Clay minerals, iron/aluminum oxides, and their contribution to phosphate sorption in soils — A myth revisited

Chemical Distribution of Phosphorus in Soils used during the Development of Sorption Isotherms

“…Furthermore, the amount of phosphate that can sorb on the same mineral will change as the pH of the material changes (Gérard, 2016). It has been reported that changes in the pH of clay minerals have a larger impact on phosphate sorption than pH changes of Fe or Al oxides (Gérard, 2016). The wide range in the properties measured suggests that the results of this study would be applicable to agricultural soils that fall within the range of soil properties used here.…”

“…The physicochemical properties reported in Table 1 were selected because these are the properties most often reported as affecting the sorption properties of soils (Hinsinger 2001;Laboski and Lamb 2004;Allen and Mallarino 2006;Devau et al, 2011;McLaughlin et al, 2011;Eriksson et al, 2015). For example, soil pH and clay content are reported to have a strong relationship with the P sorption capacity of soils, as they are related to the amount of Al, Fe, and Ca present in the soil solution (Violante and Pigna, 2002;Devau et al, 2011;Bair et al, 2014;Eriksson et al, 2015;Gérard, 2016). However, the effects of pH on P sorption are much more complex because during exchange reactions, OH -groups are replaced with phosphate ions, causing a pH change in the vicinity of the reaction.…”

“…However, the effects of pH on P sorption are much more complex because during exchange reactions, OH -groups are replaced with phosphate ions, causing a pH change in the vicinity of the reaction. Furthermore, the amount of phosphate that can sorb on the same mineral will change as the pH of the material changes (Gérard, 2016). It has been reported that changes in the pH of clay minerals have a larger impact on phosphate sorption than pH changes of Fe or Al oxides (Gérard, 2016).…”

“…In the soil, inorganic P (P i ) will adsorb or precipitate by chemically binding with Al, Fe, or Ca (Lombi et al, 2006;Khatiwada et al, 2012;Eriksson et al, 2015). The solubility of phosphorus in soil is controlled by several factors, including how much P is originally adsorbed in the soil, how much P is precipitated in the soil, the soil pH, clay mineralogy, organic matter content, what types of minerals were formed during P precipitation, and the concentration of Ca, Al, Fe, and other cations in solution (Delgado and Torrent 2000;Violante and Pigna, 2002;Shigaki and Sharpley 2011;Weng et al, 2012;Eriksson et al, 2015;Gérard, 2016). McLaughlin et al (2011) has shown that the amount of Ca, Al, and Fe, in the soil solution controls P solubility and mobility from the inside of the fertilizer granule to the surrounding soil particles.…”

Plant growth, nutrients and potentially toxic elements in leaves of yerba mate clones in response to phosphorus in acid soils

“…The low pH of very acid soils can affect the soil element dynamics, especially the increase of Cu, Fe, Mn, Ni, Zn, Al, Pb and Cd availability, and the decreased Mo and P availability (Kabata-Pendias 2011). The soil P availability undergoes interference of clay mineral specific adsorption (Gérard 2016). In the case of low soil P availability, plants increase the root exudate molecules that solubilize non-available forms of P, which can solubilize other nutrients or toxic elements.…”