Fertilidade do solo e estado nutricional de pau-rosa em função do ciclo de cultivo e densidades populacionais

Abstract

A little is known about the nutritional requirement of rosewood (pau-rosa) trees, especially during the crop cycle and in different densities. This study aimed to verify soil fertility and nutritional status in pau-rosa homogeneous plantations in Central Amazon region, Brasil depending on the crop cycle and population density. The study was made in eight plantations at different ages 6; 7; 11; 12; 16 and 19 years old, with population densities ranging from 833 to 2500 plants per hectare, located in the Maués-AM district, estate of Amazon. Each tree stand was divided into plots, each plot was formed by four pau-rosa plants. In each plot soil and leaf samples were collected in the middle region of the plant, to be chemically characterized. Most soils plantations at high pH, the saturation of very low basis deficient as to the elements P, K, Mg, Mn, Zn and B and with excess Al3+, Cu and Fe primarily in layers 0-5 and 5 -10 cm. Furthermore, Ca are low while Al3+ values are elevated in 20-30 cm deep layer. The plants became deficient in N, P, K, Ca, S, Mn, Zn, B. The results showed that age of crops affected the nutritional status of rosewood plantations, while it was not observed influences on tree densities plantations. Therefore, there is need for adjustments to the correction and fertilization programs in rosewood plantations of central Amazon region.