Procedures for routine analysis of soil phosphorus (P) have been used for assessment of P status, distribution and P losses from cultivated mineral soils. No similar studies have been carried out on wetland peat soils. The objective was to compare extraction efficiency of ammonium lactate (P-AL), sodium bicarbonate (P-Olsen), and double calcium lactate (P-DCaL) and P distribution in the soil profile of wetland peat soils. For this purpose, 34 samples of the 0-30, 30-60 and 60-90 cm layers were collected from peat soils in Germany, Israel, Poland, Slovenia, Sweden and the United Kingdom and analysed for P. Mean soil pH (CaCl 2 , 0.01 M) was 5.84, 5.51 and 5.47 in the 0-30, 30-60 and 60-90 cm layers, respectively. The P-DCaL was consistently about half the magnitude of either P-AL or P-Olsen. The efficiency of P extraction increased in the order P-DCaL<P-AL≤P-Olsen, with corresponding means (mg kg -1 ) for all soils (34 samples) of 15.32, 33.49 and 34.27 in 0-30 cm; 8.87, 17.30 and 21.46 in 30-60 cm; and 5.69, 14.00 and 21.40 in 60-90 cm. The means decreased with depth. When examining soils for each country separately, P-Olsen was relatively evenly distributed in the German, UK and Slovenian soils. P-Olsen was linearly correlated ( r =0.594, P =0.0002) with pH, whereas the three P tests (except P-Olsen vs P-DCaL) significantly correlated with each other (P= 0.0178≤0.0001). The strongest correlation ( r =0.617, P =0.0001) was recorded for P-AL vs P-DCaL) and the two methods were inter-convertible using a regression equation: P-AL=-22.593+5.353 pH+1.423 P-DCaL, R 2 =0.550.
|Original language||American English|
|Number of pages||5|
|Journal||Acta Agriculturae Scandinavica - Section B Soil and Plant Science|
|State||Published - 1 Jan 2004|
Bibliographical noteFunding Information:
This study was undertaken within the framework of the project: Programme for the prevention of diffuse pollution with phosphorus from degraded and rewetted peat soils (PROWATER-EVK1-CT-1999-00036) financed by The European Union.
- Extraction efficiency
- P distribution
- Soil profile