Premium
Phosphate Desorption from Soils and Sediments with Varying Levels of Extractable Phosphate
Author(s) -
Oloya Tom O.,
Logan T. J.
Publication year - 1980
Publication title -
journal of environmental quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 171
eISSN - 1537-2537
pISSN - 0047-2425
DOI - 10.2134/jeq1980.00472425000900030040x
Subject(s) - soil water , phosphate , chemistry , desorption , environmental chemistry , mineralogy , adsorption , geology , soil science , organic chemistry
Desorption of P from soils and sediments was studied using sequential (10‐cycle) batch equilibration in 0.01 M CaCl 2 for equilibration periods of 2, 60, 480, 1,440, and 5,760 minutes. Soils with high Bray P1‐extractable P contained a pool of easily desorbable P which was depleted by the fifth cycle. Stream suspended sediments, bottom sediments, and soils low in Bray‐extractable P released small, but constant, amounts of P. Desorption of P from high extractable P soils was independent of equilibration time for the first two equilibrations, but obeyed first‐order kinetics for the subsequent eight extractions. Phosphate desorbed from all soils and sediments was highly correlated with Bray P1‐extractable P. The sediments and Hoytville soils from Defiance County, Ohio, gave a linear relationship between Bray P1 and desorbable P, while the Hoytville soils from the tillage study gave a quadratic increase in desorbed P with increasing Bray P1‐extractable P.