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Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-04-25T22:48:13Z No. of bitstreams: 1 Dissertação Andre Pereira Dias.pdf: 4828090 bytes, checksum: 3d6bf1d9b3f9e5374b0309ddde97163f (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-05-16T14:28:27Z (GMT) No. of bitstreams: 1 Dissertação Andre Pereira Dias.pdf: 4828090 bytes, checksum: 3d6bf1d9b3f9e5374b0309ddde97163f (MD5) / Made available in DSpace on 2018-05-16T14:28:27Z (GMT). No. of bitstreams: 1 Dissertação Andre Pereira Dias.pdf: 4828090 bytes, checksum: 3d6bf1d9b3f9e5374b0309ddde97163f (MD5) Previous issue date: 2014-02-20 / CAPES / A demanda por água é uma preocupação recorrente em várias regiões do planeta. O Brasil, e em especial a região do Médio Araguaia, é uma região do planeta onde esse recurso é abundante, e também um dos que tem menos ações voltadas para a conservação e uso racional de seus recursos naturais. A degradação do macrossistema de áreas úmidas do Médio Araguaia vem ocorrendo a partir dos anos 70 de forma acelerada. O presente estudo visa servir de subsidio para políticas ambientais de fiscalização, recuperação e conservação, de forma a garantir as funções ecológicas deste importante sistema aquático-terrestre, onde para qualquer planejamento é necessário o conhecimento sobre a abrangência e limites da região estudada. Sendo assim, a delimitação da superfície máxima inundável das áreas úmidas da planície de inundação da Bacia do Médio Araguaia, considerando-se as épocas de maior inundação, se constitui como o esforço principal desse trabalho. Para tanto foram utilizadas técnicas de sensoriamento remoto aplicadas a imagens multitemporais do sensor TM do satélite LANDSAT 5, onde, através dos índices gerados pela transformação Tasseled Cap (TC), foram extraídas as amostras de treinamento que permitiram realizar uma classificação supervisionada através do algoritmo Support Vector Machine (SVM). Paralelamente, foi gerado um modelo HAND (Height Above the Neareast Drainage) utilizando o modelo digital de elevação SRTM (Shuttle Radar Topography Mission). O cruzamento das informações obtidas pela classificação com o modelo hidrologicamente consistente HAND-SRTM permitiu estimar as áreas úmidas não detectadas pela classificação, tais como áreas alagadas sob densa cobertura vegetacional. Esses procedimentos permitiram delinear os limites máximos das áreas passíveis de inundação em época de cheia, que recobrem uma extensão de 88.119 km², cerca de 23% da área total da bacia do Médio Araguaia. / The demand for water is of great concern in many regions of the planet. In Brazil, particularly in the Araguaia region, water is an abundant resource, but is subject to poor conservation and water use policies. The degradation of the macrosystem of wetlands in the middle Araguaia has been taking place since the 1970s in an accelerated manner. This study aims to provide subsidy in the formulation of environmental policies for monitoring, recovery and conservation, which ensure the ecological functions provided by these important wetlands. In order to achieve that, the knowledge of the boundaries of the area to be studied is necessary. Thus, the main purpose of this work is the delimitation of the maximum surface likely to flood in the middle Araguaia basin, considering seasons of larger floods. Remote sensing techniques were used in multitemporal images from the LANDSAT 5 TM sensor, for the flood season. Through indexes generated by the Tasseled Cap (TC) transformation, areas of interest were obtained from the landscape elements, such as vegetation, soil, water, and wetlands. From training sample sets, a supervised classification was obtained using the Support Vector Machine (SVM) algorithm. In addition, a HAND (Height Above the Nearest Drainage) model was created using the Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM). The classes associated with humidity, resulting from the classification, were correlated to the altimetric classes obtained from the hydrologically consistent HAND-SRTM. Such procedures allowed the delineation of the maximum boundary of areas likely to flood during flood seasons, which cover 88,119 km² - around 23% - of the Médio Araguaia basin.

The problem of whether Landsat 7 data could be used to delineate areas prone to mass movement, particularly debris flows and landslides, was examined using three techniques: change detection in NDVI (Normalized Difference Vegetation Index), change detection in band 5, and the tasseled cap transformation. These techniques were applied to areas that had recently experienced mass movement: Layton, Davis County and Alpine, Spanish Fork Canyon and Santaquin, Utah County. No distinctive spectral characteristics were found with any of these techniques with two possible explanations: 1. That despite improved spatial resolution in Landat 7 over its predecessors and improved digital image processing capabilities, the resolution is still too low to detect these characteristics or 2. That the aspects of a slope that make it prone to mass movement are undetectable at any resolution by remote sensing. Change detection in NDVI examined if areas that remained unchanged (defined as < 5% change) between August 14, 1999 and October 17, 1999 correlated to areas that are prone to mass movement. There was no correlation. Change detection in band 5 was examined between August 14, 1999 and October 17, 1999, October 17, 1999 and May 28, 2000, and August 14, 1999 and May 28, 2000. An interesting result is that the Shurtz Lake and Thistle landslides (Spanish Fork Canyon) showed changes of greater than 30% during August 14, 1999 - October 17, 1999 and October 17, 1999 - May 28, 2000. These changes were limited to these landslides and not seen in abundance in surrounding areas. A similar localization of 30% change was seen in the Cedar Bench landslide (Layton) for the same time periods. There were no other correlations. The tasseled cap ransformation shows areas of dominate greenness, soil brightness or wetness. None of these factors had distinctive patterns in the areas studied when compared to surrounding, mass movement-prone areas so no conclusions can be drawn about the utility of the tasseled cap transformation as it relates to areas of potential mass movement.