Navegando por Assunto "SRTM"

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Acesso aberto (Open Access)
Análise de imagens Landsat ETM, Radarsat-1 e modelos numéricos de terreno para o mapeamento dos índices de sensibilidade ambiental ao derramamento de óleo na costa de manguezais do nordeste do Pará
(Universidade Federal do Pará, 2006) BOULHOSA, Messiana Beatriz Malato; SOUZA FILHO, Pedro Walfir Martins e; http://lattes.cnpq.br/3282736820907252
Accidents related to exploration and oil transport are a threat to coast zones araund the world. Oil spills are an ecological disaster that may cause irreparable damage to the environment affecting living beings that live in these coast zones and also the local economy. Characterizing coast environments is very complex because of the many limiting factors during the mapping process. When it comes to humid tropical environment, like in Pará northeast coast, it gets worse because this area is typically dominated by macro tide. First of all, the macro tide plain creates low areas where informations about the relief are, most of times, scarce and the plain metric representation is dominant. Secondly, the tide variations with its vertical and horizontal moving produces strong changes on the sediment coast environment limits. Thirdly, the geomorphological modifications in the coast areas are intense and fast. Towards this context, the objective of this master’s degree dissertation is to create a map of the coast environment and a rating map of the environmental sensitivity about the oil spills in a certain part of Pará state northeast coast. The methodology consisted on processing digital images from remote sensors in the range of optical (Landsat ETM +7) and microwave (RADARSAT–1 Wide-1) associated to data from the SRTM (shuttle radar topographic mission) digital model of elevation, and to the field data collected in SIG (geographical information system) environment, providing an integrated analysis of the spectral, geomorphological, altimetrical and sedimentological characteristics of the coastal environments in cartographic georeferenced bases. The most important results of this dissertation allowed: 1) The evaluation of the potential of the images Landsat ETM +7, RADARSAT-1 and of the multi sensors fusion products used for identifying the coastal environment and the Environment Sensitivity Rates (ISA) of oil spills in this areas 2) Recognizing and describing five main morphological unities and fourteen sub unities: Coastal Plateau, Tide Plain, Coastal Plain and Alluvial Plain 3) Identifying and classifying eight unities of Environmental Sensitivity Rates (ISA) for the Amazon coast zone which are: ISA 1B – support wall; ISA 3B – exposed scarps with declivity to the sand; ISA 9B – sand bank and plains of tidal vegetable mudflats; ISA 9C – hypersalt herbaceous fields, ISA 10A – salt and salobre herbaceous fields; ISA10C – Mangrove; ISA 10D – Lea; 5) creation of the Environmental Sensitivity Rates map to oil spill of the studied area. The using of remote sensors techniques and SIG proved to be an important tool for recognizing and analyzing coast environments and for generating maps to coast environments and to environmental sensitivity rates to oil spills in the northeast coast of Pará.
Acesso aberto (Open Access)
Mapeamento dos parâmetros florísticos e estruturais de floresta de mangue com dados LIDAR e SRTM
(Universidade Federal do Pará, 2014-06-24) ABREU, Maria Rafaela Braga Salum de; FERNANDES, Marcus Emanuel Barroncas; http://lattes.cnpq.br/8943067124521530; SOUZA FILHO, Pedro Walfir Martins e; http://lattes.cnpq.br/3282736820907252
This study estimated the floristic and structural parameters (height, diameter at breast height - DBH and biomass) of mangrove from remote sensing data Laser Detection and Range (LIDAR), Shuttle Radar Topography Mission SRTM and orthophoto on Guarás Island, located 30 km from the mouth of the Amazon River. It was used data from LIDAR, SRTM and ortophotos during overflights. With the orthophoto data it was produced a map of Geobotanic units including only the mangrove area. It was performed the orthometric height correction and the point clouds was interpolated by nearest neighbor Technique, generating Digital Elevation Model (DEM) LIDAR (full points) with RMSE of 0.88 cm and using a computer language it was statistically separated the information of the last pulse of the surface as known as ground points. Thus data was interpolated by kriging method which was subsequently subtracted from the DEM. With Digital Model Height (DMV) values it was defined and selected the study sites and it was measured the trees in three categories: upside, intermediate and emerging trees. Than it was measured DBH and height in these places. 212 samples were collected and it was calculated the RMSE between the heights of the LIDAR and field, that resulted in a RMSE of 1.10 m. The chosen model to cross the information of LIDAR and field was the linear model whit R 2 = 91% and RMSE = 0.98 cm and for DBH and height field it was chosen the logarithmic model with R 2 = 74.1%. In the results of calibration of SRTM data the logarithmic model was also the most appropriate, in the relation of average height with SRTM there was a R 2 = 91% and RMSE of 2.2 m and to avarage DAP with SRTM the R 2 value was 88% and RMSE of 2.2 cm. With an inventory, biomass per specie data was estimated from field and it was produced maps of biomass per species from LIDAR, corrected SRTM and ortophotos.