ABSTRACT
Floristic and structural patterns related to anthropic degradation of the caatinga were identified based on the selection of plant communities in three situations: degraded, moderately degraded, and non-degraded. Plants were sampled from three vertical strata: upper woody (height ≥ 3 m), lower woody (50 cm ≤ height < 3 m), and regeneration (height < 50 cm). Richness, density, and diversity were estimated, and speciesdensity and species-area curves were analyzed. A decrease in the number of species was one of the effects of degradation: among the stratum of the lower woody plants, the number was three in the degraded area and 10 in the non-degraded area. Diversity and density were also lower in the degraded area (0.56 and 2,328 ind/ha) compared to the non-degraded area (1.32 and 26,557 ind/ha). Malvastrum coromandellianum dominated the lower woody stratum in the degraded area, while Cordia leucocephala and Croton mucronifolius were dominant in non-degraded area. Influence from degradation was not detected in the regeneration stratum, except for the smaller number of species in the degraded environment that was estimated by the species-area model.
Key words:
desertification; species diversity; species-area curve; vertical strata; Northeast