EL MANEJO DEL SUELO MODIFICA A SUS ACIDOS HUMICOS Y LA DISPONIBILIDAD DE METALES PESADOS/The soil management modifies their humic acids and the availability of heavy metals

• Published in: Cultivos tropicales 2018-04, Vol.39 (2), p.15
• Main Authors: Rodríguez, Reinaldo Reyes, Izquierdo, Fernando Guridi, Carmenate, Ramiro Valdés
• Format: Article
• Language: Spanish
• ISSN: 0258-5936

The agronomic management not efficient and with not very sustainable conditions induces unfavorable effects in the agro ecosystem, constituting source of entrance of pollutants and modifications of soil properties. In Cuba this information is not modernized, representing a danger for the agricultural production and the alimentary security. The objective of this work was to evaluate the effect of the management practices on properties of the acids humic and the availability of heavy metals two different management of a Nitisol soil of Mayabeque province, one with low antropic activity (natural grasses) and another of high antropic activity, dedicated to several cultivations. In the extracted humic acids they were evaluated optic coefficient E4/E6, threshold of clotting, the carboxylic, fenolic acidity and total acidity. It was also evaluated the pseudototal content of cations of metals heavy availability. The results demonstrated the effect of the management system, evidencing differences in the evaluated properties. The hydrophobicity, the level of structural condensation, the quantity of carboxylic groups and the total acidity of the humic acids diminished as consequence of the intensive cultivation, what could imply that they are affected the functions that the humic acids should exercise in the soil plant system. In that management they also registered affectations in the remaining evaluated properties, registering the biggest values for [Cu.sup.2+], [Ni.sup.2+], [Pb.sup.2+] and [Zn.sup.2+], as well as that was a superior content to the one referred as permissible maximum in several countries in the case of the [Cd.sup.2+] and for the Nitisol soils of Cuba. Key words: contamination, agricultural practical, humic substances El manejo agronómico no eficiente y con condiciones poco sustentables, induce efectos desfavorables en los agroecosistemas, constituyendo fuente de entrada de contaminantes y modificaciones de las propiedades del suelo. En Cuba no está actualizada esta información, lo que representa un peligro para la producción agrícola y la seguridad alimentaria. El objetivo de este trabajo fue evaluar el efecto de las prácticas de manejo sobre propiedades de los ácidos húmicos y la disponibilidad de metales pesados en dos manejos diferentes sobre un suelo Ferralítico Rojo de la provincia Mayabeque; uno con baja actividad antrópica (pastizal) y otro de alta actividad antrópica, dedicado a cultivos varios. En los ácidos húmicos extraídos se evaluaron