P forms in Oxisol soil under pasture after two and seven years of phosphate fertilization
DOI:
https://doi.org/10.19084/rca.19451Abstract
In more weathered soils such as Oxisols, the use of phosphate fertilizers can ensure higher availability of phosphorus to plants. This study aimed to evaluate the forms of phosphorus in the Oxisol soil under pasture after two and seven
years of applying simple superphosphate doses. The treatments consisted of five doses of simple superphosphate, applied and maintained on the surface of the Brachiaria brizantha cv. Marandu in 2010. Soil samples were collected in the 0-10 and 10-20 cm layers after two (2012) and seven years (2017) of phosphate fertilization, and submitted to chemical fractionation to determine phosphorus forms in the soil. After two years of phosphate fertilization, there was an effect of doses on phosphorus levels in organic, inorganic forms and labile, moderately labile and no-labile fractions, with an increase in their contents as a function of phosphorus doses, being more expressive in layer 0 -10 cm from the ground. Seven years later, there is a predominance of phosphorus in no-labile fraction, being the phosphorus contents in organic
and inorganic form and the labile and moderately labile phosphorus fractions were not influenced by fertilization.