Understanding spatial patterns of land use and land cover is essential for studies addressing biodiversity, climate change and environmental modeling as well as for the design and monitoring of land use policies. The aim of this study was to create a detailed map of land use land cover of the deforested areas of the Brazilian Legal Amazon up to 2008. Deforestation data from and uses were mapped with Landsat-5/TM images analysed with techniques, such as linear spectral mixture model, threshold slicing and visual interpretation, aided by temporal information extracted from NDVI MODIS time series. The result is a high spatial resolution of land use and land cover map of the entire Brazilian Legal Amazon for the year 2008 and corresponding calculation of area occupied by different land use classes. The results showed that the four classes of Pasture covered 62% of the deforested areas of the Brazilian Legal Amazon, followed by Secondary Vegetation with 21%. The area occupied by Annual Agriculture covered less than 5% of deforested areas; the remaining areas were distributed among six other land use classes. The maps generated from this project -called TerraClass -are available at INPE's web site (http://www. inpe.br/cra/projetos_pesquisas/terraclass2008.php). KEYWORDS: Remote Sensing, Tropical Deforestation, TerraClass, Image Processing.Mapeamento do uso e cobertura da terra na Amazônia Legal Brasileira com alta resolução espacial utilizando dados Landsat-5/TM e MODIS RESUMOEntender o padrão espacial do uso e cobertura da terra é essencial para estudos de biodiversidade, mudanças climáticas e modelagem ambiental, bem como para concepção e acompanhamento de políticas direcionadas ao uso da terra. O objetivo deste estudo foi criar um mapa detalhado do uso e cobertura da terra para a porção desflorestada da Amazônia Legal Brasileira, até 2008. Dados de desflorestamento e uso foram mapeados usando imagens Landsat-5/TM analisadas com técnicas como modelo linear de mistura espectral, fatiamento e interpretação visual, auxiliados por informações temporais de NDVI extraídas de série temporal de dados MODIS. O resultado deste estudo é um mapa de uso e cobertura da terra com alta resolução espacial para toda Amazônia Legal Brasileira, para o ano de 2008, e os respectivos percentuais da área ocupada por diferentes classes de uso da terra. O resultado mostrou que, quatro classes de pastagens cobrem 62% da área desflorestada da Amazônia Legal Brasileira, seguida pela vegetação secundária com 21%. A área ocupada pela agricultura anual cobriu menos de 5% das áreas desflorestadas; as áreas restantes estavam distribuídas em outras seis classes de uso da terra. Os mapas gerados por este projeto, chamado TerraClass, estão disponíveis no site do INPE (http://www.inpe.br/cra/projetos_pesquisas/terraclass2008.php). PALAVRAS-CHAVE: Sensoriamento Remoto, Desflorestamento Tropical, TerraClass, Processamento de Imagens.
We present a generic spatially explicit modeling framework to estimate carbon emissions from deforestation (INPE-EM). The framework incorporates the temporal dynamics related to the deforestation process and accounts for the biophysical and socioeconomic heterogeneity of the region under study. . We conclude that the INPE-EM is a powerful tool for representing deforestation-driven carbon emissions. Biomass estimates are still the largest source of uncertainty in the effective use of this type of model for informing mechanisms such as REDD+. The results also indicate that efforts to reduce emissions should focus not only on controlling primary forest deforestation but also on creating incentives for the restoration of secondary forests.
Abstract:In response to the need for generic remote sensing tools to support large-scale agricultural monitoring, we present a new approach for regional-scale mapping of agricultural land-use systems (ALUS) based on object-based Normalized Difference Vegetation Index (NDVI) time series analysis. The approach consists of two main steps. First, to obtain relatively homogeneous land units in terms of phenological patterns, a principal component analysis (PCA) is applied to an annual MODIS NDVI time series, and an automatic segmentation is performed on the resulting high-order principal component images. Second, the resulting land units are classified into the crop agriculture domain or the livestock domain based on their land-cover characteristics. The crop agriculture domain land units are further classified into different cropping systems based on the correspondence of their NDVI temporal profiles with the phenological patterns associated with the cropping systems of the study area. A map of the main ALUS of the Brazilian state of Tocantins was produced for the 2013-2014 growing season with the new approach, and a significant coherence was observed between the spatial distribution of the cropping systems in the final ALUS map and in a reference map extracted from the official agricultural statistics of the Brazilian Institute of Geography and Statistics (IBGE). This study shows the potential of remote sensing techniques to provide valuable baseline spatial information for supporting agricultural monitoring and for large-scale land-use systems analysis.
22 23 Brazil contains two-thirds of remaining Amazonian rainforests and is responsible for the 24 majority of Amazon forest loss. Primary forest loss in the Brazilian Amazon has declined considerably since 2004, but secondary forest loss has never been quantified. We use a recently-developed high-resolution land use/land cover dataset to track secondary forests 27 in the Brazilian Amazon over 14 years, providing the first estimates of secondary forest 28 loss for the region. We find that secondary forest loss increased by (187 48) % from 29 2008 to 2014. Moreover, the proportion of total forest loss accounted for by secondary 30 forests rose from (37 3) % in 2000 to (72 5) % in 2014. The recent acceleration in 31 secondary forests loss occurred across the entire region and was not driven simply by 32 increasing secondary forest area but likely a conscious preferential shift towards clearance of a little-protected forest ecosystem (i.e. secondary forests). Our results suggest that secondary forests loss have eased deforestation pressure on primary forests. However, this has been at the expense of a lost carbon sequestration opportunity of 2.59-2.66 Pg C over our study period.
