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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Informação polarimétrica PALSAR/ALOS aplicada à discriminação de espécies e estimação de parâmetros morfológicos de macrófitas

Sartori, Lauriana Rúbio [UNESP] 20 April 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-04-20Bitstream added on 2014-06-13T20:21:13Z : No. of bitstreams: 1 sartori_lr_dr_prud.pdf: 4148637 bytes, checksum: 5616600e595cbbe65fef21b03cd5309c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O propósito deste trabalho foi avaliar o potencial dos dados PALSAR polarimétricos para discriminar e mapear espécies de macrófitas (vegetação aquática) de uma área alagável da Amazônia, a planície de inundação do Lago Grande de Monte Alegre, no estado do Pará. A coleta de dados foi realizada quase simultaneamente à aquisição dos dados de radar. Três principais espécies de macrófitas foram encontradas na área: Paspalum repens (PR), Hymenachne amplexicaulis (HA) e Paspalum elephantipes (PE). Variáveis morfológicas foram medidas em campo e usadas para derivar outras variáveis tais como a biomassa. Atributos foram gerados a partir da matriz de covariância [C] extraída da imagem ALOS/PALSAR em modo SLC (single look complex). Os atributos polarimétricos foram analisados para as três espécies e identificados aqueles capazes de discriminar as espécies. Foram aplicadas as seguintes abordagens de classificação: baseada em regras, baseada em modelos de decomposição (Decomposições de Freeman-Durden e Cloude-Pottier), baseada em estatística (Classificação supervisionada baseada na distância Wishart) e híbrida (Classificador Wishart com classes de entrada baseadas na decomposição de Cloude-Pottier). Finalmente, a variável morfológica “volume da haste” foi modelada por regressão múltipla em função de alguns atributos polarimétricos. Os resultados sugerem que a imagem polarimétrica banda L possui potencial para discriminar as espécies de macrófitas, sendo os principais atributos para isso sigma zero HH ( ), sigma zero HV ( ) e sigma zero VV ( ), índice de estrutura da copa... / The purpose of this work was to evaluate the potential of fully polarimetric PALSAR data to discriminate and map macrophyte species in the Amazon floodplain, more specifically in the Monte Alegre Lake, in the state of Pará, Brazil. Fieldwork was carried out almost simultaneously to the radar acquisition. Three main species were found in the study area: Paspalum repens (PR), Hymenachne amplexicaulis (HA) and Paspalum elephantipes (PE). Macrophyte morphological variables were measured on the field and used to derive others variables, like the biomass. Attributes were calculated from the covariance matrix [C] derived from the SLC (single look complex) data. The polarimetric attributes were analyzed for the three species and it was identified that ones capable of discriminating them. The following classification approaches were applied: a rule-based classification, model-based classifications (Freeman-Durden and Cloude-Pottier), a statistical-based classification (supervised classification using Wishart distance measure) and a hybrid classification (Wishart classifier with the input classes based on the H/a plane). Finally, the morphological variable “stem volume” was modeled using multiple regression. The findings suggest that the fully polarimetric image has potential for discriminating plant species, being the main attributes sigma-nought HH ( ), sigma-nought HV ( ) and sigma-nought VV ( ), canopy structure index ( ), HH-VV polarimetric coherence ( ), helicity of the third scattering mechanism (τ ), orientation angle of the first scattering mechanism ( ) and scattering type phase of the first mechanism ( ); among the different classifications, only the supervised (Wishart) and the rule-based discriminated the species, with overall accuracy of 75,04% and 87,18%, respectively; the stem volume was modeled using the following attributes: biomass index ( ), volumetric scattering ... (Complete abstract click electronic access below)
2

Informação polarimétrica PALSAR/ALOS aplicada à discriminação de espécies e estimação de parâmetros morfológicos de macrófitas /

Sartori, Lauriana Rúbio. January 2011 (has links)
Resumo: O propósito deste trabalho foi avaliar o potencial dos dados PALSAR polarimétricos para discriminar e mapear espécies de macrófitas (vegetação aquática) de uma área alagável da Amazônia, a planície de inundação do Lago Grande de Monte Alegre, no estado do Pará. A coleta de dados foi realizada quase simultaneamente à aquisição dos dados de radar. Três principais espécies de macrófitas foram encontradas na área: Paspalum repens (PR), Hymenachne amplexicaulis (HA) e Paspalum elephantipes (PE). Variáveis morfológicas foram medidas em campo e usadas para derivar outras variáveis tais como a biomassa. Atributos foram gerados a partir da matriz de covariância [C] extraída da imagem ALOS/PALSAR em modo SLC (single look complex). Os atributos polarimétricos foram analisados para as três espécies e identificados aqueles capazes de discriminar as espécies. Foram aplicadas as seguintes abordagens de classificação: baseada em regras, baseada em modelos de decomposição (Decomposições de Freeman-Durden e Cloude-Pottier), baseada em estatística (Classificação supervisionada baseada na distância Wishart) e híbrida (Classificador Wishart com classes de entrada baseadas na decomposição de Cloude-Pottier). Finalmente, a variável morfológica "volume da haste" foi modelada por regressão múltipla em função de alguns atributos polarimétricos. Os resultados sugerem que a imagem polarimétrica banda L possui potencial para discriminar as espécies de macrófitas, sendo os principais atributos para isso sigma zero HH ( ), sigma zero HV ( ) e sigma zero VV ( ), índice de estrutura da copa ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of this work was to evaluate the potential of fully polarimetric PALSAR data to discriminate and map macrophyte species in the Amazon floodplain, more specifically in the Monte Alegre Lake, in the state of Pará, Brazil. Fieldwork was carried out almost simultaneously to the radar acquisition. Three main species were found in the study area: Paspalum repens (PR), Hymenachne amplexicaulis (HA) and Paspalum elephantipes (PE). Macrophyte morphological variables were measured on the field and used to derive others variables, like the biomass. Attributes were calculated from the covariance matrix [C] derived from the SLC (single look complex) data. The polarimetric attributes were analyzed for the three species and it was identified that ones capable of discriminating them. The following classification approaches were applied: a rule-based classification, model-based classifications (Freeman-Durden and Cloude-Pottier), a statistical-based classification (supervised classification using Wishart distance measure) and a hybrid classification (Wishart classifier with the input classes based on the H/a plane). Finally, the morphological variable "stem volume" was modeled using multiple regression. The findings suggest that the fully polarimetric image has potential for discriminating plant species, being the main attributes sigma-nought HH ( ), sigma-nought HV ( ) and sigma-nought VV ( ), canopy structure index ( ), HH-VV polarimetric coherence ( ), helicity of the third scattering mechanism (τ ), orientation angle of the first scattering mechanism ( ) and scattering type phase of the first mechanism ( ); among the different classifications, only the supervised (Wishart) and the rule-based discriminated the species, with overall accuracy of 75,04% and 87,18%, respectively; the stem volume was modeled using the following attributes: biomass index ( ), volumetric scattering ... (Complete abstract click electronic access below) / Orientador: Nilton Nobuhiro Imai / Coorientador: José Cláudio Mura / Banca: Evlyn Marcia Leão de Moraes Novo / Banca: Thiago Sanna Freire Silva / Banca: João Roberto dos Santos / Banca: Vilma Mayumi Tachibana / Doutor
3

