- Study impacts of ‘soil and water salinity’ on crop yield.
- Study the unequal distribution of water in the study area of Rajo Nizamani with respect to crop yield.
- Find out the new surface to groundwater ratios for farmers to attain crop yield more than 5 tons/ha.
Supervisor Name: Rakhshinda Bano, Assistant Professor, USPCAS-W, MUET, Jamshoro
Focusing on the wheat crop, this study aimed at identifying the appropriate ratios of ground and surface water used to obtain acceptable crop yield. It involved co-relating water and soil salinity with the crop yield and testing the water allocation for the study area of RajoNizamani. Data related to water demand and supply, crop yield and net return were collected through field surveys, while analysis of water and soil salinity was done through in-situ measurements of Total Dissolved Solids (TDS), using a TDS meter. It was observed that farmers on the right side to the water-course had more surface water availability than left side of the study area and had slightly higher crop yields.
Groundwater salinity was higher on the Left side of the study area compared to that of the Right side. Soil salinity was greater in the fields irrigated with the higher proportion of groundwater. The average wheat crop yields obtained for the year 2017 for farmers of Left and Right side of the study area were 4.137 tons/ha and 4.88 tons/ha, respectively. Using Tyagi’s linear regression model for the crop yield (2004), in R statistical software, crop yields of the study area were modeled against total irrigation (total supply of water), canal water percentage and soil and water salinity. Where, the first two parameters were observed to have a positive effect on crop yield, and other two (water salinity and soil salinity) negatively affected the crop yield, with the regression co-efficient of 0.049978, 0.005925, -0.187931 and -2.501899, respectively. Suitable groundwater usage values were obtained based on the difference between simulated and observed crop yield values.