Phosphate (P) adsorption of 6 agriculturally- important Arizona soils was studied by use of adsorption isotherm experiments and with conventional Langmuir and Freundlich adsorption models. Adsorption experiments were conducted at 25°C where each soil was placed in a 10:1 (solution:soil) ratio using 0.01M CaCl₂ as a background solution. Each soil was subjected to 4 levels of inorganic P addition using Ca(H₂PO₄)₂H₂O as the P source. Use of the Langmuir model was significant in all cases (P ≤ 0.05) with r² values ranging from 0.93 to 0.99. Capacity parameter estimates obtained from the models indicated P adsorption potentials of up to 357 lb. acre⁻¹ (818 lb. P₂0₅ acre⁻¹) for the soils studied. Application of the Freundlich model revealed r² values of 0.88 to 0.99 with all models proving to be significant (P ≤ 0.05).
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/204831 |
| Date | 03 1900 |
| Creators | Silvertooth, J. C., Gardner, B. R. |
| Contributors | Silvertooth, Jeff, Isbell, Joan |
| Publisher | College of Agriculture, University of Arizona (Tucson, AZ) |
| Source Sets | University of Arizona |
| Language | en_US |
| Detected Language | English |
| Type | text, Article |
| Relation | 370077, Series P-77 |
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