Effect of hydraulic conductivity on soil moisture uptake under saline conditions for wheat crop

Abstract

Salinity in soil can decrease plant available water and cause plant stress. The pattern of root water uptake for wheat was studied for saline as well as non-saline condition using non-linear root water uptake model. Experiments have been conducted using a salinity level of 4 dS/m and freshwater condition. The effect of salinity on soil moisture has been studied by varying the crop coefficient as well as hydraulic conductivity. The correction factor to the crop coefficient approach is found to be unsuccessful. However, the correction factor to the hydraulic conductivity for a non-saline condition improves the simulation of soil moisture uptake in case of saline soils. The exponential form of the equation is established for the hydraulic conductivity to soil moisture relationship under salinity level and freshwater sample. The present work also substantiates that the non-linearity parameter of root water uptake model (O-R model) is successful in simulation of soil moisture depletion in the crop root zone and does not vary more than 10% in case of saline soils.

Keywords:

• salinity
• O-R model
• crop co-efficient
• hydraulic conductivity

Acknowledgement

This article is among the selected papers presented at the ‘Hydro-2012’ conference held at IIT Bombay on 7–8 December 2012 and short-listed by the Editor for publication in this Journal after re-review and revisions where necessary.