This title appears in the Scientific Report : 2015 

Speciation and distribution of P associated with Fe and Al oxides in aggregate-sized fraction of an arable soil
Jiang, Xiaoqian (Corresponding author)
Bol, R. / Willbold, S. / Vereecken, H. / Klumpp, E.
Agrosphäre; IBG-3
Analytik; ZEA-3
Biogeosciences, 12 (2015) 21, S. 6443 - 6452
Katlenburg-Lindau [u.a.] Copernicus 2015
10.5194/bg-12-6443-2015
Journal Article
Terrestrial Systems: From Observation to Prediction
OpenAccess
OpenAccess
Please use the identifier: http://dx.doi.org/10.5194/bg-12-6443-2015 in citations.
Please use the identifier: http://hdl.handle.net/2128/9563 in citations.
To maximize crop productivity fertilizer P is generally applied to arable soils, a significant proportion of which becomes stabilized by mineral components and in part subsequently becomes unavailable to plants. However, little is known about the relative contributions of the different organic and inorganic P bound to Fe/Al oxides in the smaller soil particles. Alkaline (NaOH–Na2EDTA) extraction with solution 31P-nuclear magnetic resonance (31P-NMR) spectroscopy is considered a reliable method for extracting and quantifying organic P and (some) inorganic P. However, any so-called residual P after the alkaline extraction has remained unidentified. Therefore, in the present study, the amorphous (a) and crystalline (c) Fe/Al oxide minerals and related P in soil aggregate-sized fractions (> 20, 2–20, 0.45–2 and < 0.45 μm) were specifically extracted by oxalate (a-Fe/Al oxides) and dithionite–citrate–bicarbonate (DCB, both a- and c-Fe/Al oxides). These soil aggregate-sized fractions with and without the oxalate and DCB pre-treatments were then sequentially extracted by alkaline extraction prior to solution 31P-NMR spectroscopy. This was done to quantify the P associated with a- and c-Fe/Al oxides in both alkaline extraction and the residual P of different soil aggregate-sized fractions. ...