PHYTOSOCIOLOGICAL CARACTERIZATION OF A DECIDUAL SEASONAL FOREST FRAGMENT RELATED TO THE ALTITUDE GRADIENT IN MACAÍBA / RN.
The delimitation of deciduous forests should done including several aspects, such as soil, relief and vegetation. In the Brazilian northeast, the Decidual Seasonal forest occurs in a contact zone between the Caatinga, the Cerrado and the Atlantic Forest, being narrow and transitional bands. In the RN there is a forest versatility between these ecosystems. The altitude variation is an important factor of changes in vegetation patterns, however not deeply studied in national and local forests. The study was carried out in an area of deciduous forest in the county of Macaíba, which was divided into 4 zones with a difference of 19 m of altitude between them, floristic and phytosociological data were collected. A total of 449 individuals distributed in 69 species, 49 genus and 36 families were inventoried. Fabaceae was the most representative family with 9 species and 135 individuals, followed by Myrtaceae (10 species and 98 individuals), Fabaceae-mimosoideae. The species Chamaecrista ensiformis (Vell.) H.S. Irwin & Barneby, Guapira laxa (Netto) Furlan and Zanthoxylum syncarpum Tul obtained the highest indexes FR 50, 45 and 50 and VI: 25.11%; 17.09% and 19.58% respectively. No species occurred along the whole gradient, occurring a constant input and output of taxa, the DCA score was 0.851 and -6.8794, the indexes of J'0.8432, (C) 0.9533 and H'3.532 ; the C2 presented the best values for all the indexes analyzed, evidencing a significant dissimilarity in the vegetation structure, these variations showed a smooth phissionomic change in the composition of this forest. The forest remnants in the RN have practically not been studied at the floristic, taxonomic and phytosociological points and these studies are fundamental for strategies of management and conservation of forest remnants.
Phytosociology; Province; Shrub and tree vegetation; Atlantic forest.
The delimitation of deciduous forests should done including several aspects, such as soil, relief and vegetation. In the Brazilian northeast, the Decidual Seasonal forest occurs in a contact zone between the Caatinga, the Cerrado and the Atlantic Forest, being narrow and transitional bands. In the RN there is a forest versatility between these ecosystems. The altitude variation is an important factor of changes in vegetation patterns, however not deeply studied in national and local forests. The study was carried out in an area of deciduous forest in the county of Macaíba, which was divided into 4 zones with a difference of 19 m of altitude between them, floristic and phytosociological data were collected. A total of 449 individuals distributed in 69 species, 49 genus and 36 families were inventoried. Fabaceae was the most representative family with 9 species and 135 individuals, followed by Myrtaceae (10 species and 98 individuals), Fabaceae-mimosoideae. The species Chamaecrista ensiformis (Vell.) H.S. Irwin & Barneby, Guapira laxa (Netto) Furlan and Zanthoxylum syncarpum Tul obtained the highest indexes FR 50, 45 and 50 and VI: 25.11%; 17.09% and 19.58% respectively. No species occurred along the whole gradient, occurring a constant input and output of taxa, the DCA score was 0.851 and -6.8794, the indexes of J'0.8432, (C) 0.9533 and H'3.532 ; the C2 presented the best values for all the indexes analyzed, evidencing a significant dissimilarity in the vegetation structure, these variations showed a smooth phissionomic change in the composition of this forest. The forest remnants in the RN have practically not been studied at the floristic, taxonomic and phytosociological points and these studies are fundamental for strategies of management and conservation of forest remnants.