Strategies for soil amelioration using sulphur in salt affected soils

Abstract

Effective use of salt affected soils needs the development of the most efficient and suitable reclamation technology to optimize farm management and better crop yields. Different chemical methods and amendments are used to reclaim the salt affected soils and after reclamation such soils may be used for sustainable agricultural production. Choice of a chemical amendment depends on its availability, cost, handling and time of application. Application of sulfur is very effective technique to suppress the uptake of undesired toxic elements and to improve the quantity and quality of produce in salt affected soils. So, a three-year field experiment was carried out to evaluate the comparative reclamation efficiency of two sulfur sources, i.e elemental sulfur and gypsum to improve the soil conditions by reducing the salinity/sodicity impact and yield characteristics of rice and wheat crop. A saline-sodic field {(ECe = 6.10 dS m-1, pHs = 9.21 and SAR = 41.67 (mmol L-1)1/2, SO4-S = 16.0 (mg kg-1) and soil gypsum requirement (SGR) of 9.10 t ha-1 for 0-15 cm soil depth} was selected. The treatments included were: control, gypsum application @ 100 SGR, S application @ 25, 50, 57, 100 and 125 % of SGR. Statistical analysis of three-year pooled data showed that varying levels of sulfur and gypsum significantly improved soil properties and rice-wheat yield than control, however, gypsum @ 100% of soil GR was at par with S @ 125 and 100% of SGR in term terms of improving yield component of both test crops and reducing soil pHs, ECe and SAR. Efficiency of treatment could be arranged as gypsum @ 100% SGR = S @ 125 % of SGR= S @ 100% of SGR> S @ 75 % of SGR> S @ 50 % of SGR> S @ 25% of SGR>control.