOTA-FAPESP. Nosso estudo foi estruturado em três capítulos. No Capítulo 1, objetivamos descrever a composição florística e a estrutura da comunidade arbórea em uma parcela de 1 ha; avaliar o padrão de distribuição espacial das espécies e; investigar a ocorrência de correlações entre a distribuição das espécies e as variáveis ‘altitude média’, ‘desnível topográfico’, ‘cobertura rochosa’, ‘presença de água na superfície do solo’, ‘distância do rio’ e ‘luz no interior da parcela’, através de uma CCA. No Capítulo 2, investigamos a distribuição da riqueza e da diversidade de espécies ao longo do perfil vertical, considerando os estratos adultos e regenerantes da comunidade, buscando responder em quais níveis de altura está presente o maior número de espécies arbóreas. No Capítulo 3, avaliamos a distribuição das espécies e os padrões de similaridade florística entre áreas de Floresta Ombrófila Densa das Terras Baixas e Submontana situadas ao longo de um gradiente latitudinal entre os Estados do Rio de Janeiro e Santa Catarina. Nossos resultados revelaram valores elevados de riqueza (161 spp) e diversidade (H' = 4,0) no hectare analisado. Observamos padrões de distribuição espacial aleatórios para a maioria das espécies na comunidade, onde apenas Euterpe edulis, Alsophila sternbergii e Coussarea meridionalis var. porophylla apresentaram padrão agregado... / This study was conducted in a stretch of Atlantic Rain Forest at Núcleo Picinguaba do Parque Estadual da Serra do Mar, northern coast of São Paulo State, municipality of Ubatuba-SP. The study area represents one of the sample plots (Plot D) of the Project Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virginia do Parque Estadual da Serra do Mar Programa BIOTA-FAPESP. Our study was structured in three chapters. In Chapter 1, we aimed to describe the floristic composition and tree structure in a plot of 1 ha; assess the pattern of spatial distribution of species and, to investigate the occurrence of correlations between species distribution and the variables 'average height', 'topographic gap', 'cover rock ', 'presence of water on soil surface', 'distance from the river' and 'light in the interior of the plot', through a CCA. In Chapter 2, we investigated species richness and diversity distribution along the vertical profile, involving both regenerating and adult strata, in order to answer which height levels show the greatest number of tree species. In Chapter 3, we assessed species distribution and the occurrence of patterns on floristic similarities between areas of Lowlands and Submontanes Atlantic Rain Forests areas along a latitudinal gradient between Rio de Janeiro and Santa Catarina states. Our results revealed high richness (161 spp) and diversity (H' = 4.0) values in the area examined. We observed random patterns on spatial distribution for most species in the community, where only Euterpe edulis, Alsophila sternbergii and Coussarea meridionalis var. porophylla showed clumped patterns. Significant correlations between species and environmental variables matrices were detected for axis 1 of CCA (p = 0.001). The regenerating stratum showed greater floristic richness than adult stratum and higher values... (Complete abstract click electronic access below)
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