A comparative study on field scale demonstration of fly ash and pond ash for cultivation of maize-groundnut crops in sequence on a Wasteland

In India, the major source of energy is thermal power plants that contribute about 70% of the total energy requirement and produce a huge amount of fly ash per year. The fly ash and pond ash collected from the Ramagundam Super Thermal Power Station, India, were mixed with soil at different doses, 50, 100, and 200 t ha−1 separately to compare their impact on crop yield and soil characteristics. Ash application had a beneficial effect on the crop yield, apart from reduction in the required doses of chemical fertilizers by half of the recommended doses. Addition of ash resulted in a significant increase in the contents of N, P, K, S, Ca, Mg, and micro-nutrients in maize and groundnut crop produce. The uptake of toxic trace elements (Cu, Zn, Mn, Fe, Pb, and Ni) was below the threshold levels. The residual effect of ash on crop yield and the nutrient composition of the subsequent maize and groundnut crops was also significant. The overall beneficial effect of ash could be attributed to the improvement in the soil. The results indicated that both the ashes could be applied safely for reclamation of uncultivated wastelands and pond ash is found to be better than the fly ash