Diagnóstico dos fragmentos de mata atlântica de Sergipe através de sensoriamento remoto

Abstract

The work characterizes morphologically the atlantic forest remnants of Sergipe. The descriptions are guided by five questions prepared before collection of data: i) how many rainforest fragments still occur in Sergipe? ii) How the rainforest remnants are distributed in Sergipe region? iii) How could the Atlantic forest fragments be characterized by size in Sergipe? iv) How to characterize the fragments with respect to the connectivity between them? v) What is the remnant Atlantic forest fragments` shape in Sergipe? The morphological analysis of the fragments were made using techniques of remote sensing; ENVI program and RGB color composition were used to discriminate targets in the images. Analysis of images were obtained from the Spot 5 satellite and were supplemented by aerial photographs. Fragments larger than 17 ha in area were considered. The delimitation of the study area was made through the interpretation of the relief obtained by the satellite images. Answering the first question, 403 mapped fragments make up together 36.000 ha. About distribution of the fragments, answering the second question, five groups were recognized and named according to the location: i) Santa Luzia do Itanhy-Estância, ii) Aracaju-São Cristóvão-Itabaiana, iii) Rosário do Catete, iv) Japaratuba, v) Pacatuba- Japoatã. Regarding the size (ha), most of the fragments is about 17 - 70 ha; the largest groups are located between Aracaju and Santa Luzia do Itanhy. Answering the forth question, the connectivity between the grous of fragments varied from 2 - 19 km; and the distance between the fragments themselves was about 1 km. Regarding the format, composition of the fifth question, it was adopted the verification for the circularity of the fragments, whose rates ranged from 0,006 - 0,31, showing that its borders differ from the edges of circularity. Relevant issues were discussed about each question in this work. About conservation, in spite of the atlantic forest fragments are disturbed, Sergipe still keep a satisfactory format and connectivity.