C. P. Devatha
National Institute of Technology Raipur, India
DEVATHA Chella Purushothaman is an Assistant Professor, Department of Civil Engineering, NIT Karnataka. She acquired her Ph.D degree in –Civil and Environmental Hydraulics Engineering in the year 2005. She specializes in Modeling of soil moisture in unsaturated zone, Ground water modeling, Remote sensing and GIS applications to Hydrology and Water resources Engg., Flood Modelling, Contaminant Transport Modelling, Design of Water Supply Networks, Modelling of Advanced Waste Water Treatment system.
The essence of salinity problem starts from the fact that all irrigation waters contain some amount of dissolved salts. Soil water salinity is dependent on soil type, climate, water use and irrigation. Root water uptake pattern for paddy is studied for saline as well as non-saline conditions in the present study using non-linear root water uptake model. Experimental work had been carried out using two different levels of salinity (4dS/m and 6.25dS/m) and fresh water condition. Salinity effect on soil moisture had been studied by two approaches viz., effect on crop efficient and effect on hydraulic conductivity. Based upon the experimental observation for less saline (4dS/m), high saline (6.25dS/m) and fresh water condition, exponential form of equation is established for the hydraulic conductivity. The results obtained for soil moisture depletion in the crop root zone shows significant improvement in simulation for saline cases with the use of non linearity parameter.
Keywords: Salinity, O-R model, Crop co-efficient, Root water uptake, Hydraulic conductivity.