LAUSR

The growth of plants and the quality and quantity of crop production depend on the uptake dynamics of water and mineral salts by the roots from the rhizosphere. This water and nutrient dynamics in the rhizosphere is still not well understood. In view of above a mathematical model is proposed to study the effect of water flux on the nitrate dynamics in the rhizosphere of a single maize root. The model incorporates the important mechanisms like diffusion and mass flow of solutes in the rhizosphere. The parameters like soil porosity, soil buffer power, radius of the root have incorporated in the model. Appropriate boundary and initial conditions have been framed based on the physical conditions of the problem. Coaxial circular sector elements have been employed to discretize the circular cross-section of the root. Galerkin finite element method has been employed to obtain the solution. The numerical results have been computed and used to study the effect of water flux on nitrate dynamics at the surface of the root and in the rhizosphere. The change percentage in nitrate concentration at the surface of the root in the rhizosphere of maize root due to change in water flux 10−7–10−6cms−1, 10−6–10−5cms−1 and 10−7–10−5cms−1 is observed to be 0.28–1.21%, 2.91–13.73% and 3.20–15.11% in μmolcm−3 respectively which is quite significant.