Exchange Reactions Between Phosphates and Soils: Hydroxylic Surfaces of Soil Minerals

Determination of Plant Available P in Soil

“…Once in the soil, the labelled P starts to mix with and will be diluted by the 31 P of the soil solution and equilibrates (Amer et al 1955;Di et al 1997;Frossard et al 2011). This phenomenon was already noted by McAuliffe et al (1947) (cited after Frossard et al 2011) who observed a decreasing concentration of 32 P added to a soil-solution system with time as a result from the exchange and dilution between 32 P in soil solution and 31 P in the soil solid. According to the authors, this indicated the presence of two different P pools in the soil: one is assumed to contain the fraction of readily exchangeable P forms, while the other one contains the fraction of less-exchangeable P (Frossard et al 2011).…”

Assessment of gross and net mineralization rates of soil organic phosphorus – A review

“…Traditional use of P radioisotopes in soil P studies Two radioactive P isotopes ( 32 P and 33 P) can be used to study P cycling in soil. Early observations on the isotopic exchange between 32 P (the tracer) added to a soil-solution system and 31 P (the tracee) located on the solid phase were made by McAuliffe et al (1947) and Wiklander (1950). Both studies were based on the concept that at equilibrium, the distribution of the tracer between solution and solid phase is similar to the distribution of the tracee, and both examined the reactions taking place before reaching this equilibrium.…”

Control of nickel availability by nickel bearing minerals in natural and anthropogenic soils

“…Thus, the values in the long term (E N 3 months ) reflect the poorly accessible metal located in the microporosity of soil aggregates and/or occluded in the crystal lattices of minerals (Echevarria et al, 1998;Lombi et al, 2003). As trace or other major elements (i.e., phosphorus) held in crystalline mineral or occluded in mineral lattices are poorly and slowly exchangeable (McAuliffe et al, 1947), the isotopically exchangeable pool refers mostly to the element retained through sorption and surface-complexation onto soil particles and may provide information as to whether the element is included or not in crystal lattices (Sarret et al, 2004). By identifying the Ni-bearing phases and their fate during soil processes in soils (e.g., weathering), it should possible to predict the potential mobility and bioavailability of Ni over the long term and to relate them to pedogenetic processes and soil functioning.…”