Antônio Felipe Couto Júnior

Classificação de padrões de savana usando assinaturas temporais NDVI do sensor MODLS no Parque Nacional Chapada dos Veadeiros

Savannas are the main vegetation type in Central Brazil, covering approximately 23% of the national territory. Locally known as Cerrado, Brazilian Savannas are formed by amosaic of different physiognomies such as grassland, shrubland and woodland that have atypical phenological cycle. ln this context, the MODIS data provide daily measurements well suited to monitor the seasonal phenology of vegetation. The present work aims to evaluate the advantages of the temporal signatures to detect Brazilian Savanna vegetation types in the Chapada dos Veadeiros National Park, Brazil. The adopted methodology may be subdivided into the following steps: (a) elaboration of the 3D cube of NDVI from temporal MODIS images, where the z profile corresponding to temporal signature, (b) noise elimination by combining Median Filter and Minimum Noise Fraction techniques, (c) endmember detection, and (d) spectral classification using Spectral Correlation Mapper method. The results demonstrate that the savanna physiognomies present typical temporal signatures. The endmembers correspond to the three major physiognomic domains: (a) Cerrado grassland, herbaceous dominated region; (b) Cerrado, mostly amixture of grasses and shrubs; and (c) Cerrado woodland, densely covered by trees. Comparison with Landsat 7/ETM+ image demonstrates the classification efficiency of the temporal series. The study concluded that the NDVI series is useful in differentiating the amount of vegetation types The methodology efficiency has been proved for regional delimitation of savanna physiognomies even considering the low spatial resolution of the 250m MODIS sensor and the high spectral mixture.

Tratamento de ruídos e caracterização de fisionomias do Cerrado utilizando séries temporais do sensor MODIS

Cerrado is formed by a mosaic of grassland, shrubland and woodland physiognomies with a typical phenological cycle. Thus, MODIS data provide daily measurements which allows to monitor the seasonal phenology of the vegetation. The objective of this work was to characterize savanna formations, forest formations and cerrado areas converted by anthropic actions, by using temporal series of MODIS NDVI and EVI after noise reduction. The adopted methodology should be divided into the following steps: (a) elaboration of the temporal cube with NDVI and EVI, in which the z profile corresponds to temporal signature, (b) noise elimination, (c) detection of temporal signature. The Minimum Noise Fraction Transformation (MNF) method was applied to reduce noise in temporal signature. The results showed that the NDVI values were higher than the EVI; and there was a relationship with the seasons of the year. The forest formations presented the highest values of NDVI and EVI, showing the lowest variations among the seasons. The converted areas of Cerrado presented the lowest values in both indices, and their values decreased in the beginning of the dry season, probably because it was the harvesting season. The study concluded that the NDVI and EVI temporal series are useful in differentiation among vegetation types.

Mapeamento da vegetação na floresta atlântica usando o classificador de árvore de decisão para integrar dados de sensoriamento remoto e modelo digital de terreno

The management and ecological monitoring of national parks and other protected areas requires a detailed description of the vegetation distribution patterns. This paper aims to produce a vegetation map for the Serra dos Orgaos National Park (PARNASO). This conservation unit is localized in Atlantic Forest within a topographic variation from sea level to 2,263 meters. The vegetation classification based on the ASTER satellite data, high-resolution aerial photographs and Digital Elevation Model (DEM). The DEM indicates vegetation structures in landscape with high spatial variability because it correlates with environmental factors, such as microclimate, moisture, soil and geomorphological processes. Decision tree classifier was used to extract information of DEM and remote sensing data. Seven classes were identified: Agropecuaria (1.29% of total Park area), Campos de Altitude (24.27%), Floresta Ombrofila Densa Alto-Montana (37.47%), Floresta Ombrofila Densa Montana (21.54%), Floresta Ombrofila Densa Sub-Montana (5.22%), Floresta Secundaria (4.13%), and no vegetation area (6.08%). The three highest physiognomies were associated with altitude higher than 1,000 m and represented 55.5% of the total area. The construction of decision trees combining the DEM and remote sensing information can improve the result on the forest tropical distribution.

Efetividade da compensação ambiental monetária no Brasil

In Brazil, monetary environmental compensation occurs in situations in which a project environmental impact cannot be avoided or mitigated, resting to the entrepreneur an obligation to support the implementation and maintenance of a Protected Area. The criteria for choosing the area to be benefited are related to spatial and functional connection with the same. This study aimed to evaluate the effectiveness of monetary environmental compensation, evaluating the spatial and functional connection in the application of the instrument resources. Under these circumstances we assessed if resources generated from environmental compensation tend to be applied in the project site, as well as, if the affected areas benefited belong to the same biome. Results indicated that monetary environmental compensation does not usually occur in the project nearby area; however, in 96% of cases it tends to occur in the same biome.

Papel do carbono no solo no funcionamento da paisagem na bacia do Alto São Bartolomeu, na região do Cerrado

The objective of this work was to evaluate the effect of soil carbon on landscape functioning of the Oxisols covering the plateaus of the Alto São Bartolomeu watershed, in the Cerrado (Brazilian savanna) region of Central Brazil. Soil organic carbon (SOC) concentration, carbon stocks, and some soil physical and chemical characteristics were determined at the 0–0.20-m depth on native and anthropogenic areas. Soils from cerrado stricto sensu patches were similar both physically and chemically, being affected by exchangeable Al3+ and by SOC concentrations, while anthropogenic matrices were affected by soil bulk density, pH, extractable P, and exchangeable Ca2+ and Mg2+. The estimate of spatial distribution of soil carbon better fitted had an adjusted R2 of 64.49% using soil C stock and 66.50% using SOC concentration from native and anthropic areas. Estimating SOC concentration from soil and landscape types, using geotechnologies to analyze vegetation indices, is a potential tool to evaluate the productivity of different agroecosystems, besides contributing to make management strategies more suitable on large scales.

The Canastra Range: On the Way to São Francisco River Spring

Canastra Range is located in Central Brazil, on the way to Sao Francisco River spring. The geomorphology shows strong structural control and is characterized by inverted relief on a synformal structure. The plateau has a smoother topography with an altitude ranges from 900 to 1,496 m a.s.l. and is supported by quartzite layers of the Canasta Group. Hydrological and soil conditions allow the development of Cerrado (Brazilian savanna) vegetation, mainly as wet grasslands (Campos Umidos) with earth mounds (murundus). This region is a natural water that divides between the Sao Francisco and Parana rivers, two of the major Brazilian watersheds. The boundaries of the Canastra Plateau are controlled by fault zones are developed as steep escarpments , where the main rivers leave the plateau over spectacular waterfalls. Among many waterfalls, the most famous is the 186 m high Casca D’Antas Falls, a symbol of Canastra Range and one of the most visited in the Brazilian territory. The region shows a variety of beautiful landscapes, with mountain ranges, hills, valleys, plateaus, and cliffs, and also shelters important plants and animals of the Cerrado biome, including endemic, rare, and threatened species.