The physical phenomena derived from an analysis of remotely sensed imagery provide a clearer understanding of the spectral variations of a large number of land use and cover (LUC) classes. The creation of LUC maps have corroborated this view by enabling the scientific community to estimate the parameter heterogeneity of the Earth’s surface. Along with descriptions of features and statistics for aggregating spatio-temporal information, the government programs have disseminated thematic maps to further the implementation of effective public policies and foster sustainable development. In Brazil, PRODES and DETER have shown that they are committed to monitoring the mapping areas of large-scale deforestation systematically and by means of data quality assurance. However, these programs are so complex that they require the designing, implementation and deployment of a spatial data infrastructure based on extensive data analytics features so that users who lack a necessary understanding of standard spatial interfaces can still carry out research on them. With this in mind, the Brazilian National Institute for Space Research (INPE) has designed TerraBrasilis, a spatial data analytics infrastructure that provides interfaces that are not only found within traditional geographic information systems but also in data analytics environments with complex algorithms. To ensure it achieved its best performance, we leveraged a micro-service architecture with virtualized computer resources to enable high availability, lower size, simplicity to produce an increment, reliable to change and fault tolerance in unstable computer network scenarios. In addition, we tuned and optimized our databases both to adjust to the input format of complex algorithms and speed up the loading of the web application so that it was faster than other systems.
A vegetação secundária tem funções relevantes para os ecossistemas, tais como a fixação de carbono atmosférico, a manutenção da biodiversidade, o estabelecimento da conectividade entre remanescentes florestais, manutenção dos regime hidrológico e a recuperação da fertilidade do solo. O objetivo deste trabalho é, através de uma abordagem amostral, estimar a área ocupada por vegetação secundária na Amazônia Legal Brasileira (AML) em 2006. A amostragem se baseia em uma abordagem estratificada pelo grau de desflorestamento das cenas LANDSAT-TM que recobrem a AML. Foram selecionadas 26 cenas para o ano de 2006, distribuídas em sete estratos conforme o percentual de desflorestamento, nas quais foram mapeadas as áreas de vegetação secundária a partir de técnicas de classificação de imagens. Foi desenvolvido um modelo multivariado de regressão para estimar a área de vegetação secundária utilizando como variáveis independentes a área de desflorestamento, a área de hidrografia, a estrutura agrária, e área das unidades de conservação. A análise de regressão encontrou um R 2 ajustado de 0,84 , e coeficientes positivos para a proporção de hidrografia na imagem (2,055) e para a estrutura agrária (0,197), e coeficientes negativos para o grau de desflorestamento na imagem (-0,232) e para a proporção de Unidades de Conservação na imagem (-0,262 Estimation of secondary vegetation area in the Brazilian Legal Amazon ABSTRACTSecondary vegetation has many relevant functions to the ecosystems such as atmospheric carbon fixation , maintenance of biodiversity, establishment of connectivity among forest remnants, maintenance of hydrological regime, and restoration of soil fertility. The objective of this work is to estimate the area occupied by secondary vegetation in the Brazilian Legal Amazon (BLA) for 2006 using a sampling scheme. The sampling is based on a stratified approach according to the degree of deforestation observed in the 229 TM-Landsat scenes that cover the BLA. Thus, 26 scenes were selected for 2006 and distributed into seven strata, according to their degree of deforestation, in which secondary vegetation areas were mapped. A regression model was constructed to estimate secondary vegetation area in the remaining images using deforestation area, hydrographic area, agrarian structure , and area of conservation units, as independent variables. The regression analysis found an adjusted R 2 of 0.84 and positive coefficients for the proportion of hydrography in the image (2.055) and for the agrarian structure (0.197), while negative coefficients for the degree of deforestation in the image (-0.232) as well as for the proportion of Conservation Unity (-0.262
Deforestation is one of the major threats to natural ecosystems. This process has a substantial contribution to climate change and biodiversity reduction. Therefore, the monitoring and early detection of deforestation is an essential process for preservation. Techniques based on satellite images are among the most attractive options for this application. However, many approaches involve some human intervention or are dependent on a manually selected threshold to identify regions that suffer deforestation. Motivated by this scenario, the present work evaluates Deep Learning-based strategies for automatic deforestation detection, namely, Early Fusion (EF), Siamese Network (SN), and Convolutional Support Vector Machine (CSVM) as well as Support Vector Machine (SVM), used as the baseline. The target areas are two regions with different deforestation patterns: the Amazon and Cerrado biomes in Brazil. The experiments used two co-registered Landsat 8 images acquired at different dates. The strategies based on Deep Learning achieved the best performance in our analysis in comparison with the baseline, with SN and EF superior to CSVM and SVM. In the same way, a reduction of the salt-and-pepper effect in the generated probabilistic change maps was noticed as the number of training samples increased. Finally, the work assesses how the methods can reduce the time invested in the visual inspection of deforested areas.
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