Beschreibung:
SUMMARYThe Q/Icurves for Na in the Na–Ca system in some salt‐affected soils of Malaprabha and Ghataprabha river valleys lacked the curvature commonly seen in the Q/I curve for potassium. The Malaprabha soils showed lower AR0Na, NaL and BC0Na values and higher energies of replacement of calcium by sodium than the Ghataprabha soils; the latter showed a higher affinity for Na than Ca. Two distinct linear parts of the quantity/ potential curves, with different slopes, indicated that Na is held in these soils in two characteristic types of exchange sites having different affinities for sodium. The intersection of the two linear parts corresponded to ESP values in the range of 13 to 64%. The change in the affinity at such a high degree of Na saturation was attributed to the presence of chloritized smectitic clays and sodium‐selective zeolite, such as analcite, reported in these soils.