Proton release by N2‐fixing plant roots: A possible contribution to phytoremediation of calcareous sodic soils

Abstract With a world‐wide occurrence on about 560 million hectares, sodic soils are characterized by the occurrence of excess sodium (Na + ) to levels that can adversely affect crop growth and yield. Amelioration of such soils needs a source of calcium (Ca 2+ ) to replace excess Na + from the cation exchange sites. In addition, adequate levels of Ca 2+ in ameliorated soils play a vital role in improving the structural and functional integrity …