Nutrition of tree species in tropical dry forest and rainforest environments

ABSTRACT Knowledge of the nutritional efficiency of species can help revegetation of forest areas, guiding the use of species that best adapt to environmental humidity, altitude and diversity. The objective of this study was to evaluate the nutrient utilization efficiency of N, P, K, Ca and Mg of dominant species in tropical dry forest and rainforest environments. The work was carried out in two areas, both in Pernambuco state, characterized as: Tropical Dry Forest of Caatinga and Tropical Rainforest of Atlantic Forest. A floristic and phytosociological survey was carried out. Species with highest density were evaluated, four from the dry forest and three from the rainforest. For each species, leaves of five healthy individuals of similar size were sampled and nutrient contents were determined. Leaf biomass was estimated by allometric equations. Rainforest species were more efficient in the use of N and K, and dry forest species in the use of P and K. In the dry forest environment, the species Pilocarpus spicatus and Guapira oposita stored more nutrients, and in the rainforest, the species Dialuim guianese was more efficient. These species are essential for the balance of ecosystems and the continuous and sustainable cycling of nutrients.