National Institute for Space Research
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Avaliação dos dados de chuva mensal para a região Amazônica oriundos do satélite Tropical Rainfall Measuring Mission (TRMM) produto 3b43 versões 6 e 7 para o período de 1998 a 2010
No full textThe estimation of components of the water cycle by satellite remote sensing plays an important role particularly in areas where the densities of ground level meteorological stations are sparse. In this study, we evaluated the accuracy of versions 6 and 7 of the product 3B43 from the Tropical Rainfall Measuring Mission (TRMM) satellite. The data derived from the TRMM satellite was compared with 33 rainfall gauge stations, derived from the National Institute for Meteorology (INMET). Data was selected to cover different parts of the Brazilian Legal Amazon. The data used for this study covers monthly time series from January 1998 to December 2010. A sample in the TRMM data was acquired for the location of each field station, and statistical analysis were carried out. The results showed that the TRMM product 3B43 tends to overestimate low rainfall and underestimate high rainfall. Both versions of the TRMM product explain 76% of the rainfall variability measured by the rain gauges stations (p<0.001). No clear spatial bias was observed for areas where the product presents higher Root Mean Square Error (RMSE) in relation to the rain gauges. Nonetheless, there seems to be a better performance of the TRMM in areas with higher seasonality, in the cerrado region. The next steps will be to include more field data for covering larger areas of the cerrado, and also include the other regions of the Brazilian biomes.Pages: 6743-675
Mapeamento mineral de solos tropicais em áreas degradadas por meio de imagens Aster
No full textDesertification processes have often been described in the southwest of Piaui, state of Brazil. The area with intense rocks and sediments exposure is localized around Gilbués and includes the cities of Barreiras do Piauí, Corrente, São Gonçalo do Gurguéia, Gilbués and Monte Alegre do Piauí and Riacho Frio. This region, recognized as one of four Desertification Centers from Brazil, has a strong environment and subsistence economy impairment due to the intensity of land degradation. Exposed surfaces match to sanded group rocks, corresponding to the beginning of the Cretaceous Age of Bacia do São Francisco, and represent pelites (mudstones and siltstones) and psalmists (sandstones) rich in clayminerals and ferruginous constituents. Below this rock formation is the Group Urucuia of the end of Cretaceous age, whose transition is marked groundwater zone. As multispectral remote sensing based on ASTER has successfully mapped the occurrence of clay minerals, in this study we opted to use the bands and/or ranges: from visible (visible - VIS) (0. 0.52 to 0., 69 μm ), NIR (near Infrared - NIR) (0. 0.78 to 0., 86 mm) and short wave infrared (Short wave infrared - SWIR) (1., 3 to 2 mM., 5 mm), discriminately. The aims of this study are: to map minerals exposed on exposed land area included in the Desertification Center of Gilbués and analyze the correlation of minerals mapped with data previously collected in the field and laboratory. We used the Ratio Bands operation and main Components Analysis to characterize the differences between spectral behaviors of different minerals, allowing them to discriminate on ASTER images. As a result it was identified in soils, in study area, minerals such as hematite, goethite, kaolinite and montmorillonite, whose spatial distribution has a clear relation with relief, pedogenesis, erosion processes.Pages: 1426-143
Quantificação e análise espacial dos focos de calor no Parque Nacional da Chapada Diamantina - BA
No full textFires in vegetation are pointed out as one of the main factors that impact and threaten the conservation of biodiversity in environmental systems. In Brazil, in the state of Bahia, Chapada Diamantina is one of the most affected region by constant burning, requiring huge investment of financial resources to fight the fires. Hotspots data detected by satellite sensors have been used to identify areas of occurrence of fires. From these data, estimates are made about the possible location and extent of affected areas, highlighting the temporal / spatial dynamic of fires. This study aimed to analyze the spatial behavior of hotspots between the years 2000 to 2011 in the National Park of Chapada Diamantina, in order to identify the areas of greatest intensity of fire occurrence obtained with the aid of Kernel intensity estimation. To this end, was made a survey of georeferenced hotspots existing into the park, organized a database, and then, in a GIS environment, modeled the distribution pattern of the set of points. According to the analyzed data, about 439 hotspots were detected by sensors aboard NOAA satellites - NOAA 12 and - 15 in the last 12 years within the park boundaries. It was found that the year of higher incidence of hot spots in the park was in 2008, when 243 focuses were detected. The number of hotspots recorded in 2008 represents about 55% of the total. It was found that 245 of the 439 spots detected were in the east border of the city of Mucugê (about 56%).Pages: 6969-697
