Eliana Lima da Fonseca

Estimativa da disponibilidade de forragem do bioma Campos Sulinos a partir de dados radiométricos orbitais: parametrização do submodelo espectral

This research presents the parameterization for the spectral submodel of JONG model, an agrometeorologic-spectral model to forecast the available forage of natural pastures of Campos Sulinos biome. Tthe capacity of different spectral variables, gotten from images of the sensor ETM+/Landsat 7, to represent the forage availability in different phases of its fenologic cycle was realized. The Wetness variable and reflectance of the band ETM+7/Landsat 7 represent the initial status of vegetation of efficient form was verified, however had no sensitivity enough to eliminate the effect of soil type in the spectral response of the vegetation.

Multiscale Trend Analysis for Pampa Grasslands Using Ground Data and Vegetation Sensor Imagery

This study aimed to evaluate changes in the aboveground net primary productivity (ANPP) of grasslands in the Pampa biome by using experimental plots and changes in the spectral responses of similar vegetation communities obtained by remote sensing and to compare both datasets with meteorological variations to validate the transition scales of the datasets. Two different geographic scales were considered in this study. At the local scale, an analysis of the climate and its direct influences on grassland ANPP was performed using data from a long-term experiment. At the regional scale, the influences of climate on the grassland reflectance patterns were determined using vegetation sensor imagery data. Overall, the monthly variations of vegetation canopy growth analysed using environmental changes (air temperature, total rainfall and total evapotranspiration) were similar. The results from the ANPP data and the NDVI data showed the that variations in grassland growth were similar and independent of the analysis scale, which indicated that local data and the relationships of local data with climate can be considered at the regional scale in the Pampa biome by using remote sensing.

Caracterização espectral multitemporal dos cereais de estação fria em imagens de satélite com média resolução espacial

In order to evaluate the satellite image patterns between such cool season cereals cultivated areas intended for grazing or grain pro ductio n, No rmalized Differe nce

Contribuições do solo e dossel em modelo de estimativa de biomassa aérea no Bioma Pampa

The objective of this work was to evaluate the predictive performance of the JONG models spectral submodel, with the insertion of variables considering contributions of different underlying soils and canopy densities. Indices calculated by subtraction and simple ratio between 4 and 3, 4 and 5, 4 and 7 bands, of Landsat 7/ETM+ sensor - were suggested in order to represent the spectral contribution of the different underlying soils and the influence of canopy structural differences. The spectral component parameterization was implemented by multiple linear regression and, then, it was compared to the biomass data measured in the field. Spectral variables that better describe the variations of initial biomass availability and soil spectral contributions were the soil fraction (spectral mixture linear model), and ratio between 4 and 7 bands. The spectral component of the JONG model, with the new parameterization, showed sensibility in eliminating the canopy and soil influences in the biomass initial availability and, also, improved the interpretation of results due to the relationship between selected spectral variables.

Spatio-temporal analysis of Lençóis Maranhenses between 1984 and 2014 using orbital remote sensing

monitoring of its dynamics. The objective of this study were to analyze the spatio-temporal dynamics of the Parque Nacional dos Lençóis Maranhenses, mapping the changes in the dunes system using satellite imagery, from 1984 to 2014. For this analysis were used satellite images acquired by TM-Landsat 5 and OLI-Landsat 8 sensors. The park boundary, in the inner part of the continent, was vectored for the initial and final year of analysis, generating maps with the changes in the dunes locations in the 31 years period identified the forward areas and retraction and areas. The total area of advancement of dunes was 23.69 km2 while the downturn area was 14.95 km2. It was identified expansion of coastal dunes toward the interior of the continent towards northeast southwest, following the movement of trade winds. Were selected four points of observations which were monitored changes in land cover from the annual change of the surface reflectance values in the near infrared band, allowing identify both the type of change and its time of occurrence.