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Table 2 Bulk soil chemical analysis and XAS linear combination fitting results for the second application of TPP

From: Chemical speciation and fate of tripolyphosphate after application to a calcareous soil

Label Depth (m) Soila pH Total Elemental Concentrationsb Ca:Mg ratio Labilec extractable P (mg/kg soil) LCF analysis resultsd,e Reduced chi2
Ca (mg/kg soil) Mg (mg/kg soil) P (mg/kg soil) Fe (mg/kg soil) Adsorbed P (%) Ca-P species (%)f
1b 1.82 7.8 22,800 15,200 820 24,700 1.5:1 74 10 96 0.00743
2b 3.66 7.8 29,900 17,300 870 27,300 1.7:1 79 24 76 0.00192
3b 1.82 7.8 24,800 14,100 790 25,000 1.8:1 71 18 81 0.00074
4b 3.66 7.4 23,900 15,900 880 29,600 1.5:1 60 41 61 0.00104
5b 1.82 7.9 22,200 13,800 750 25,200 1.6:1 85 43 57 0.00117
6b 3.04 7.9 1340 3140 3230 16,700 0.4:1 85 63 40 0.00139
7b 3.66 7.6 49,700 29,400 780 29,400 3.2:1 82 32 70 0.00140
8b 1.82 7.8 25,300 15,300 880 26,700 1.7:1 19 31 71 0.00130
9b 3.66 7.8 26,300 17,000 920 28,100 1.5:1 27 36 63 0.00155
10b 1.82 7.8 33,000 15,100 960 26,900 2.2:1 24 42 61 0.00059
11b 3.66 7.5 18,100 14,400 1000 39,200 1.2:1 62 31 70 0.00100
  1. aSoil pH accurate to ± 0.1
  2. bVia total XRF elemental analysis, concentrations are accurate to ± 10%
  3. cCombination of H2O and NaHCO3 extractable P
  4. dEo Shift constrained to zero
  5. e% Relative contribution to XAS signal; models are unconstrained and not equal to 100%
  6. fRelative sum of the contribution from calcium phosphate mineral species