Data from: Effect of soil pH and minerology on the sorption and desorption of phosphite and phosphate in Ultisols of the Southeastern Coastal Plain
Data files
This dataset is embargoed and will be released on Aug 14, 2025 . Please contact Joshua Padilla at vog.adsu@allidap.auhsoj with any questions.
Lists of files and downloads will become available to the public when released.
Abstract
The development of transgenic crop varieties capable of utilizing phosphite (Phi) as a phosphorus (P) source is a promising strategy to increase P use efficiency while decreasing reliance on phosphate (Pi)-based fertilizers. However, little information is available on Phi sorption and desorption in soils. We conducted batch experiments to investigate the sorption of Phi and Pi by three Ultisols from the Coastal Plain of the southeastern United States. At the soils' acidic field pH (pH 4.7–6.2), Pi had a higher affinity than Phi for soil solids, where maximum sorbed concentrations of Pi were an average of 44% greater than those of Phi. The sorption of both P species decreased when experiments were repeated adjusting soil pH to 6.5. More Phi than Pi was recovered during desorption experiments, indicating that Phi was more reversibly sorbed and, therefore, may be more plant-available than Pi. Multiple linear regression between calculated linear distribution coefficients (KD; 10 mg P L−1 input solutions) and soil properties suggested that amorphous Al- and Fe-oxides controlled Pi sorption. Alternatively, amorphous Al-oxides and gibbsite controlled Phi sorption. Our results show that a lower affinity of Phi than Pi in Ultisols could improve P availability for plant uptake of Phi-based fertilizers but may increase the risk of soil P buildup over time.
README: Data from: Effect of soil pH and minerology on the sorption and desorption of phosphite and phosphate in Ultisols of the Southeastern Coastal Plain
https://doi.org/10.5061/dryad.63xsj3v9w
The dataset includes phosphate and phosphite isotherms, maximum sorbed concentrations of phosphate and phosphite, calculated linear distribution coefficients, percent of phosphate and phosphite recovered during desorption experiments, and raw X-ray diffraction data.
Description of the data and file structure
All data are provided in a Microsoft Excel sheet. Separate tabs correspond to individual figures or tables and a labeled in the Excel sheet. All units are provided along with a brief description of the experimental methodology. Detailed methodology is provided in the manuscript. The provided data will allow the user to recreate all figures and calculated values presented in the manuscript.
The tab labeled "Figure 1" provides measured solution concentrations (mg/L) and calculated sorbed concentrations (mg/kg) of phosphate and phosphite by five soils. Full soil names (under the "Soil" column) along with their manuscript abbreviations (under the "Abbreviation in Manuscript" column) are provided. Experiments conducted at field pH or at pH 6.5 are indicated under the "pH Treatment" column.
The tab labeled "Figure 2" provides calculated maximum sorbed concentrations (mg/kg) of phosphate and phosphite by five soils. Full soil names (under the "Soil" column) along with their manuscript abbreviations (under the "Abbreviation in Manuscript" column) are provided. Experiments conducted at field pH or at pH 6.5 are indicated under the "pH Treatment" column.
The tab labeled "Table 2" provides calculated linear distribution coefficients (KD, L/kg) for phosphate and phosphite sorption by five soils. Calculated percentages of phosphate and phosphite recovered from each soil during desorption experiments are also given. Full soil names (under the "Soil" column) along with their manuscript abbreviations (under the "Abbreviation in Manuscript" column) are provided. Experiments conducted at field pH or at pH 6.5 are indicated under the "pH Treatment" column.
The tab labeled "Supplemental Figure S1" provides raw X-ray diffraction data for the bulk soils used in the study. The data are given as X-ray intensity (counts/second) vs. angle (2-theta).
Code/software
All data are provided in a Microsoft Excel sheet.