Optimisation des marais filtrants pour l’abattement du pesticide chlorantraniliprole du ruissellement agricole

Abas, Khalil 02 1900 (has links)
Au cours des dernières décennies, une grande variété de pesticides émergents, tels que le chlorantraniliprole (CAP), ont été introduits malgré le manque de connaissance approfondie de leur risque écotoxicologique. Les marais filtrants (TW) sont des technologies écologiques et durables qui ont montré un grand potentiel d’atténuation des polluants agricoles communs, tels que les pesticides dans le ruissellement. L’objectif de cette étude était d’optimiser l’utilisation du marais filtrant sous-surfacique à écoulement horizontal (HSSF) en déterminant: a) l'effet d’un amendement de biochar au substrat et b) la performance de trois espèces de macrophytes (Phragmites australis subsp. americanus, Scirpus cyperinus et Sporobolus michauxianus) dans l'abattement du CAP du ruissellement agricole. L'efficacité d'abattement a été calculée en utilisant la méthode du bilan de masse dans des mésocosmes HSSF matures alimentés avec un ruissellement agricole synthétique contenant du CAP pendant une période d'un mois. Les mésocosmes avec l’ajout de biochar se sont avérés très efficaces dans l’abattement du CAP (90 à 99%) et ils le sont restés tout au long de la période expérimentale. Cette efficacité est probablement due à la grande capacité d’adsorption du biochar, bien que ce mécanisme n’ait pas été directement mesuré. En revanche, l'abattement du CAP dans les mésocosmes plantés sans biochar était faible et limité et il n’y avait pas de différence entre les espèces, bien qu’elles aient eu des différences dans leur biomasse aérienne et leur taux d'évapotranspiration (ET). Cependant, les traitements plantés ont agi comme zone tampon, en atténuant la masse du CAP de l'influent et en la libérant lentement dans l'effluent. Le taux d'ET de Scirpus et Phragmites était plus élevé que celui de Sporobolus, ce qui s’est traduit par un meilleur effet tampon. Cette étude suggère que l'ajout de biochar au substrat HSSF TW est prometteur pour l'atténuation du CAP dans le ruissellement agricole, mais leur efficacité à long terme reste à être étudiée. Malgré tout, les TW devraient être utilisés comme un outil complémentaire, dans le cadre d'actions plus larges visant à réduire la pression des polluants sur les écosystèmes aquatiques. / Over the past decades, a wide variety of emergent pesticides, such as chlorantraniliprole (CAP), have been introduced despite the lack of in-depth knowledge of their ecotoxicological risk. Treatment wetlands (TWs) are environmentally friendly and sustainable technologies that have shown great potential to mitigate common agricultural pollutants, such as pesticides in runoff. The objective of this study was to optimize the use of the horizontal subsurface flow treatment wetlands (HSSF TWs) by determining a) the effect of biochar amendment to the substrate and b) the performance of three species of macrophytes (Phragmites australis subsp. americanus, Scirpus cyperinus and Sporobolus michauxianus) in CAP removal from agricultural runoff. The removal efficiency was calculated using the mass balance method in mature HSSF mesocosms fed with synthetic agricultural runoff containing CAP for a period of one month. Mesocosms with the addition of biochar were very effective in removing CAP (90-99%) and remained so throughout the experimental period. This efficiency is likely due to the high adsorption capacity of biochar, although this mechanism has not been directly measured. In contrast, CAP removal in mesocosms planted without biochar was low and limited and there was no difference between species, although there were differences in their above-ground biomass and their evapotranspiration (ET) rate. However, the planted mesocosms acted as buffer zones, reducing the CAP mass of the influent and slowly releasing it into the discharge. The ET rate of S. cyperinus and P. australis was higher than that of S. michauxianus, resulting in a better buffering effect. This study suggests that adding biochar to the HSSF TW substrate is promising for CAP attenuation in agricultural runoff, but their long-term effectiveness remains to be investigated. Nevertheless, TWs should be used as a complementary tool, as part of wider actions aimed at reducing the pressure of pollutants on aquatic ecosystems.

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