Utility of woody vegetation in a Caatinga area in the state of Pernambuco, northeastern Brazil

摘要

This study had as its objective the analysis of the relationship between the human population located in the settlement of the Olho d′água do Félix, Caruaru (Pernambuco state) and the forest species known and used, in order to test the hypothesis of ecological appearance. It was conducted an inventory of the arboreal vegetation through the sample plot of 400 m2 in the existing forest fragments in the settlement. The data obtained were used to calculate density, dominance, frequency, importance value. These results were compared with the Ethnobotanical data in order to test the hypothesis that the availability of a resource (appearance) is related to its importance for the population (determined by the value in use). Twenty-five key informants were interviewed and identified the native tree species and their uses. These ones were presented to the interviewer through a guided tour. Twenty-seven species have been cited and classified into nine categories: food, animal feed, fuel, construction, technology, medical, veterinary, environmental services and other uses. Quotations for non-timber uses of the vegetation concentrate the largest number of species, a value that was influenced by the categories animal feed and human food. It was indicated the use of the following plant parts: bast, flower, leaf, fruit, latex, wood, whole plant, root and seed. The use of wood had 74.8% of the quotes. Families with greater value in use were Rhamnaceae and Anacardiaceae, households with the largest number of species were Fabaceae (9 spp.) and Euphorbiaceae (5 spp.). The species with the highest value of importance were Croton blanchetianus Baill., Acacia farnesiana (l.) Willd. and Commiphora leptophloeos . The species of greatest value in use were Mimosa tenuiflora . Benth, Ziziphus Jacobus Mart Croton blanchetianus Baill. The categories fuel, construction and medical were the most abundant ones. It was verified that the species with less number of parts of the plant used had lower value of use, and those with greater number of parts were more likely to have a greater number of uses. It was noticed that the combined index (VU x VI) has a positive correlation with relative density, relative frequency, importance value and relative dominance. The correlation in the order of species between the value of use and relative frequency (r = 0.3260, p 0.01) was significant, and between the value of use and the relative dominance (r = 0.3987, p 0, 05). The species with the lowest number of parts used had lower value of use, and those with greater number of parts had a greater chance of having a greater number of uses. The amount of uses, used parts and wealth, demonstrates the caatinga utilitarian potential for the communities, and that this traditional ecological knowledge can be used to prospect new products and uses for wood and non-wood products.