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Navegando Programa de Pós-graduação em Ciências Ambientais por Por Orientador "Ferreira Junior, Laerte Guimarães"
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Item Avaliação da área queimadas no bioma cerrado: proposições para o monitoramento e conversação(Universidade Federal de Goiás, 2015-03-03) Araújo, Fernando Moreira de; Ferreira Junior, Laerte Guimarães; http://lattes.cnpq.br/8647270006257055Fire is an important ecological and environmental disturbance phenomenon in the Cerrado biome, which is influenced by climatic, ecological, cultural and economic factors. Burning biomass promotes change in the structure and composition of the soil, accelerates the erosion and sedimentation processes, promotes seed germination, renewal of grasses and releases large amounts of trace gases and aerosols into the atmosphere. This research seeks to understand the location patterns and the recurrence of burned areas to the Cerrado biome according to their different geographical regions from the land cover and land use class, and climatic variables. In particular, we evaluated quantitatively the performance of the MODIS MCD45A1 product for the Cerrado biome, in accordance with the different land use and land cover classes depending on the landscape, using as reference 130 randomly selected burned area polygons, and four randomly selected medium resolution orbital images, both from the month of September. In addition, we analyzed the burned areas spatial and temporal patterns in Brazil, considering both the territorial limits of the six biomes (i.e. Amazônia, Caatinga, Cerado, Mata Atlântica, Pampa and Pantanal) and their main land cover and land use classes (PROBIO MMA). At last, for burned areas greater than 2 km², we evaluated their patterns (spatial and temporal) and frequency of recurrence (burned areas that intersect more than 50%), as well as their interanual and seasonal climatic variations from vegetation index (EVI), precipitation (TRMM) and evapotranspiration (MOD16) images. These images were analyzed in association with the four groups of recurrence (burned areas with recurrence every four years) to determine the different burning regimes and the pre and post burning vegetation responses. The MCD45A1 polygons (September) had good relationship with the reference mapping (Landsat base) (r² = 0.92) and also with the hotspots (MOD14 and MYD14 - monthly data) (r² = 0.89). The omission error found is high, but this is associated with landscape structure patterns, as found for the four reference images. The Product MCD45A1 even with spatial and temporal limitations promotes temporal mapping consistency and provides understanding the behavior and impacts of the burned on the Cerrado landscape. Among the Brazilian biomes, Cerrado is the one with the highest record of fires between 2002 and 2010 (73%), followed by Amazon (14%), while 81% of the records of the burned areas occur on the remnant vegetation cover class. The records of the burning recurrences in the Cerrado focus on the remnant class, 59% whereas the frequency of recurrence presented a higher proportion up to 3 times for the period 2000-2013. For the four groups of recurrences analyzed after the first fire record, 2002, the vegetative vigor records declines, especially after 2010, on average 4% for the remnant classes and 3.5% for the anthropogenic. The minimum distance between the fragments presents that 42% of recurrences analyzed are between 1-2 kilometers, providing greatest spatial concentration.Item Estimativas satelitárias de precipitação sobre o bioma cerrado: possibilidades e perspectivas(Universidade Federal de Goiás, 2016-04-18) Farias, Sylvia Elena de Marques; Luiz, Gislaine Cristina; http://lattes.cnpq.br/4310433384519387; Ferreira Junior, Laerte Guimarães; http://lattes.cnpq.br/8647270006257055; Ferreira Júnior, Laerte Guimarães; Ferreira, Nilson Clementino; Faria, Karla Maria Silva; Oliveira, Ivanilton José de; Griebeler, Nori PauloThe Brazilian savanna is the second largest biome, covering an approximate area of 21% of the national territory. Among other factors, the rainfall favored the activities of agribusiness and hydro-dependent activities of the climate pattern of rainfall. However, the biome is complex climatologically and rainfall network is sparse or poorly distributed. In this sense, this study sought to evaluate the precipitation estimates of the Savanna. The main results of this thesis are: a) by the need to assess the rainfall pattern on the Savanna it was found that the rains are caused due to phenomena of weather and climate that operate seasonally, featuring the region by dry winters, from May to August, and rainy summers, from September to April. A deficit above -5,0 mm.mes-1 is observed between May and June, while the excess water, the rainy season can reach 240,0 