COMPARAÇÃO DE MÉTODOS PARA DETERMINAÇÃO DE SUBSTÂNCIAS HÚMICAS EM FERTILIZANTES LÍQUIDOS COMERCIAIS

The beneficial effects of humic substances (HS) on crop development have been evidenced in the last decade, leading to the commercialization of HS products with fertilizing properties. Currently, three methods are frequently used for HS determination: method described in the manual of the Brazilian Ministry of Agriculture, Livestock and Supply (MAPA); method employed by the United States Humic Products Trade Association (HPTA) and method used for the determination of soil HS (“HS-Soil”). This study aimed to evaluate and compare the quantification of HS in commercial liquid fertilizers, by ...