Uso de Imagens do Satélite TRMM para Quantificação do Regime de Chuvas e Nebulosidade no Bioma Cerrado, Brasil
No full textOne of the methods to monitor the current rainfall, and possible global climate changes (natural or human induced changes), is through orbital remote sensing techniques. The TRMM satellite - Tropical Rainfall Measuring Mission is one of these new generation sensors, which provides monthly precipitation data of the world. The main objective of this paper was to analyze the rainfall dynamic in Cerrado, a threatened and degraded savanna area in Brazil by the agricultural expansion, through a TRMM time-series in the period from 2000 to 2010. Data analysis were performed in a Geographic Information System (GIS) environment In general, both in the dry and in the rainy season, there was a predominance of the lower classes of precipitation, consistent with the climatic characteristics of this biome, with restricted areas with a higher volume of rain. The effects of El Niño and La Niña tend to be less pronounced in the Cerrado; nevertheless, these phenomena may be related to prolonged dry seasons observed in this study. In the other hand, the Atlantic Polar Front (APF) may explain the differences in rainfall regimes found in the study area and are expressed in the climatic diversity of the country. Still based on the literature, by observing the precipitation in the Cerrado, the greatest rainfall occurrence is concentrated in the period from November to March, due to increased activity of the Equatorial Continental air mass (MCE), composed of moist air masses with higher temperatures, causing heavy rainfall in the summer.Pages: 8661-866
A geração de ortofoto de fachada de bens patrimoniais
No full textThe aim of this paper is to generate orthophoto of the main facade of the Igreja de Nossa Senhora dos Prazeres in Jaboatão Guararapes, PE, Brasil. In the computer program PhotoModeler Scanner, version 6, is processed in the camera calibration parameters which will fix the photographs, the unique codes that serve to guide overseas. The outer and inner guidance: relative and absolute complete the patching process then the photographs will be generated orthophoto. It is noteworthy that the external guidance is required criteria to create one reference photographs, in view of the impossibility of setting targets in all details of the geometry of the facade. To achieve the research objective will be obtained photographs converged within walking distance of the main facade. The orthophoto that helps professionals design and preservation of historical sites and monuments can do their jobs quickly and accurately with the use of available resources and low cost. Finally, it is recommended a survey to analyze the qualities of the data.Pages: 1990-199
Caracterização de um ambiente fragmentado no município de Lavras, MG utilizando métricas de paisagem
No full textAtlantic Rainforest and Cerrado are two of the most threated biomes of the world. We have just a few representations of these biomes and the most part of remaining are little fragments inserted into an anthropic mosaic. The objective of this work was analyzing landscape cover from semi-deciduous forest, a transition area from Atlantic Rainforest to Cerrado in municipality of Lavras, in Minas Gerais state. We found that Lavras is a fragmented area with the most of landscape cover corresponding of native vegetation (41%) followed by pastures (30,69 %). The area is dominated by anthropic pressure with most of native vegetation corresponding by little fragments (< 20 ha) and doesn´t have a continuous of native vegetation. Coffee has also an important representation on analyzed area (3,84 %), mainly in northeast region, and has an important function in maintaining a shrubby matrix. Shrubby areas can improve the matrix quality for forest species. The area contains a lot of corridors of native vegetation that can connect areas that were isolated in past and can function like functional corridor for wildlife. The buffers analyses showed us that the fragmentation is similar at all landscape. This characterizes the region like an anthropized area with reduced habitats to species persistence.Pages: 3390-339
Padrões de Refletância Espectral e de Temperatura das Áreas Queimadas para o bioma Cerrado
