Fenologia de espécies florestais da caatinga em ambientes com diferentes estádios de conservação.

Abstract

Phenology of forest species of the caatinga in environments with different stages of conservation. The Caatinga occupies the equivalent of 11% of the national territory, with an area of approximately 844,453 km², between the coordinates 2º 54 'to 17º 21' S, contains rare and endemic species important for the Brazilian biodiversity, but it has undergone anthropic interventions and degradations for long periods. Phenology is the study of the behavior of plants and reproductive and vegetative cycles and their relationships with the environment. Thus, the objective of this study was to characterize the phenological behavior of four native species present in two caatinga fragments: antopic (Nupeárido Farm) and an advanced recovery process (Tamanduá Farm), in addition to seeking to answer the following questions: species of the Caatinga present differentiated phenological patterns as a function of the level of anthropic alteration? When do reproductive and vegetative phenomena occur in both areas? Is there synchrony of flowering and fruiting between the areas and species and within the species studied, in each area? Are there positive correlations between phenological events and environmental factors? For the phenological monitoring, monthly visits were made to 10 individuals of the species: Commiphora leptophloeos, Aspidosperma pyrifolium, Poincianella pyramidalis and Mimosa tenuiflora, in both areas. The activities and intensities of the phenophases were evaluated: flowering, fructification, leaf flushing and leaf fall from December 2014 to December 2015, and the data obtained were correlated with temperature and monthly precipitation of the areas through Spearman correlation. The species P. pyramidalis and M. tenuiflora presented different phenological patterns in each area. The maximum leaf flushing peaks occurred during the rainy season and leaf fall during the dry period, in both areas. There was synchronization of flowering and fruiting within the studied species and between C. leptophloeos and A. pyrifolium, in both areas. There was a positive correlation between flowering and temperature for C. leptophloeos in both areas, and between flowering and precipitation at Tamanduá Farm for P. pyramidalis. All species showed a positively related leaf flushing with precipitation in both areas. The hypothesis tested was partially proven.