National Institute for Space Research
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Variáveis e modelos para estimativa da produtividade do cafeeiro a partir de índices de vegetação derivados de imagens Landsat
No full textCoffee fields present a specific pattern of productivity resulting in high and low production in alternated years. Branches grown the first phenological year will produce coffee beans the second phenological year. In high-production years a plant works mostly to grain-filling to the detriment of new branches which will be responsible for production the following year. In low-production years the plant works rather to grow new branches which will produce beans the subsequent year. This feature can be related to the foliar biomass, which can be estimated through remote sensing derived vegetation indices. Several studies report this feature must be incorporated in modeling coffee yield coupled with agrometeorogical models. In this paper we derived Landsat vegetation indices related to coffee plots in order to obtain relationships to yield of the same coffee plots. Vegetation indices and biophysical variables were selected through stepwise regression in order to obtain the best regression models to estimate coffee yield. Outcomes of stepwise regression statistic showed that general models based on vegetation indices were not good to estimate coffee yield. Although coffee yield cannot be estimated exclusively from these models, they can be usefull coupled with agrometeorogical models for estimating coffee yield.Pages: 720-72
Detecção e Classificação de padrões da Degradação Florestal na Amazônia por meio de banco de dados celular
No full textForest degradation is a threat looms over Amazon forest. Detection and Recognition of Forest Degradation patterns are important to address forest state. This study presents the asset of application of a novel free system for spatial data mining, called GeoDMA, for distinguishing patterns in forest degradation in Brazilian Amazon. Types were related to progressive events of decreasing forest canopy. An analysis of land cover dynamic, from satellite image time series, is also showed. Method was based on cell database construction, landscape metrics and data mining techniques. Cell-based classification, provided by GeoDMA, proved to be useful in distinguishing forest degradation patterns. Errors were mostly caused by spatial and spectral resolution constraints of Landsat images (30m) than to the rules used to perform classification. Cell data base construction with resolution of 1km2 was suitable to represent forest degradation typologies. However, we recommend future studies to test finer resolution. Time analyses interval of three years between series data was not appropriate to represent land cover dynamics. Fast transition between forest and clear-cut requires analysis at annual-basis to better determine and detect forest degradation and their trajectories. Patterns have found to São Félix do Xingu may not be enough to represent all the patterns one can distinguish in Amazon region.Pages: 3397-340
Uso de dados de sensoriamento remoto em mapeamento digital de solos por redes neurais artificiais
No full textThe current demand for spatial information and the advance in processing of the machines has changed the course of the soil survey. The digital soil mapping arises in the context of improved the pedological surveys products through the use of GIS tools, knowledge of the genesis, morphology, and classification of soils, for selection appropriate attributes to represent reality, and produce a soil survey with accuracy and efficiency (cost x time). The approach used in digital soil mapping is based on the classical concepts of soil genesis and relations with terrain attributes. The objective was evaluating the effects of using remote sensing data in digital soil mapping of the river basin Guapi-Macacu (RJ). Were analyzed five different sets of attributes, in order to assess the contribution of three indices derived from remote sensing, in the performance of the classification by neural networks. They are: (i) all variables, (ii) all except clay minerals, (iii) all except iron oxide, (iv) all except NDVI, (v) all except the three indices. Image processing was performed with ERDAS and other attributes in ArcGIS v.10. The analyzes showed statistical differences between classifiers, highlighting the contribution of data derived from remote sensing. The criteria used in the evaluation (statistical indexes and concordance with the control points) indicate the set (iv) as the most suitable to represent the soil map of the area, although better performance of statistical indices has been obtained by the set (i).Pages: 9240-924
Regularização Ambiental com o Cadastro Ambiental Rural (CAR)
No full textThe Amazon biome contains about one third of the world's biodiversity, however all years observed that natural wealth has been destroyed by deforestation, burning, etc. In recent years the National Institute for Space Research (INPE) has pointed out that deforestation, in area, in the Amazon comes decreasing and its dynamics was modified, deforesting small areas in large quantities rather than large areas. Thus, the federal government launched some actions to decrease that problem, standing out The Action Plan for Prevention and Control of the Legal Amazon Deforestation (PPCDAM) having as main objective of reducing the rate of deforestation. This new aspect of deforestation brought the need to invest in new techniques, tools and approaches appropriate to confront forest fragmentation. This paper will present the results of elaboration of CAR utilizing high resolution images (SPOT-5), images of medium resolution (LANDSAT-5 TM), GPS and Geographic Information System. The studies were performed in three municipalities Marcelândia in the state of Mato Grosso, Dom Eliseu and Ulianópolis in the state of Pará. These were chosen for being in the list of priority municipalities to control actions and monitoring deforestation, in this way it is necessary to perform the CAR in 80% or more of the extent of their territory, so that they can be removed from this list. The municipalities of Dom Eliseu and Ulianópolis have left list and Marcelândia is too close to this objective.Pages: 5218-522
Revisão de Métodos de Simulação de Imagens de Sensores Ópticos
No full textThe image simulation is important in all applications that need to work with different resolution images in order to compare the impact of the resolution change in visual or statistical terms. An important issue about images simulation is the quality or fidelity of the models. How well represent are the simulated images? The most natural response appears to be dependent of the application. Some applications need only change the pixel size of the image. Others need reproduce adequately the average radiation levels and all variations into the scene. Thus, it is concluded that the methods are, and indeed must be adjusted for each problem . This research intends to examine the simulation techniques, indicating which techniques is more feasible to the actual resource and data availability. It is also intended, to contribute in feasibility studies of future sensors, where the practice of developing simulation processes before sensor construction is very common to perform possible errors prediction.Pages: 8114-812
