Fitossociologia de um fragmento de floresta estacional semidecidual em Crato - CE.

Abstract

With the objective of getting to know the phytosociological structure, as well as its current state of conservation to a better understanding of successional characterization of dry forest environments, this work was performed on 14 hectares of Semideciduous forest (dry forest), located State Park Fundão Farm, Crato-CE. The survey of vegetation was carried out by the method of plots, where 35 sample units of 20.0 m x 20.0 m were plotted at random. All subjects with DAP≥ 5 cm were inventoried, and DNS and the total height were measured. 1813 individuals were recorded in the tree component, distributed in 63 species, distributed in 30 botanical families with AB = 51.95 m2.ha-1 and DA = 1.295 ind/ha. The Shannon diversity index (H ') was 3.27 nat.ind.-1 and Pielou evenness (J'), equal to 0.79, both of which are considered high. The species with the highest importance value (VI), were Combretum glaucocarpum, (33.82), Enterolobium contortisiliquum (31.00), Anadenanthera colubrina (22.63), Hymenaea stigonocarpa (19.53) and Amorimia rigid (15.33). Regarding the area of conservation status in the study we used qualitative descriptors Tans, where they pointed out that the fragment may be considered preserved. The most abundant individual in dry forest fragment was Combretum glaucocarpum, with 343 representatives present in 88.57% of plotted installments, with an average height of 7.72 m. This population presented distribution of diameters tending to standard inverted "J", characteristic of uneven-aged forests. The calculated values for the ratio ranged from Liocourt q5 =0.21, q6= 2.25, with most values between 0.36 and 0.56 and an average of 0.77, indicating a fault pattern in diameter distribution of individuals. The spatial distribution measured by Payandeh index tended to aggregation. The results showed that the studied area presents conserved with floristic richness compatible dry forest environments and the fragment is in the initial stage of succession with a tendency to recovery, if not occur significant disturbance.