Abstracto

The Leaching Kinetics of Nitrate in Soil Using Glass Column Method

Anuj Kumar Garg, A. K. Gupta, Ashu Rani

The leaching kinetics of nitrate (NO3 -) in agricultural (pH = 7.2) and non-agricultural soils (pH = 6.8) was studied using undisturbed glass columns method . The soils were taken from the agriculture field and barren land near Dheerkhera agricultural area, Hapur. The Sodium nitrate (NaNO3) is used as a source of NO3 -. Power form equations (LRobs = k1 [NO3 - ]i 2.91 for agricultural and (LRobs = k2 [NO3 - ]i 1.829 for non-agricultural soils have been derived for dependence of LRobs on leachable concentration of NO3 - present initially. The effects of pore volume, temperature, Ca hardness have been observed on leaching rate. Change in water filled porosity θ (cm3cm-3) of the column has been found to affect LRobs. The LRobs is found to increase with temperature in the range 30-50°C. Experimental data fitting on various kinetic models showed first order kinetic models and parabolic diffusion to be most suited for predicting leaching rates.