Phosphate fixation in soils from the state of Rio de Janeiro

• Autor(a) principal: Almeida, Dejair Lopes de
• Data de Publicação: 2014
• Outros Autores: Velloso, Ary Carlos X.
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Pesquisa Agropecuária Brasileira (Online)
• Texto Completo: https://seer.sct.embrapa.br/index.php/pab/article/view/15981
• topic: retention capacity; Yellow Red Latosols, "tabuleiro" soils; capacidade de retenção; Latossolos Vermelho-Amarelos; solos de tabuleiro

The fixation of phosphate was studied using samples of forty soils from the state of Rio de Janeiro. The soils were equilibrated with solution of KH2PO4 10-3 M, and the fixed phosphate were determined by the difference between the initial and final concentration of solution. The phosphate fixation varied from 0.05 to 1.89 mmols/100 g of soil. These limits corresponded to 1 to 37,8% of the applied phosphate, respectively, with averages of 23.5% for the Red-Yellow Latosols, 21.5% for the Hydromorphics and Alluvials, 16.3% for the Red-Yellow Podzolics and 4.7% for the soils derived from the sediments of the terciary ("Tabuleiro" soils). The phosphate fixation values, in percentage, were closely correlated with the amounts of clay, moisture, organic matter, oxy-hydroxyds of aluminum and pH in KCI.