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Navegando Programa de Pós-graduação em Ciências Ambientais por Por Orientador "Ferreira Júnior, Laerte Guimarães"
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Item Morfometria e uso da terra da bacia hidrográfica do Rio do Coco e suas implicações sobre a produção e transporte de sedimentos(Universidade Federal de Goiás, 2017-03-31) Almeida, Rejane Freitas Benevides; Bayer, Maximiliano; http://lattes.cnpq.br/4552593148328465; Ferreira Júnior, Laerte Guimarães; http://lattes.cnpq.br/8647270006257055; Ferreira, Nilson Clementino; Faria, Karla Maria Silva de; Zancopé, Márcio Henrique de Campos; Silva Júnior, José Luiz CabralThis study aimed to evaluate the influence of morphometric aspects and land use in the areas of permanent preservation of watercourses on the production and transport of sediments in the Rio do Coco watershed. It is located on the right bank of the Araguaia River basin, in the state of Tocantins, between the municipalities of Caseara, Marianópolis do Tocantins, Divinópolis do Tocantins, Monte Santo, Paraíso do Tocantins, Chapada de Areia, Pium and Barrolândia. The first phase of the study consisted of compartmentalization and morphometric analysis of the basin, where it was verified the existence of regions (high basin) with natural characteristics indicative of greater susceptibilities that may potentiate sediment supply, pointing out the need of more effective planning of the use activities. The second phase was dedicated to evaluating the cover and the soil use of the Rio do Coco basin, in addition to identifying and quantifying the percentage of areas with land use conflicts in the areas of permanent preservation of water courses. For this purpose, the mapping of land cover and land use was carried out using images from Landsat 8 (2015) satellite. For the identification of PPAs buffers with buffer strips were created according to the limits defined in the legislation. The conflicts of land use in APP were measured after the overlap of the map generated in the classification and the PPA map, being verified for the entire basin 32.8% of areas with conflicts of use along the bodies of water and, although the sub-basins belonging to the region of the high basin are the regions with greater irregularities. The third and last phase of the thesis evaluated the production and transport of sediments in the Rio do Coco basin and its most representative sub-basins. This analysis was carried out by means of measurements of liquid and solid discharges in the Coco River and in the mouth of the channels of the main sub-basins. Measurements were initiated in November 2014 extending through April 2016 from bimonthly collections. The quantification of the solids load obeyed the methodology defined by Carvalho (2000b), and the flow measurements are performed using the following flow meters: ADV (Acoustic Doppler Velocimeter) FlowTracker and ADCP (Acoustic Doppler Current Profiler). The total discharge followed the method of Colby (1957) in Carvalho (2000a) and the specific production of sediments was analyzed based on the methodology of Carvalho (2008). From these analyzes it was possible to measure the volume of material transported by the main drainage channels of the basin, being proved that the region of the high basin is responsible for most of the sediments produced and transported in the water bodies. It should be noted, therefore, that this material has not arrived fully in the Araguaia River, part is being deposited along the canal, it is evident that in the basin there is an environment where production and transportation predominate and in another the accumulation. The results found in this phase of the research only reinforce the evidence observed in previous phases, where it was verified that the morphometric aspects are determinant in the sedimentological discharge of the basin, being the use and coverage of the soil considered maximizer of the whole process.Item Manejo e monitoramento de impactos sobre o ecossistema em áreas protegidas de cerrado: estrutura da vegetação, gramíneas exóticas e incêndios(Universidade Federal de Goiás, 2019-07-05) Batista, Flávia Regina de Queiroz; Ramos Neto, Mario Barroso; http://lattes.cnpq.br/7182178358444899; Ferreira Júnior, Laerte Guimarães; http://lattes.cnpq.br/8647270006257055; Ferreira, Laerte Guimarães; Faria, Karla Maria Silva de; Cianciaruso, Marcus Vinícius; Ferreira, Nilson Clementino; Taitson, GuilhermeThe Cerrado is the richest, perhaps the most threatened savannah in the world, and only 3% of its area is protected by law. These are extremely valuable and strategic areas for the conservation of the Cerrado, but suffer numerous external and internal pressures. Among the main management concerns for the Conservation Units (UC) of the Cerrado are fires and biological invasion. This work investigates how the interference of the management and the dynamics of the fire and the invasion of exotic grasses alter the phytophysiognomies of cerrado, and is divided in chapters that investigate respectively: 1) the difficulties in producing a map of sufficient