Assessment and geographic visualization of salinity of Tigris and Diyala Rivers in Baghdad City

Abstract

Abstract This study is performed to assess and geographically visualize (i.e., geovisualize) the salinities of the Tigris and Diyala Rivers in Baghdad City based on the water’s electric conductivity. Data are interpolated using ordinary kriging and inverse distance weighting (IDW) methods. Patterns are clearly defined, and it is possible to identify the geographic distribution of salinity levels across the rivers. The methods are statistically valid because the root mean square errors of results in all months are near-zero. This work indicates that as the waters of the two rivers stream through Baghdad City, the Tigris River’s inflow has a moderate salinity but subsequently becomes highly saline, whereas the salinity of Diyala’s inflow is very high but thereafter diluted to a high salinity level. The results of this study prove that the use of ordinary kriging and IDW interpolation to geovisualize environmental data is a highly effective and satisfactory tool for monitoring and analyzing surface water quality. The IDW is also observed to exhibit high prediction accuracy.