Water quality and potassium and sulphur contribution through groundwater irrigation in Bathinda district of Punjab

Groundwater is one of the major sources for irrigation in arid and semi-arid regions. Water quality information is important for the purpose of planning and management of water for irrigation. The tubewell water samples of different blocks namely Bathinda (95), Sangat (59), Talwandi-Sabo (93), Maur (34), Nathana (81) and Rampura-Phul (19) were collected and analyzed for water quality, potassium and sulphur content. The pH of water was higher in Nathana block followed by Talwandi-Sabo and Rampura-Phul. Highest electrical conductivity (4.2 dS m⁻¹) in tubewell waters was in Talwandi-Sabo followed by Maur and Bathinda blocks. Water samples from Rampura-Phul block showed maximum residual sodium carbonate (RSC, 2.80 meq L⁻¹) followed by Nathana (1.50 meq L⁻¹) and Talwandi-Sabo (1.34 meq L⁻¹). Irrigation with tubewell waters contributed maximum Nathana block. However, the SO₄-S addition was maximum (1.54 kg ha⁻¹) in Maur block followed by Talwandi-Sabo (1.43 kg ha⁻¹) and Sangat block (1.40 kg ha⁻¹) along with each irrigation by ground water. Depending on the number of irrigations applied, rice-wheat cropping system contributed maximum amount of K and SO₄-S in the soil followed by rice-mustard/barley > cotton-wheat > cotton-mustard/barley > mung/clusterbean-wheat > mung/clusterbean-mustard/barley cropping system in the district. Similarly, ricewheat cropping system contributes 2.1 times more K and SO₄-S than cotton-wheat cropping system, whereas, rice-mustard/barley contributes 2.4 times more K and SO₄-S than cotton- mustard/barley system in the district.