Crescimento inicial de espécies florestais de diferentes grupos sucessionais em resposta a doses de fósforo

Abstract

With the aim of evaluating the responses of forest species to phosphorus supply, an assay under greenhouse conditions was carried out, where seedlings of pioneer tree species (Lithraea molleoides, Schinus terebinthifolius, Piptadenia gonoacantha, Mimosa caesalpiniaefolia, Sesbania virgata), a light-demander climax species (Hymenaea courbaril), and the shade-tolerant climaxes species (Calophyllum brasiliensis, Tabebuia serratifolia, Myroxylon peruiferum) were cultivated. Five phosphorus doses were used, corresponding to 0, 100, 250, 500 and 800 mg dm-3 of P. Stem diameter, height, and root, shoot and total dry matter yield of the plants were evaluated. The pioneers species were more responsive to phosphorus furnishing, indicating the need of phosphorus supply for the adequate development of these species. The climaxes species showed to have low sensitivity to phosphorus supply, reflecting a lower requirement in the initial growth period. The differences in relation to growth rate and seed size may be connected to the contrasting behavior observed for pioneers and climaxes species.