Análise multi-temporal da área de vegetação de manguezal da RESEX Marinha Baía do Iguape (BA)

This paper aimed to evaluate the change in mangrove cover in the navy extraction reservation (RESEX) Iguape Bay, Bahia, Brazil, in the period 1996 to 2010, once the this is an environment of great importance to ecological balance and also represents an indispensable resource for many human populations living in these places. The multitemporal analysis of the coverage of mangrove forest was performed using bands 3, 4 and 5 from two TM/LANDSAT 5 images of the years 1996 and 2010. This images had been selected under the criterion of minimum percentage of cloud coverage in the established periods and was processed by the technique of pixel segmentation. The band selected was the band 4 (near Infra Red) and for pre-classification, was calculated the Kappa and Pabak indexes, which reached, respectively, 0.85 and 0.9. Completed the classification of mangrove areas, was calculated coverage of mangrove forest for an objective comparison of changes over time. From the quantitative analysis of images, it was found that coverage of the mangrove forest showed an increase of 3 km2 in the period, growing from 26 km2 in 1996 to a total of 29 km2 in 2010, according to research data. It is important to note that the values found in this study are consistent with similar studies done in the Iguape Bay. Finally, one can infer that the Bay Iguape presents good condition for conservation of mangroves, confirming the prospect of sustainability of traditional peoples in their home environment and livelihood.Pages: 5046-505

Avaliação da delimitação subfisionomica da caatinga a partir da aplicação de análise discriminante em valores de reflectância de imagem do sensor Landsat TM 5

The objective that guided this study was to evaluate changes in spectral subformations Savannah Steppe (Caatinga) and areas of irrigated agriculture bounded by Veloso (1991) from a technical application of multivariate statistical analysis (discriminant analysis), with the objective of verifying the possibilities of separation of these categories in periods of drought. For its development we used a LANDSAT 5 TM, orbit 216, Item 066, date 20/11/2009, converted to physical values of reflectance to unify the scale of the bands. Data collection was performed by guiding the mapping PROBIO (Conservation and Sustainable Use of Biological Diversity) for choosing the sample areas. The pixels chosen were selected by the operator using the following criteria: i) the more central areas of the class ii) areas not visually degraded, or iii) areas known in the field. The results from the application of discriminant analysis showed a real differentiation between categories. On the other hand, have accused some pixels near boundaries of other categories, probably due to leaf fall pattern of the vegetation types. The bands that best discriminate the categories analyzed in this work were the first band, band 2, band 3 of Landsat 5 TM, covering the entire visible spectrum. Unexpectedly contrasting the importance of using the infrared bands for the classification of vegetation types.Pages: 4382-438

Avaliação multitemporal da dinâmica de uso e ocupação do solo nas imediações do estuário da RESEX Marinha Baía do Iguape: Realidade e Perspectivas para o gerenciamento

The diversity of tools and possibilities offered by GIS techniques and remote sensing have exerted a transformative role in the methodologies previously used by academic institutions, mainly in issues related to antropic impact studies in the land surface. From this perspective, the present study aimed to analyze the variation multitemporal the use and occupation of land nearby of the Marine Extractive Reserve Iguape Bay, Federal Conservation Unit, located between the municipalities of Cachoeira and Maragogipe in the state of Bahia, in the periods of 2000 to 2010. For this finality, were analyzed images provided by INPE through of the satellite LANSAT 5, which were processed by the technique of pixel segmentation, using the Idrisi software, version 14.0-1987/2003, followed by a supervised vectoring in the ArcGis program, version 10.1, and objective comparison of the changes caused over time from the Dynamica EGO 1.4 software. As a result, was evidenced a small increase in the anthropized areas with destination to the activities of pastures and agriculture, as well as decrease of forest environments and mangrove in the investigated unit. From the foregoing, it is highlighted that, according to the results achieved, the need for greater attention and oversight by the management bodies of this RESEX, as well as stimulating and maintaining of the sustainable practices developed by the of the traditional population of the region, in order to conserve the resources of this ecosystem of great environmental relevance.Pages: 5428-543