info:eu-repo/semantics/article
PHOSPHORUS ADSORPTION IN SOILS OF TROPICAL REGIONS
ADSORÇÃO DE FÓSFORO EM SOLOS DE REGIÕES TROPICAIS
Autor
Vinha, Ana Paula Carrara
Carrara, Bruna Helena
Souza, Emanuella Farias Santos
Santos, Jussane Antunes Fogaça dos
Arantes, Sayonara Andrade C.Moreno
Institución
Resumen
Phosphorus (P) is the most limiting nutrient for cultivation in tropical soils, as they generally have high phosphorus adsorption capacity. Some chemical and physical attributes of soil such as clay content, pH, effective cation exchange capacity (ECEC) and organic matter influence the adsorption dynamics. The objective of this study was to evaluate the behaviour of the phosphorus adsorption process in a Red-Yellow Oxisol and a Typic Quartzipisamment from the Cerrado-Amazon transition region, and to evaluate the soil attributes that influence the adsorption dynamics of the soil of the phosphorus. Chemical and physical characterization and Langmuir isotherm construction were performed by the “Bach” method. From the Langmuir linearized equation, the maximum P adsorption capacity (MPAC), the constant with the binding energy (KB) and the maximum capacity factor (PCFmax) were selected. There was a difference in MPAC, KB and PCFmax of the studied soils, and the highest values were found in the Red-Yellow Oxisol, mainly due to the higher clay content in relation to theTypic Quartzipisamment. Organic matter was one of the few attributes that had a negative correlation with the adsorption attributes, highlighting (emphasizing) it’s importance in (soil) management to increase the efficiency of phosphate fertilization. O fósforo (P) é o nutriente mais limitante ao cultivo nos solos tropicais, que, geralmente, apresentam alta capacidade de adsorção de P. Alguns atributos químicos e físicos do solo como o teor de argila, pH, CTC efetiva e matéria orgânica influenciam na dinâmica de adsorção. O objetivo deste estudo foi avaliar o processo de adsorção do fósforo em um Latossolo Vermelho Amarelo (LVA) e um Neossolo Quartzarênico (RQ) da região de transição Cerrado-Amazônia, e avaliar os atributos dos solos que influenciam na dinâmica de adsorção do P. Os ensaios de sorção foram realizados pelo método “Batch” ou em batelada e à partir dos dados obtidos foram construídas curvas obtendo a equação linearizada de Langmuir, com as quais foram determinados os valores de capacidade máxima de adsorção de P (CMAP), a constante relacionada com a energia de ligação (KL) e o fator capacidade de P máximo (FCPmáx). Houve diferença na CMAP, KL e FCPmáx dos solos estudados, sendo que os maiores valores foram encontrados no LVA, devido principalmente ao maior teor de argila em relação ao RQ. A matéria orgânica foi um dos poucos atributos que tiveram correlação negativa com os atributos de adsorção, ressaltando sua importância no manejo para aumentar a eficiência da adubação fosfatada.
Palavras-chave: Latossolo Vermelho Amarelo; Neossolo Quartzarênico; Isotermas de adsorção.
Phosphorus adsorption in soils of tropical regions
ABSTRACT: Phosphorus (P) is the most limiting nutrient for cultivation in tropical soils, as they generally have high P adsorption capacity. Some chemical and physical attributes of soil such as clay content, pH, effective cation exchange capacity (ECEC) and organic matter influence the adsorption dynamics. The objective of this study was to evaluate the behaviour of the phosphorus adsorption process in a Red-Yellow Latosol and a Quartzarenic Neosol from the Cerrado-Amazon transition region, and to evaluate the soil attributes that influence the adsorption dynamics of the soil of the phosphorus. Sorption tests were performed using the “Bach” method, from the Langmuir linearized equation, the maximum P adsorption capacity (MPAC), the constant with the binding energy (KB) and the maximum capacity factor (PCFmax) were selected. There was a difference in MPAC, KB and PCFmax of the studied soils, and the highest values were found in the Red-Yellow Oxisol, mainly due to the higher clay content in relation to theTypic Quartzipisamment. Organic matter was one of the few attributes that had a negative correlation with the adsorption attributes, highlighting (emphasizing) it’s importance in (soil) management to increase the efficiency of phosphate fertilization.
Keywords: Red-Yellow Latosol; Quartzarenic Neosol; adsorption isotherms.