Department of Soil Science and Agricultural Chemistry, Birsa Agricultural University, Ranchi, Jharkhand, 834006.
*Corresponding author.
The sulphate adsorption-desorption by the experimental soils showed that Alfisols (Haplustalfs) of Dumka District followed the Langmuir and Freundlich adsorption isotherms. Adsorption maxima (b), bonding energy constant (K) and maximum buffering capacity (MBC) of the soils decreased with the increase in sulphur levels varying from 282 to 338 mg kg−1, 0.0218 to 0.015 L mg−1 and 4.31 to 5.17 L kg−1, respectively. The Freundlich constants (k and 1/n) also decreased with the increase in sulphur levels. Results further revealed higher value of MBC in control as well as low S level plots than in the high S level plots. The amounts of sulphate extracted by KH2PO4 (500 mg P L−1) varied considerably with the sources and the levels of sulphur and increased with increasing amounts of sulphate sorbed. Desorption of S varied from 82 to 86% of the sorbed sulphur.
Sulphate sorption capacity, sulphate affinity constant, maximum buffering capacity, Alfisol
