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Phosphorus (P) is essential for plant growth, but excessive and continuous application of P fertilizers and animal manure has led to the accumulation of legacy phosphorus (legacy-P) in soils. While legacy-P presents a potential resource to support future agricultural demands, limited understanding of its chemical forms across different soil types hinders its sustainable management. This study aimed to characterize the chemical nature and storage potential of legacy-P in three contrasting soil types: acidic, organic, and calcareous. Key soil properties—including pH, organic matter, total P, Mehlich-3 P, and concentrations of aluminum (Al), calcium (Ca), iron (Fe), and magnesium (Mg)—were evaluated alongside P fractionation using a modified Hedley method. Furthermore, the soil P saturation ratio (PSR) was calculated to evaluate the relative saturation of soil sorption sites with P. Results showed considerable variability in Mehlich-3 P across soil types, ranging from 7–62% of total P in acidic soils, 1–8% in organic soils, and 3–47% in calcareous soils. Acidic soils were dominated by humic/fulvic-bound P (> 42%), organic soils by recalcitrant residual P (> 62%), and calcareous soils by Ca/Mg-bound P (> 69%), highlighting the influence of soil chemistry on P stability. Despite considerable variation among soil types in P fractionations, PSR results suggested that Ca/Mg-associated minerals play a greater role in retaining legacy P in organic and calcareous soils than Al- and Fe-associated minerals. In acidic soils, both mineral groups contributed similarly to P retention.
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This content will become publicly available on October 22, 2026
The interplay of antiaromaticity and diradical character in diarenoindacenes and diindenoarenes
This perspective describes our efforts on how to rationally alter the electronic and magnetic properties of a class of inter-related quinoidal/diradicaloid molecules by judicious structural modification.
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- Award ID(s):
- 2246964
- PAR ID:
- 10680117
- Publisher / Repository:
- Royal Chemical Society
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 16
- Issue:
- 41
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 19026 to 19047
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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