Seed bank of Caatinga soil submitted to sustainable forest management plan in Cuité-PB

Abstract

The objective of this work was to evaluate the soil seed bank in a managed caatinga area, under different cutting ages: Legal Reserve, UPA 2007, UPA 2012 and UPA 2014, located in the Agrarian Reform Settlement, Brandão III, Cuité-PB. Ten samples of litter (soil + soil) from each area were collected inside an area of 25m2 in the lower right corner, using an iron template of 30 cm x 50 cm x 3 cm. The material was packed in plastic trays with 20 cm x 14 cm x 5 cm and taken to the Forest Nursery of the UFCG, Campus of Patos and kept under 50% shading under daily manual irrigation during an experimental period of seven months. The species present were deposited in the UFCG herbarium. For floristic diversity, the diversity index of Shannon-Weaver (H '), equability by the Pielou Index (J') and Sorensen (SO) similarity were estimated. Seedling density and richness were compared by the Tukey test at 5%. In the 40 trays from the four experimental units emerged 1,993 individuals belonging to 22 botanical families and 49 species. The Shannon-Weaver index (H '), found for the four experimental units were: 2.33 nats. ind-1, 0.99 nats.ind-1, 2.19 nats.ind-1 and 1.35 nats.ind-1 for Legal Reserve, UPA 2007, UPA 2012 and UPA 2014. The seed bank in the three areas of managed caatinga are composed predominantly by herbaceous species. The areas were similar in respect to the index of similarity.