Uso e cobertura do solo e análise quantitativa de mercúrio no bioma Cerrado, Estação Ecológica de Águas Emendadas, Planaltina, DF
No full textThe present work aimed to analyze mercury content in 14 species fishes Cichla temensis and six macrophytes points sample collected along the Lagoa Bonita, located in the smaller polygon of the Estação Ecológica de Águas Emedadas (ESECAE), integrant of the unit river system Mestre DArmas. The Ribeirão Mestre Darmas that is born from the flow of the Lagoa Bonita is one of the principal tributary of the Rio São Bartolomeu. The mercury quantitative determination (HgT) in fish muscle and of the vegetable tissue of macrophytes was accomplished with the portable equipment LUMEX (RA - 915+). Moreover, were elaborated maps the terrain and soil use and coverage map elevation digital model, with the utilization of specific softwares. Thus, were correlated total mercury data in these compartments with the factors of agricultural occupation in the spill of the area and the superficial flow in direction to the Lagoa Bonita. Can observe along the study that the mercury content in some fishes approached the standards allowed by the legislation. In spite to of being an unit of preservation of use permanent, the ESECAE presented Hg's significant values, pointing out itself monitoring programs importance of the environmental quality in this environment.Pages: 6977-698
Influência de componentes oticamente ativos relacionados a reservatórios em cascata - Rio Jacuí - RS
No full textThe construction of reservoirs in series in a river does not just transform the lotical environment into lentical but also provides different environmental situations on each reservoir. The works objective consists in the identification of the main optical differences in the waters surface in four reservoirs situated in the Jacuí river in Rio Grande do Sul. The variables water transparency, Total Suspended Solids (TSS), turbidity, chlorophyll a and spectral reflectance were used to represent the waters optically active components and to characterize the aquatic environments. The results lead to expressive differences among the reservoirs. The reservoirs situated upward in the river present waters with a higher concentration of solids in suspension and lower transparencies, while in the reservoirs downward there is a dominance of greenish color, related to the dominant effect of chlorophyll a. The limnological variables as much as the reflectance spectra indicate decrease of TSS and increase of chlorophyll in the direction of the water flow between the reservoirs. This scenery might be related to the precipitation of solids in suspension and increase of light availability in the water column on the reservoirs. Samples with chlorophyll a higher than 30ug.L-¹ showed features of absorption in the spectra of reflectance independently of TSS concentration.Pages: 9036-904
Avaliação de vulnerabilidade à perda de solo da bacia hidrográfica do Rio Icamaquã - RS
No full textThe management for sustainable use of natural resources implies obtaining knowledge regarding environmental constraints and potentials; this study aimed to identify the degree of vulnerability to loss of soil Icamaquã River basin, Pampa biome of Rio Grande do Sul; The methodology uses Landsat5/TM orbital images and information about the area as geomorphology, geology, podology, climate and land cover and uses to evaluate the processes of landscape change seamlessly into a geographic information system; The results organized in a database have identified a class of vulnerable and predominant stability, defined as moderately vulnerable represents 47% of the watershed and at least 72% of the area is covered by native vegetation; This information integrated into units allowed the basic query of useful information for planning activities and watershed management.Pages: 7430-743
Caracterização da vegetação e uso da terra da bacia Quitéria em 2007
No full textAn accelerated expansion of agricultural activities is occurring on Quitéria Basin, which is located in the State of Mato Grosso do Sul, covers part of two major biomes: Cerrado and Atlantic Forest and is located in the Paraná River basin. Therefore, the use of information on land use and vegetation remnants is important to identify and formulate proposals for restoration and maintenance of natural resources. Accordingly, the aim of this work is to show the types of land use and natural vegetation of the Quitéria for the year 2007, using the SIG Spring and existing maps. More than 76% of the basin is cleared and was replaced by pasture and sugarcane. The Quitéria Basin due to its proportion of deforested area does not protect the natural area minimum required by law. Given this situation, urgent measures to inhibition of deforestation and environmental debt recovery should be implemented in the basin in order to minimize environmental losses and seek sustainable development.Pages: 7109-711
Espectroscopia de reflectância aplicada à detecção de exsudações: inferências a partir de dados ASTER e verificações de campo
No full textHydrocarbon (HC) seepages interact with the stratigraphic column and promote a series of distinguishing features that can be detected via remote sensing, such as the increase of kaolinite and bleaching of ferric-iron-rich rocks and soils. Considering the importance of seepages for HC exploration, this research aims the remote detection of this phenomena in the Itapecuru Formation of the Parnaíba basin, as well as its field validation. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer sensor) data were processed for extraction of minerals of interest and spectral measurements were performed in the field and under laboratory conditions. Results were cross-referenced with soil gasometry analysis, which is used here as ground truth. The work demonstrated that both field and laboratory measurements are suitable to highlight features predicted in seepages. The relative increase of kaolinite shows a good correlation with sites rich in gaseous HCs. Therefore, it can be used as an indirect feature for remote seepage detection at the study area. Conversely, more comprehensive research is necessary to understand the relation between seepages and bleaching. Remote sensing detection of seepages in tropical areas with anthropic interference, as is the case here, is challenging and requires detailed studies strongly based on field checking, so that similar results as those accomplished in this work, can be closely reproduced.Pages: 3712-371