Premium
ISOTOPICALLY EXCHANGEABLE PHOSPHORUS IN SOILS
Author(s) -
TALIBUDEEN O.
Publication year - 1958
Publication title -
journal of soil science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.244
H-Index - 111
eISSN - 1365-2389
pISSN - 0022-4588
DOI - 10.1111/j.1365-2389.1958.tb01904.x
Subject(s) - soil water , chemistry , phosphorus , fractionation , phosphate , calcareous , environmental chemistry , agronomy , soil science , geology , chromatography , biology , paleontology , organic chemistry
Summary Phosphate residues in the soil were subdivided into three fractions on the basis of isotopic exchange of orthophosphate ions between the soil and the soil solution. It was observed that the total labile phosphorus was a smaller fraction of the total phosphorus in the heavier soils ( c . 20 per cent. clay) than in the lighter soils (1–10 per cent. clay), This could be partly attributed to a higher organic‐phosphorus content in the heavier soils. In comparable soils, recent manuring with superphosphate increased the ratio of the rapidly labile phosphate to the total labile phosphate; in the soils of lower clay content, this ratio was higher than the corresponding ratios in the heavier soils. The recovery of phosphorus added at a moderately heavy rate was estimated by this method of fractionation in soils incubated for periods up to 3 months after treatment. Recovery of added phosphorus in the total labile fraction was incomplete for the calcareous soils, as compared to a I00 per cent. recovery in a neutral soil of similar clay content. Moreover, a redistribution of phosphorus with time was observed in the calcareous soils within the total labile fraction, no such effect being observed with the neutral soil. This was attributed to the presence of internal surfaces on the calcium carbonate present.