Amelioration of Vertisols with sand for management of soil physical, chemical and hydraulic properties in South India

Sand can be used for increasing water intake capacity and reduce dispersion ratio in a Vertisol. A study was conducted at Bellary, India with amended soil with 12 sand and soil mixtures ranging from 0:1 to 1:1 ratio on weight basis. The analysis indicated significant decrease of available water; plastic and liquid limits; dispersion ratio; available N, P and K; and increase in bulk density with increase of sand in mixture. The increase in hydraulic conductivity was below, 1.0 cm/hr^-1 upto 0.4:1 ratio and increased significantly to 3.63 cm/hr with increase in sand. The changes were assessed based on a regression model of soil and sand ratios. Each parameter was assessed using weighted scores based on linear scoring method. The sum of scores indicated that 0.4:1 of sand and soil was superior for different parameters. The ratio was also superior for retaining soil moisture for a longer period in Vertisols.