Mobility of heavy metals as related to soil chemical and mineralogical characteristics of Brazilian soils

Abstract

In order to better understand the relationship between soil characteristics and mobility of some heavy metals, correlation studies were conducted in samples of unlimed and limed A, B and C horizons of three Brazilian soils, representative of the majority of the tropical soils. A number of chemical and mineralogical characteristics of one Oxisol and two Ultisols were related to the retardation factors (Rf) for zinc (Zn), cadmium (Cd), copper (Cu) and lead (Pb). The retardation factors, obtained in leaching column experiments, were used as an estimate of solute movement in the profile. Soil types and soil horizons were found to influence metal retardation factors which, in turn, correlated better with the chemical than the mineralogical soil characteristics. For the unlimed soil samples, the soil characteristics that significantly correlated with Zn-Rf and Cd-Rf were the sum of exchangeable bases (SB), and soil exchangeable (Ca-KCl) and non-exchangeable (Ca-HCl) calcium contents. These results showed the strong influence of the cation exchange phenomenon on the retention and mobility of these two metals. For Cu and Pb, not only SB, cation exchange capacity (CEC) and Ca-KCl and Ca-HCl but also the organic matter correlated well with the Rf, showing that complex or chelate formation may play an important role in the movement of these elements. The important soil chemical characteristics related to the retardation factors in the limed soil samples were SB for Cd, and Ca-HCl for Cu and Pb, suggesting that precipitation may also influence the mobility and retention of the latter two heavy metals in these soil samples. Soil pH influenced the heavy metals adsorption and movement as shown by the significant correlation with the retardation factors when the combined data for the unlimed and limed soil samples was considered.

Characterization of biochars produced from oil palm and rice husks and their adsorption capacities for heavy metals

“…In Malaysia, the presence of heavy metals in the soil and water raises serious concerns, principally due to the acidic nature of the soil and water in the country, as heavy metals in acidic conditions are highly mobile (Matos et al 2001).…”

Metales pesados en suelos y sedimentos de la zona cañera del sur de Quintana Roo, México

“…Cada interacción química les confiere diferente comportamiento físico y químico, modificando así su movilidad, disponibilidad biológica y toxicidad. Al mismo tiempo, estos factores pueden ser afectados por las propiedades fisicoquímicas del suelo como la variación en el pH (siendo éste el más importante en la disposición de los MP), el contenido de materia orgánica (MO), la capacidad de intercambio catiónico (CIC) y la textura (FAR y PPIC, 1988;De Matos et al, 2001;Dube et al, 2001;Violante et al, 2010;Sherene, 2010;Kennou et al, 2015). Cuando los MP están disueltos en agua, la conductividad hidráulica resultante de la humedad y la porosidad del suelo, pueden influir directamente en la movilidad.…”

“…Se ha reportado que en el suelo la CIC y la MO juegan un papel importante en la retención de los MP y el pH en la disposición de éstos, y por ello, concentraciones altas de MP se relacionan con estos parámetros (De Matos et al, 2001;Dube et al, 2001;Clemente et al, 2008;Violante et al, 2010;Kennou et al, 2015;Chandrasekaran y Ravisankar, 2015). En cultivos de caña de azúcar se recomiendan productos como Algaenzims® y Amikrone® para mejorar las propiedades físicas, químicas y biológicas del suelo y ayudar en la retención de los nutrientes.…”

Sorption of Heavy Metals by Ferralic-Arenosol and Vertic-Luvisol: A Comparative Isothermal Study

“…As expected, the results revealed an important underlying role of soil type on sorption i.e soil properties such as specific surface area of clay particles as well as cation exchange capacity were influential in determining sorption process of metal ions. de Matos et al (2001) demonstrated the influence of soil properties on sorption processes of pollutants. Thus, ALVv with superior soil properties ( Table 2) had higher metal loading capacity than its counterpart.…”

“…It seems reasonable to link higher retention capacities of metal ions to cation exchange capacity (CEC) and particle specific surface area, values of which were greater in ALVv than GARo. Studies by Appel et al (2008), Bradl (2004) and de Matos et al (2001 demonstrated that heavy metal loading capacity is correlated to high specific surface area of clay particles. Metal-wise comparison based on Langmuir parameter Q max established a higher sorption capacity for Cr 3+ than Pb 2+ and Cu 2+ .…”