The variability of leaf nutrient concentrations (nitrogen, phosphorus, potassium, calcium, magnesium, zinc, copper, manganese, and iron) was assessed in a twelve-year-old orange orchard, cv. Pêra, grown on a dystrophic Yellow Latosol of medium texture plain relief, in Governador Mangabeira, State of Bahia, Brazil, 1990. A transect consisting of 50 trees, spaced four meters apart, was sampled. Twenty leaves were collected from each tree. The leaves were taken from four different points of the crown, opposite two by two, and from branches bearing fruits. Results showed that nitrogen, magnesium, zinc, and copper followed normal distribution, while phosphorus, potassium, calcium, manganese, and iron followed log-normal distribution. The highest coefficients of variation were found for K and Cu, and the lowest was for N. With the exception of P and Cu, which showed random distribution, the other nutrients exhibited spatial dependence, which ranged from 20 m (Mg) to 50 m (Ca). Positive cross-correlation was detected between soil organic matter and leaf nitrogen.
frequency distribution; coefficient of variation; geostatistics; semivariogram; spatial dependence; cross-semivariogram; foliar analysis; leaf samples