With the objective of assisting sampling systems and planning orange experiments, soil variability was assessed in a twelve-year-old orange orchard, cv. Pera, 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 4 m apart, was sampled. Soil samples were taken from a fixed point under the tree drip line on the successively fertilized strip. Results showed that only phosphorus and gravimetric soil moisture […]

The fumigation-extraction method was used for measuring soil microbial biomass of C (BM-C) and N (BM-N) in a red-yellow latosol under different forest types. Soil samples from eucalypt and pine plantations presented higher values of BM-C (223.72 and 207.39 mg kg-1 of C in the soil, respectively) than samples from Piptadenia rigida and regenerating secondary forest (82.94 and 79.47 mg kg-1 of C in the soil, respectively). Similar results were obtained for the litter layer. On the other hand, the […]

The application of a surface complexation model to determine the effect of the pH and the phosphate concentration in the soil solution on the adsorption of phosphorus in two acric soils, was evaluated. Surface and subsurface samples were collected from two Oxisols of Ribeirão Preto and Guaíra, northern of the State of São Paulo, Brazil, in 1993. The samples were incubated with increasing amounts of calcium carbonate and hydrochloric acid to change the pH. The adsorption curves were obtained by […]