Estudo da regeneração natural de espécies arbóreas em quatro fragmentos de Floresta Ombrófila Densa no município de Catende, zona da mata sul de Pernambuco

Abstract

The study was developed in the fragments calls Mata das Galinhas, Mata Santa Luzia, Mata Conceição and Mata das Caldeiras, situated in the Catende’s-PE city (8o40'00 "S and 35o35'00" W), in mesoregion of the pernambucana forest, more necessarily in the humid forest’s microregion, at 142 km of the capital. The area’s vegetacion is Humid Forest. The relief varies wavy to very wavy, with 199 m altitude. The city is allowed at river Una’ watershed. The predominant soil is classified as red latisols dystrophic and red nitosols associated to latisols. The present work aims to study and evaluated the total natural regeneration of arboreal species in the forests fragments and to verify the similarity, diversity and structure of the species in the same ones. . For estimate the natural regeneration, were made systematically 40 subunits (samples with 5 x 5 m), where in 10 subunits in each fragment. These subunits were inserted in the middle samples (10 x 25 m) before used to evaluate the community arboreal phytossociology, with 50 meters between the ones. The regeneration study (CAP < 15 cm) was developed with heights divided in three categories (1 – individuals with minimum heights 1 < 2 m; 2 - individuals with minimum heights 2 < 3 m; 3 - individuals with heights > 3 m). Besides, the samply sufficient, similarity and diversity were calculated. For the fragments, 34 botanical families and 71 arboreal species inside 492 individuals. 64 had been identified in level of species, 4 in sort level, 1 in family level and 2 are not identify. Ten species obtained bigest values for total natural regeneration (RNT) and contribute with 52,5% of the total percentage, how is descript following way: Eschweilera ovata (Camb.) Miers. (7,6%), Brosimum discolor Schott. (6,8%), Protium heptaphyllum (Aubl.) Marchand (6,5%), Thyrsodium spruceanum Benth. (6,3%), Cupania racemosa (Vell.) Radlk. (5,7%), Helicostylis tomentosa (Poepp. & Endl.) Rusby (5,5%), Rheedia gardneriana Planch. & Triana (4,6%), Cupania revoluta Rolfe (3,6%), Nectandra cuspidata Nees & Mart. (3,5%) and Siparuna guianensis Aubl. (2,4%). These species had presented a good capacity of regeneration, probably they will be main responsible for the maintenance of forest’s structure and physiognomy. The diversity (H ') was 3,65 nats/ind to all fragments. However, Mata das Galinhas fragment got a bigger value to diversity (3.44 nats/ind) than the others ones. The similarity’s analysis, in the Euclidean distance got a bigger value between the Mata das Galinhas and Conceição fragments than the others ones, nevertheless they demonstrated a bigest different between the same ones and Mata das Caldeiras fragment.