Abstract
Background Diverse phosphorus (P) fractionation procedures presented varying soil P fractions, which directly affected P contents and forms, and their biological availability. Purpose To facilitate the selection of phosphorus (P) fractionation techniques, we compared two procedures based on a long-term experiment on a calcareous soil. Methods The soils containing a gradient P levels were sampled from seven treatments predictor under various long-term fertilizations. The P fractions were then separated independently with both fractionation procedures modified by Tiessen-Moir and Jiang-Gu. Results The results showed that the labile P in Jiang-Gu is significantly lower than that in Tiessen-Moir. The iron and aluminium-bounded P were greater in Jiang-Gu by a maximum of 46 mg kg−1 than Tiessen-Moir. Jiang-Gu fractionation gave similar Ca bounded P to that Tiessen-Moir did at low P level but greater contents at high P level. The two methods extracted much comparable total inorganic P. However, Tiessen-Moir method accounted less total organic P than ignition or Jiang-Gu method (the organic P (Po) estimated by subtract the total inorganic P (Pi) in Jiang-Gu fractionation from the total). P uptake by winter wheat was significantly and positively correlated with all phosphorus fractions in Jiang-Gu; Resin-P, NaHCO3-Pi, D. HCl-P, C. HCl-Pi, NaOH-Po, total-Po in Tiessen-Moir; P fraction categories of Ca-P, Fe & Al-P and total-Pi in both fractionations. Path coefficients indicated that Ca2-P in Jiang-Gu, NaHCO3-Pi and D. HCl-P in Tiessen-Moir had the higher and more significant direct contributions to P uptake among P fractions measured. Conclusions Our results suggested that Jiang-Gu procedure is a better predictor in soil P fractionation in calcareous soils, although it gives no results on organic P fractions.
Highlights
Phosphorus (P) is essential and generally considered as a constraining nutrient in most cases in natural ecosystems (Elser et al, 2007; Li et al, 2013)
Linear regressions were plotted to compare the Jiang-Gu versus Tiessen-Moir fractionation methods for categories of labile-P, Fe and Al bounded P, Ca-bounded P and total Pi (Fig. 2)
The slope of the linear regression of Fe & aluminum bounded phosphorus (Al-P) contents obtained from two fractionation methods was close to 1, but significant difference in intercepts indicated that these kinds of P were greater in
Summary
Phosphorus (P) is essential and generally considered as a constraining nutrient in most cases in natural ecosystems (Elser et al, 2007; Li et al, 2013). P exists in soils in inorganic and organic forms, and their availability are generally evaluated by soil P fractionation (Cross & Schlesinger, 1995; Negassa & Leinweber, 2009). Phosphorus fractionation method modified by Tiessen & Moir (1993) from that proposed by Hedley, Stewart & Chauhan (1982) took into account the fractions of both inorganic P and organic P and its availability to crops, and has been widely adopted to quantitatively evaluate soil P fractions and transformations under different soil types, cropping systems, tillage practices and fertilization management regimes (Cross & Schlesinger, 1995; Negassa & Leinweber, 2009; Yan et al, 2016; Braos et al, 2020). Our results suggested that Jiang-Gu procedure is a better predictor in soil P fractionation in calcareous soils, it gives no results on organic P fractions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: PeerJ Inorganic Chemistry
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