mm.mes-1; b) given the complexity rainfall observed in the biome, statistical tests showed that version 7 algorithm was more accurate to estimate precipitation. As for the regions of the state inserted in the biome, Goiás presented the highest value as the Pearson correlation, 0,99. Estimates between area and pixel showed that the satellite estimates are consistent with the observations. Considering the ability of estimates of the annual and seasonal pattern, the precipitation anomalies reproduce the variability of dry and wet periods. The estimate for the year 2009, under the influence of the beginning of a moderate El Nino, played a rainy year throughout the Savanna. Conversely, 2007, characterized by end of an El Nino low intensity, reproduced a dry year; c) Analysis of Main Components (ACP) were characterized by the three most significant factors explaining 97,5% of the total variance of monthly precipitation data both for Brazil and for the Savanna. The CP1 varies linearly indicating that it explains both the Savanna as to Brazil the annual variation in rainfall. The CP2 brand significantly seasonality between Brazil and the Savanna. The CP3 varies significantly between characteristic months due to seasonality. The results suggest that the satellite rainfall estimates, version (3B43), are accurate on a complex and extensive biome as the Savanna.Item Monitoramento ambiental da superfície da terra utilizando dados de satélite de órbita geoestacionária: estudo de caso com o meteosat second generation(Universidade Federal de Goiás, 2018-03-20) Silveira Junior, Carlos Roberto da; Silva, Bernardo Barbosa da; http://lattes.cnpq.br/8285693170429747; Ferreira Junior, Laerte Guimarães; http://lattes.cnpq.br/8647270006257055; Ferreira Junior, Laerte Guimarães; Ferreira, Nilson Clementino; Luiz, Gislaine Cristina; Oliveira, Ivanilton José de; Ferreira, Manuel EduardoSatellites of geostationary orbit, commonly used for meteorological monitoring, provide, in new series, the possibility of environmental monitoring of the vegetation, having the advantage of greater temporal resolution, when compared to polar orbiting satellite data. However, it is necessary to know the characteristics and limitations of the data in order to obtain the biophysical indicators. Therefore, the purpose of this work is to investigate and to know the potential of environmental indicators to monitor the surface of the earth from geostationary orbit satellite data, specifically Meteosat-10 of the MSG (Meteosat Second Generation) series, with a view to assess their temporal and spatial characteristics. In order to do so, we sought to identify the inherent challenges for obtaining biophysical indicators for Brazil, which has as main limitation the high viewing angle. As well as, analyzing the results of correction techniques (geometric and atmospheric) and band fusion to increase the correlation of NDVI (Normalized Difference Vegetation Index) with MODIS (Moderate Resolution Imaging Spectroradiometer). In order to identify the potential of the data, the NDVI and NDWI (Normalized Difference Water Index) indicators were used to monitor the environmental seasonality in the basin scale. The study database period was from 2013 to 2015. As a result the NDVI MSG, obtained in the interval from 10:00 to 12:00 am, presents a high correlation (p> 0.8) with the MOD09, being able to to obtain an image about the state of Goiás with 95% coverage of pixels in the interval of 12 days, while the MOD09 obtains in the interval of 16 days. However, the MSG cloud mask presents a high percentage of error (21%), showing cloud when the MOD09 pixels mark the entire area as cloud-free. The use of the panchromatic band in the band fusion operation did not add to the results. Likewise, the geometric correction is a fine adjustment that, in these analyzes, did not present an increase in the correlation of the data. On the other hand, the atmospheric correction maintains the correlation of the data and increases the value of the NDVI, approaching more to the value NDVI MODIS. In an analysis of major components and unsupervised classification the NDVI MSG was superior to NDVI MOD13, with substantial agreement for annual agriculture (K = 0.73) and considerable for pasture (K = 0.35) and natural vegetation (K = 0, 34). By analyzing the seasonality of river basins, one can identify and understand seasonal patterns in different regions and classes of use. The NDVI and NDWI presented a higher correlation with the precipitation of two months ago (r > 0.84) and high correlation with each other (r > 0.94), with NDWI being more sensitive to the abstraction of seasonal behavior, allowing identification tendencies in some basin of Goias state. The results demonstrate the potential of biophysical vegetation indicators from geostationary satellite Meteosat-10 to monitor the land cover.