No full textThe Cerrado biome in relation to the others Brazilian biomes (Amazônia, Caatinga, Mata Atlântica, Pampa and Pantanal) is the most affect by burns. The fires have several consequences for the biome, as the increasing of temperature, decreasing rainfall, genetic impoverishment of natural species, increases the risk of respiratory diseases and others. To comprehension of the burn behavior that occur at Cerrado in September of 2011, and the period pre (April) and pos-fire (October), we used the MOD09A1 products (spectral reflectance) and MOD11A2 (surface temperature). The results demonstrates that 62% of burnt areas recorded in September 2011 are located in the northern region of the Cerrado, while 38% in the southern region with the largest economic and industrial development. During the burn (September) were recorded the lowest values of spectral reflectance and higher surface temperature for the classes of agriculture, pasture and remnant. However, for the periods pre and pos-fire the remaining vegetation had the lowest values for both variables.Pages: 1266-127
Uso da geotecnologia para elaboração de material didático-pedagógico para educação socio-ambiental nos municípios da Grande Dourados-MS
No full textThis study aimed to devise a geoenvironmental atlas of the municipalities that make up the Greater Dourados, using the tools of Geotechnology, especially the resources and techniques of geographic information system and remote sensing for obtaining and processing of spatial date. This atlas didactic-pedagogic subsidized the Environmental Education Program extension within the Greater Dourados (ESAT-GD), illustrating the current situation of geoenvironmental the region. To achieve the same, the mapping and characterization focused on the spatial area consists of seven counties that belong to the Greater Dourados, the thematic maps were prepared with the use of Geographic Information System (GIS) and remote sensing products, has the implementation of geographic datebase, as well as the storage and processing of remote sensing products that resulted in the series of thematic mapping needed to produce the atlas didactic, were performed using the software SPRING. Thus it was found that the geographic database, implemented as storage platform of thematic information, if configured as a repository of information geoenvironmental municipalities, and compatibility between systems of projection and datum, adopted for this base date, with the cartographic standards officers allowed to share your information with other institutions that need their referrals, so it was considered that the methodology adopted allowed obtaining positive results regarding the purpose of preparing a pedagogical-didactic material of a descriptive nature that expressed a characterization of various aspects of this geographical region.Pages: 4396-440
Seleção de atributos em imagens AVIRIS para mapeamento de uma área do Pantanal Brasileiro
No full textThe Brazilian Pantanal is known for its unique environment, which comprises a high fauna and flora biodiversity. For this reason, ecological research on these wetlands are so important for a better understand and monitoring of their dynamics. Hyperspectral remote sensing is a potential tool for land cover mapping using classification techniques. As a result of the large data dimensionality and depending on the classification technique selected to be used for mapping purposes, feature selection may be necessary to avoid the Hughes effect. In this study, we tested two algorithms for feature selection of the Airborne Visible Infrared Imaging SpectroRadiometer (AVIRIS) bands in the Pantanal wetlands. The two algorithms are part of the Waikato Environment for Knowledge Analysis (WEKA): the Correlation based Feature Selection (CFS) and the Chi-squared Attribute Evaluation (CSEA). Additionally, a new algorithm entitled Charged System Search (CSS) was experimented. The selected bands of the AVIRIS sensor were used as input for Maximum likelihood supervised classification to compare the performance of the three feature selection techniques. Z test results showed statistically significant differences between the Kappa values obtained from the use of the set of bands selected from CFS, CSS and CSEA algorithms, with the first two approaches providing better results than the CSEA procedure. As a whole, the use of the total set of AVIRIS bands did not result in a significant Hughes effect.Pages: 2266-227
Análise fisiográfica da Microbacia Hidrográfica Dois Córregos, Selvíria - MS, Brasil
No full textIt is known that a watershed is a complex system and is influenced by internal and external factors that may affect its various equilibrium relationships, and possibly lead to its degradation. This study aimed to determine the physiographic parameters of the micro watershed Dois Corregos, in order to provide information for planning and management of water resources in this watershed. Spring 5.1 software was used, for the calculation of physiographic parameters of the studied area. Analyzing the results of this study, it was found that the Dois Corregos micro watershed is not liable to flooding due to its more elongated shape. With respect to drainage density, the area of study obtained a value of 0.74 km/km2 being classified as poor and unlikely to natural erosion processes.Pages: 4467-447