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Item Emprego de sensoriamento remoto nas estimativas de concentração de sedimentos em água(Universidade Federal de Goiás, 2019-09-24) Holdefer, Antônio Eliseu; Formiga, Klebber Teodomiro Martins; http://lattes.cnpq.br/0787413754235970; Formiga, Klebber Teodomiro Martins; Ferreira, Nilson Clementino; Souza, Saulo Bruno Silveira e; Santos, Felipe Correa Veloso dos; Medeiros, Antonio Marcos de MeloSuspended sediments in rivers and on the coastline affects the hydrological, geomorphological and ecological aspects of flood plains and deltas. Traditional SSC insitu measurement is most often challenging in terms of time, cost, qualified personnel, and space coverage. Remote satellite sensing offers a convenient way to cover large areas at reasonable intervals of time. The objective of this study is to develop an approach to the use of public accessible satellite images to quantify the concentration of suspended sediments (SSC) in Brazilian rivers, watersheds and coastline. In addition to obtaining historical trends, for a better understanding of the CSS variations that have occurred over the past three decades. The approach used in the articles present in this thesis makes use of indexes derived from the reflectance values of the spectral bands of the satellite images in order to estimate the value of SSC present in rivers, coast and watersheds, making use of values measured in situ for the calibration of such values. The present thesis consists of the introduction to the topic, methods and four articles, the first article makes a general approach to the current state of the art for the derivation of SSC values through indexes derived from the reflectance values of the spectral bands of satellite images. The second article makes use of SSC estimation techniques to study the sediment concentration variations in water along the Araguaia River. The third article makes a temporal analysis of SSC variations in the Brazilian basins in the last 32 years. The fourth article presents a new methodology for the temporal analysis of the SSC variations along the entire Brazilian coastline for the last 32 years. Among the main innovations present in this thesis we can highlight: 1) Estimation of SSC throughout the entire Brazilian territory, together with historical trends. 2) Use of LandSat family of terrestrial satellites to estimate the concentration of SSC for the entire Brazilian coast, at a distance of up to 50 km from the Brazilian coast, also with historical trends.Item Avaliação da disponibilidade hídrica superficial no estado de Goiás(Universidade Federal de Goiás, 2020-03-12) Honório, Michelle da Silva; Formiga, Klebber Teodomiro Martins; http://lattes.cnpq.br/0787413754235970 Nomes dos; Scalize, Paulo Sérgio; http://lattes.cnpq.br/0957896448117207; Scalize, Paulo Sérgio; Bezerra, Nolan Ribeiro; Ferreira, Nilson ClementinoBased on the principle that water resources are limited and vulnerable, associated with the use by a growing population, industrial and agricultural expansion, management in an integrated manner is necessary, with the use of preventing damage and ensuring the use of quality water and quantity for the present and future society. The issuance of grants in the state of Goiás for the use of state-owned waters is under the responsibility of the Secretaria de Estado de Meio Ambiente e Desenvolvimento Sustentável, which describes in the Resolução n° 09, de 04 de maio de 2005 the conditions and criteria for effecting the authorizations. In this process, knowledge of water availability is paramount, but obtaining hydrological information directly is not always possible and, in many situations, tools are needed to assist in obtaining this information, such as flow regionalization. So, this study had as main objective to evaluate water availability in surface catchment basins for public supply in the state of Goiás, through the comparison between the traditional method of flow regionalization and the method used by the water resources management agency in Goiás Of the 195 surface catchment basins analyzed, it was found that 27.7% have flows granted that exceed the flow that can be granted and/or exceed the reference flow present in 95% of the time. It was concluded that these catchment basins for public supply are in critical situations and that the grants, granted in these places, exert an excessive pressure on the springs, since the withdrawal of water is greater than allowed. As much as water availability estimates have been carried out using flow regionalization, these areas can be considered as priorities for the planning and management of water resources and for implementing actions based, for example, on payment for environmental services.Item A ocupação de áreas savânicas no Brasil e Moçambique(Universidade Federal de Goiás, 2020-07-15) Oliveira, Wellington Nunes de; Ferreira, Nilson Clementino; http://lattes.cnpq.br/6466969611652630; Ferreira, Nilson Clementino; Miziara, Fausto; Formiga, Klebber Teodomiro Martins; Ribeiro, Noely Vicente; Kopp, Katia AlcioneThe agricultural areas formation due to the growing demand for food and its pressure on ecosystems is a worldwide issue. Among these ecosystems, the savannah regions deserve special attention due to the accelerated degradation process that occurred in the last decades. In this context, through the use of geoprocessing tools, this thesis sought to perform a multitemporal analysis of the occupation of savanna environments in Brazil and Africa, considering the technological limits of orbital sensors, and also to estimate scenarios for the occupation of savanna areas in Mozambique. In Brazil, the Cerrado biome has a very consolidated occupation by agriculture, occupying about half of its geographical extension. On the African continent, there is another savanna area, also known as Miombo, which, although quite fragmented, is still less anthropized compared to the Cerrado, but with increases in the occurrences of deforestation and / or pyrogenic events. Through the mapping of land use and occupation it was possible to verify that the African Miombo has 77.86% of its native vegetation preserved, while the Cerrado has 53.48%. Specifically in Mozambique, one of the objects of study of this research, the coverage of remnants of native vegetation presented an average value of 62.25% of its preserved area. As for pyrogenic events, although the Cerrado and Miombo are ecosystems that have some phytophysiognomies adapted to fire, their use for the conversion of virgin areas for planting, and to stimulate the regrowth of pastures is quite harmful, causing several damages to biodiversity. In the analyzed period, the scars of fires represented approximately 92,500 km2 and 721,900 km2, respectively, for Cerrado and Miombo. For the estimation of land use and occupation scenarios in Mozambique, the potential distribution model was used, through Maxent (Maximum Entropy), which presented a predictive scenario for the year 2022 of 51.26% of preserved native vegetation. Whether through multitemporal analysis or the projection of scenarios, it is possible to note the acceleration of the conversion of native vegetation cover into agricultural crops and pastures in the savannas. In this way, this study collaborates with the generation of a database to better represent the conservation panorama, as well as the degree of anthropization suffered by these savannas.