National Institute for Space Research
Biblioteca Digital da Memória Científica do INPENot a member yet
6175 research outputs found
Sort by
Avaliação da supressão da vegetação e aumento da temperatura em áreas agrícolas do Oeste Baiano entre os anos de 1990 e 2010 por meio dos dados LANDSAT/TM
No full textThe increase in agricultural production in Western Bahia from the 80s has promoted changes in the remnants of the Cerrado biome. It is of great importance for studies that analyze the implications of increase agricultures and consequent alteration of local environmental characteristics. The advancement of technology, the diffusion of satellite images and digital processing tools intensified the relevance of remote sensing, making its use essential for evaluation of environmental impacts. This study aims to determine the temperature change due to the loss of native vegetation in areas of greatest adençamento agricultural and water bodies present in the main cities of the west of Bahia. In this area, the level of change in vegetation also is modifying the behavior of sediment accumulation, a phenomenon that also shows the temperature variation of the rivers. To produce the study used remote sensing techniques in imaging the TM / LANDSAT 5, with production of NDVI image and temperature in degrees Celsius image, to compare the relationship of these products between the years 1990 and 2010. The results showed it is possible to use data from thermal band to the environmental assessment and thermal alteration of the Cerrado biome.Pages: 1458-146
Comparação entre parâmetros morfométricos de bacias hidrográficas gerados por dados SRTM e ASTER GDEM: estudo de caso para bacias do Vale do Jequitinhonha-MG
No full textThis study compared the influence of image resolution SRTM and ASTER in morphometric analysis of five sub-basins of the river Jequitinhonha: Ribeirão Caraíbas, Ribeirão Ilha do Pão, Ribeirão Prates, Ribeirão Pasmado e Ribeirão Santo Antônio. The hydrography of the sub-basins was extracted from both types of images. Morphometric variables were calculated from the sub-basins, including: perimeter, area, coefficient of compactness, total length of canals, slope and drainage density. It was possible to visualize the areas and perimeters of the sub-basins were observed did not differ significantly. Compactness all coefficient values obtained were higher for unit 1, indicating that the sub-basins are elongated shape. Comparing the lengths of channels between the SRTM and ASTER images, we can see a considerable difference. The values obtained in ASTER images tend to be higher, ie, due to a better resolution of the image resulting in a more detailed delineation of the basins. The results of the drainage density calculations show that the sub-watersheds have low density. It is notable that generate high resolution images in more detail in the definition of basins, however, in some cases, these details large, difficult to visualize and understand the basin generated.Pages: 5443-545
Expansão do cultivo da cana-de-açúcar em inconformidade ambiental com as áreas de preservação permanente de cursos d'água entre as safras 2004/2005 a 2009/2010
No full textThe cultivated sugarcane area in Brazil is estimated around 8 million hectares, occupying 60% of the São Paulo State land area. Otherwise, the Permanente Preservation Areas in water courses occupies approximately 4.48 million hectares in the same State, according to the CONAMA Resolutions (N° 302 and 303). The goal of this work is to analyze the expansion of the sugarcane from the crop years of 2004/2005 to 2009/2010 on environmental nonconformity with the Permanent Preservation Areas in water courses through the remote sensing images.Pages: 6448-645
Servidor de mapas para o gerenciamento espaço-temporal da produtividade de milho no Brasil
No full textThe increasing use of geotechnology has enabled the cartographic databases production that gather great diversity of multidisciplinary geographic information. However, the publication or availability of this information to society in general is still poor, mainly due to lack of funds for marketed programs and professionals with the technological knowledge for programming applications using free integrated computational tools. This paper presents procedures for programming a map server for providing digital cartographic databases on the World Wide Web (Internet) in an interactive and dynamic, using only free software (free and / or open source). Routines are presented for programming map servers on Windows and Linux, allowing the integration of spatial information from different multidisciplinary geographical sources and presenting various digital formats. The development is part of the Research Project CAG-APQ-00387-10: "Environmental Indicators and Socio-Economic of Maize Productivity" funded FAPEMIG, attended by professionals from Embrapa / CNPMS, UFSJ / CSL, UMFG / CEDEPLAR and IBGE. The map servers can integrate both dynamic geographic information represented by thematic maps (derived from models and simplified land surface), as satellite images, orthorectified aerial photographs and 3D models or virtual reality georeferenced. The availability of information through a map server allows encompass a diverse audience. The viewing and consultation with georeferenced information can assist in making decisions based on integrated analysis of multidisciplinary information covering various knowledge areas as agricultural sciences, education and climatology.Pages: 4330-433
Assessment of the METRIC model in the estimation of instantaneous values of sensible and latent heat fluxes over a drip-irrigated Merlot vineyard using Landsat images
No full textThe performance of the METRIC (Mapping EvapoTranspiration at high Resolution with Internalized Calibration) model was evaluated to estimate instantaneous sensible (Hi) and latent heat fluxes (LEi) over an experimental plot of a drip-irrigated Merlot vineyard (Vitis vinifera L.) of 4.25 ha (35°25 LS; 71°32 LW; 125 m.a.s.l). This study was carried out using data obtained between the years 2006 and 2009. Ground data of sensible and latent heat fluxes were measured by an Eddy Covariance (EC) system. METRIC estimations of Hi and LEi considered fifteen days where Landsat scenes were available. The pixel by pixel METRIC estimations were averaged using the pixels inside the experimental plot. Measured and estimated instantaneous values of Hi and LEi were analyzed using the coefficient of determination (R2) and the mean absolute error (MAE). Results indicate that METRIC overestimated Hi by 10% (MAE = 39 W m-2) while LEi was overestimated by 14% (MAE = 33 W m-2). Results of this study indicated that the self-calibration of METRIC in Hi allowed obtain acceptable values of LEi.Pages: 490-49