accuracy to support studies of dynamics of vegetation structure; 2) the effectiveness of the current fire management system and the challenges of integrated fire management in the last two decades; 3) the invasion by exotic grasses and their relation with the topography of the terrain, tracks and roads in and around the study area. Landsat 8 images from a period of 5 years from 2013 were used and calculated for 5 different time intervals - monthly, inter-monthly, annual, yearly, quinquennial - sets of metrics based on 18 indices derived from reflectance values of the bands of these images besides the values of reflectance of the bands, data sampled in the field and semiautomatic classification for the mapping of the vegetation classes of the National Park of Emas (PNE). From a replicable model it was possible to elaborate a map with 89% accuracy and nine classes of phytophysiognomies, reducing the costs and the subjectivity of the manual work of data collection and posterior corrections. Using metrics elaborated from a digital elevation model and data of presence and absence of Urochloa sp on internal tracks and along the edges of the UC. Four models were tested using morphometric parameters, distances to tracks and roads in contrast to the presence or absence of the species. The results point to the importance of anthropic disturbances, terrain topography, and indicate that the force of water in its runoff is very relevant in establishing the species in new areas. In order to understand the spatial and temporal behavior of fire in the Emas National Park (PNE), the frequency of burnings for the different phytophysiognomies was analyzed, the correlation between the number of heat spots and the extent of the scars and the influence of the environmental variables surface, precipitation and accumulation of biomass). The scars of burned areas, heat sources, climatic variables - rainfall and temperature of the earth's surface (°C) - dry biomass surface and accumulated biomass for burned and unburned areas were analyzed. The annual peak of heat sources pointed with great accuracy to the occurrence of burnings in the PNE area, the number of outbreaks showed to be a good indicator of scar occurrence and size, the extent of area with dry biomass at categories 'very high' and 'critical' is a risk indicator of large fires and a reasonable predictor of areas that serve as a blockade to the spread of fires. The current fire management plan through firing and natural burning during the dry season has brought advances in fire prevention, but it is necessary to consider the use of prescribed controlled burns.Item Detecção automática de desmatamentos no bioma cerrado: desafios para o monitoramento sistemático(Universidade Federal de Goiás, 2018-03-13) Faria, Adriano Silva de; Araújo, Fernando Moreira de; http://lattes.cnpq.br/8681719274269970; Ferreira Júnior, Laerte Guimarães; http://lattes.cnpq.br/8647270006257055; Ferreira Júnior, Laerte Guimarães; Ferreira, Nilson Clementino; Silva, Elaine Barbosa daThe Cerrado biome has about 30% or 12,070 of the flora species cataloged in Brazil. Accelerated occupation and loss of biodiversity have made the Cerrado one of the 34 hotspots in the world. With a high index of endemism, about 30% (645) of the species that make up the list with some level of threat of extinction in Brazil are located in the Cerrado. The biome still has a remarkable climatic seasonality, with dry and rainy season. The replacement of Cerrado vegetation for anthropic uses intensified in the 1970s, basically for agricultural uses. Studies on climate change point to deforestation as one of the causes of greenhouse gas (GHG) emissions, motivating the government to create programs to monitor the coverage and use of land and removal of natural vegetation. Mappings indicate a reduction of vegetation of the Cerrado in 6% in the 11-year interval (PROBIO in 2002 with 60.5% and Cerrado TerraClass in 2013 with 54.5%). In this way, it makes necessary the annual monitoring, financing the actions of conservation for the biome. In order to understand the detection in the Cerrado conversion and to obtain information in a short time, it was decided to use the Integrated System of Deforestation Alerts (ISDA), since it is the only annual monitoring of the biome and has a low cost in relation to the others existing. SIAD was developed in Lapig and has provided conversion rates since 2003. In this way, the objective was to evaluate the potential and the limitations of detection of deforestation in the Cerrado using satellite images of moderate resolution and analysis of time series with reference to the SIAD. The efficiency of the reference map (i.e. PROBIO and TerraClass) was evaluated in relation to the amount of false deforestation generated. We attempted to understand the variation in the number of alerts generated as a function of rainfall seasonality from MODIS collections 5 and 6 (product MOD13Q1) and to analyze the seasonal behavior of deforestation alerts from 2015-2016 using the BFAST algorithm. Thus, the SIAD generated 101,902 deforestation alerts for 2015-2016 using the Cerrado