Reclamation of saline-sodic soils through cultural management under tile drainage system

Thousands of productive hectares of agricultural land have become unproductive owing to spread of waterlogging and salinity. Horizontal and vertical drainage has been provided to the affected soils for control of these problems. However, drainage alone is not enough for control of the twin menace of waterlogging and salinity, therefore, requiring something beyond drainage to keep the salts within limits. Cultural management is known to be more economical as compared to chemical amendments. Increasing the seed rate, raising crops on furrows and other tillage operations have marked effects on the reclamation process of soils. A research study on cultural management for reclamation of saline-sodic soils in lower Indus was conducted for three years under tile drainage system. The treatments tried were: T1,=Control, T2=Three ploughing and levellings, T3=Deep ploughing with levelling and T4=Wheat with high seed rate and cotton on ridges. These treatments were replicated thrice in Complete Randomized Block Design (CRBD). ECe, pH, SAR and ESP were decreased in T2, T3 and T4. The highest decrease in these parameters was 49, 10, 33 and 32 percent, respectively in T3 (Deep ploughing). In T4 these values decreased to 38, 6, 26 and 25 percent. T2 produced a decrease in ECe, pH, SAR and ESP to the level of 23, 4, 14 and 13 percent. However, under control treatment (T1), ECe, pH, SAR and ESP of the soils increased to 82, 12, 71 and 67 percent, respectively. The significant increase in yields from different treatments was recorded. T3 (Deep ploughing) produced higher average cotton yield of 2.63 tonnes per hectare followed by T4, T2 and T1 of 2.15, 1.91 and 1.57 tonnes per hectare, respectively. The same trend was observed in wheat yields. T3 produced 2.85 tonnes/ha of grain followed by T2, T4 and T1 at 2.31, 2.25 and 1.85 tonnes per hectare. The lowest yields were recorded in control treatment where cotton and wheat were cultivated under usual practices. Reduction in soil salinity, combined with appreciable increase in crop production, is possible in saline soils through the use of deep ploughing.