Improving Utility of Low-Resolution Data using Statistical Approaches in Remote Sensing
No full textWith the increase in the multi-resolution data available from the various satellite sensors, there is an increasing need to come up with analysis techniques to handle and exploit the information that can be extracted from lower resolution (LR) data before acquiring higher resolution (HR) data. This paper presents a methodology to use statistical approaches to sub-group the LR classified data into high importance local regions (HILRs) and low importance local regions (LILRs) after filtering, for every class. The HILRs were shown to have more number of near pure-pixels as compared to the complete class regions, as verified by using the classified HR APLULC data, when a LR pixel was matched to the HR matrix using the Near Purity Measure (of 80). The HILRs were further shown to have higher stability, by showing reduced NDVI variation as compared to the complete class regions, using the HR AWIFS data. The method proposed works better for LR classes with limited intra-class heterogeneity and good inter-class separability. The proposed approach can help to reduce the processing done on HR resolution data based on the corresponding LR HILRs obtained for every class regions and further help in applications like pure-pixel matching, building HR-LR classification models and isolating pure pixels from the mixed/impure pixels in class regions.Pages: 1229-123
Geoprocessamento aplicado à avaliação e controle de inundações: o caso da bacia hidrográfica do Rio Itapemirim-ES
No full textOccurrences in flood watershed are related to their geometrical characteristics (morphometry) and physical-geographical factors, as reflected in the intensity of the flow and the water outlet. Planning guided by the occupation and mitigate the impacts of flooding can avoid disasters and losses, the example of unconventional measures by engineering works. Proceeds evaluation of watershed River Itapemirim (ES) for correlation between their measurements and the occurrences of floods, and identifying portions of the relief with the potential to create containment basins. The proposed objectives were achieved from the manipulation of vector data, altimetry and hydrographic mapping, environment in Geographic Information System (GIS) for representing the area for Hydrologically Consistent Digital Elevation Model (HCDEM). The occurrences of floods are little influenced by the geometry, which elongated format favors flow. Evaluations of hydrography and relief indicate high sinuosity channels, little infiltration in the headwaters and levels formation, which favors runoff concentration and flow downstream. Were identified 40 sections with potential for flood control, whose blade cube and water are, respectively, 39.173.417m² and 376.352.305m³.Pages: 5777-578
Zoneamento morfológico da plataforma continental rasa, nordeste do Rio Grande do Norte, Brasil
No full textContinental Shelf represents areas affected by sea level oscillations in the Quaternary period. It marks the importance of this region in the study of coastal evolution. Submerged geomorphological features can be found from shallow regions to the edge of the platform outside the Brazilian Northeast shelf. This study aimed to perform a new zoning feature of shallow submerged continental shelf, northeastern state of Rio Grande do Norte, using bathymetric data and interpretation of satellite imagery. To define the zoning of the study area, we performed an adaptation of an old zoning quoted in the literature. In this adaptation, we used the bathymetry data and visual interpretation of remote sensing products in decision making. It was also performed an Kruskal-Wallis test followed by post-hoc Dunn, to compare bathymetric data between the new featured zones. Results showed, expressively, the presence of conspicuous geomorphological features of the study area. We determined 5 zones with distinct characteristics, presenting a positive gradient in water depth from the shoreline. The main structures that stood out were the channel of San Roque, coral reefs, underwater dunes, transverse dunes and stabilized algae zone. Integrated use of different types of remote sensors, especially chemical grouping information along with physical environment information, represents a strong methodology in submerged mapping information.Pages: 3680-368
Geoprocessamento aplicado à identificação da vulnerabilidade do solo urbano da cidade de Francisco Beltrão PR
No full textThe rapid growth of urban sprawl these days has created many environmental problems from recurring high human activity in urban areas,especially in relation to intensification of erosion. Increasingly we see the need to conduct studies and create methodologies to analyze the effects of disordered occupation around shopping centers and urban. This paper presents the results of the application of GIS techniques andremote sensing as tools for evaluating the potential of land use of the urban perimeter of the city of Francisco Beltrão - PR. The methodology presented was based on Ross 1994 lets you work with three variables to determine the vulnerability of urban land use, which are: texture, soil type and slope. The results were obtained by processing data in the program SPRING 5.2, along with geological and soil analysis laboratoryand field, obtaining thematic maps of slope, soil type, land use and vulnerability. We also carried out the analysis of permanent preservation areas within the perimeter studied. The generated maps are essential tools for the analysis and identification of environmental problems in thestudy area and also serve as a basis to assist in the development of the master plan and other projects of urban growth.Pages: 5177-518
Evapotranspiration of tamarisk through micrometeorological and remote sensing techniques
No full textThe main objective of this study was to determine the daily actual evapotranspiration (ETa) of the tamarisk vegetation utilizing micrometeorological data and remote sensing algorithms. The Bowen ratio method, and the Surface Energy Balance Algorithm for Land (SEBAL) and Simplified Surface Energy Balance Index (S-SEBI) algorithms were used to obtain the ETa of the tamarisk vegetation, located in the preserved area of the Cibola (Blythe, CA/USA). In general, the estimated values of ETa by the SEBAL and S-SEBI algorithms present results close to the measured values in the flux towers. The RMSE between the measured values and the estimated values by SEBAL was 0.4 mmday-1, and for the measured values and the estimated values by S-SEBI was 0.5 mmday-1, resulting in a percentual mean error of 9.5% between the measurements and the SEBAL and 10.6% between the measurements and the S-SEBI, evidencing the applicability of both the algorithms in obtain the daily actual evapotranspiration.Pages: 6260-626