Interlaboratory Comparison of Soil Phosphorus Extracted by Various Soil Test Methods
| Author | Peter J. A. Kleinman | |
| Author | A. N. Sharpley | |
| Author | K. Gartley | |
| Author | W. M. Jarrell | |
| Author | S. Kuo | |
| Author | R. G. Menon | |
| Author | R. Myers | |
| Author | K. R. Reddy | |
| Author | E. O. Skogley | |
| Date of acession | 2024-03-14T10:57:00Z | |
| Date of availability | 2024-03-14T10:57:00Z | |
| Date of issue | 2001 | |
| Abstract | The widespread use of soil phosphorus (P) data, either in the context of agronomic or environmental management, requires an explicit understanding of potential errors related to soil P testing. This study compares a variety of soil P extraction methods, each performed by 9 separate laboratories on 24 soils from across the United States. Soil clay content ranged from 0 to 47%, pH from 4.2 to 8.6, and Mehlich-3 P concentration from 2 to 205 mg kg21 . Average interlaboratory coefficients of variation (CVs) ranged from 0.11 to 0.22 for solution extracts (Bray-1 P, Fe-strip P, Mehlich-3 P, and Olsen P) and from 0.11 to 0.70 for saturated paste extracts (resin capsules and resin membranes, incubated for 2, 4, and 7 days). For soil tests based upon solution extracts, Olsen P exhibited the greatest variability among laboratories ðCV ¼ 0:22Þ; despite its reputed suitability for a wider range of soils than Bray-1 and Mehlich-3. Soil test data were highly correlated, with the lowest correlations occurring between Olsen and Bray-1 P or Olsen and Mehlich-3 P (r ¼ 0:77 and 0.84, respectively) and the highest correlations occurring between Olsen P and Fe-strip P or Mehlich-3 and Bray-1 P (r ¼ 0:94 for both correlations). Results indicate that some common soil test P protocols, when carefully conducted, yield data that may be reliably compared, such as in the compilation of regional and national soil databases. | |
| Citation | Kleinman, Peter J.A.; Sharpley, A. N.; Gartley, K.; Jarrell, W. M.; Kuo, S.; Menon, R. G.; Myers, R.; Reddy, K. R.; and Skogley, E. O., "INTERLABORATORY COMPARISON OF SOIL PHOSPHORUS EXTRACTED BY VARIOUS SOIL TEST METHODS" (2001). Publications from USDA-ARS / UNL Faculty. 544. | |
| URL | https://hub.ifdc.org/handle/20.500.14297/2890 | |
| Language | en | |
| Subject | Soil | |
| Title | Interlaboratory Comparison of Soil Phosphorus Extracted by Various Soil Test Methods | |
| Type | Article |