TerraClass mapping and MODIS collection 6, of which 3% (3,185) were classified as deforestation by the visual inspection method. It was verified that the Cerrado TerraClass reference map generates less false deforestation than the PROBIO, and that, the collection 6 presents greater sensitivity of change in the vegetation in relation to the collection 5, contributing to the increase of false deforestation. The seasonality of precipitation is directly related to the number of alerts generated. However, the BFAST algorithm was effective in filtering the false positives, not presenting breaks in 16% of the alerts generated for 2015-2016, with 99% agreement with the visual inspection.Item Avaliação de áreas de pastagens a partir de bibliotecas espectrais, dados lidar e imagens aéreas(Universidade Federal de Goiás, 2020-01-07) Mesquita, Vinícius Vieira; Ferreira Júnior, Laerte Guimarães; shorturl.at/iPSU1; Ferreira Júnior, Laerte Guimarães; Ferreira, Nilson Clementino; Tyrone, RherisonGrasslands are important environments for global food security as they are responsible for the production of meat and milk from ruminant animals. Unfortunately, the negative consequences of the expansion of pasture areas is the loss of biodiversity, especially in the Brazilian Cerrado where more than 23% of natural vegetation has been converted to pasture. Thus, it is necessary to look for solutions to maintain the growth of food production without deforestation focusing on the recovery of degraded areas and intensification of use in underused places. Through hyperspectral data collected in the field, aerophotogrammetric data obtained by RPAS and laser pulses emitted by airborne LiDAR sensor, this work aims to evaluate the use of these data in pastures under different management and different seasonality conditions. The experiment area is the Rio Vermelho Basin (BHRV). In this region we were collected spectral data over 17 months in five pasture areas of 500 x 500 meters to compose a spectrum-temporal library. RPAS data were also collected in 2019 and LiDAR in 2015 and 2018 along a 50 km by 200 meters transect. The library built from spectral data was able to represent variations related to seasonality and management of pasture areas. The LiDAR point clouds on pastures were able to produce canopy height information faithful to the landscape observed in the field. The results obtained with RPAS proved to be insufficient to reach the objective, requiring more experiments to be usable. The spectro-temporal library formed exclusively by data sampled at pasture and the use of data from LiDAR showed a remarkable ability to describe the landscape and its nuances. However, further studies are still needed to better understand the results and validate the techniques.Item Dinâmica de ocupação, vulnerabilidades e cenários para a bacia hidrográfica do rio Vermelho, Goiás(Universidade Federal de Goiás, 2013-02-22) Vieira, Pedro Alves; Miziara, Fausto; Ferreira Júnior, Laerte Guimarães; http://lattes.cnpq.br/8647270006257055; Ferreira Júnior, Laerte Guimarães; Sano, Edson Eyji; Bayer, Maximiliano; Guimarães, Renato Fontes; Oliveira, Ivanilton José deThe historical process of occupation and land use in the Cerrado biome has been accompanied by different rates and conversion levels. Recent surveys indicate that about 50% of the original Cerrado cover has been already converted to large-scale agriculture. In Goiás, this process started with the mining activity, in the early XVIII century. However, the first governmental development policies start only in the early 40’s, under the govern of Getulio Vargas, and only in the 60’s, with the goals set by President Juscelino Kubitschek, became trully effective. In face of the historical land use dynamics, eventually over highly vulnerable areas, the Cerrado suffered a significant loss in environmental quality. An example in this direction is the medium Araguaia basin, which presents a stock of sandy sediments of about 200 million tons, in part fed by the upper Rio Vermelho basin, where sediment loss reaches 2 million tons a year. Within this context, this study, based on field, census, and orbital data (from different acquisition periods and with different resolutions), integrated and analyzed via GIS and scenario modelling techniques, pursued the identification, for the total area of the Rio Vermelho basin (nearly 11,000 km2), of different classes of natural vulnerability (relying on the mapping of entropy levels, as well as on tectonic and physiografic patterns), relatively to the occupation process, in four distinct periods (1976, 1987, 2002 e 2008). Approximately 65% of the basin area has been converted, which caused a severe environmental impact, affecting ~40% of the permanent protected areas (mainly around springs, lakes, and rivers), as well as ~9% of highly vulnerable areas. The occupation analysis for two distinct periods, i.e. 1976 (start) and 1987 (end), suggests that soil fertility and occupation fronts already established are the dominant factors controlling the basin fate, with new occupations being directed and concentrated along the main road network.