Testing Alternative Techniques of Numerical Simulation versus Repeated Field Instrumental Measurements for Assessing Soil Salinity Status in a Sodic Grassland

Within a 300 x 600 m complex heterogeneous sodic grassland two techniques were compared for assessing soil salinity. The standard technique is based on repeated field instrumental measurements at 420 points. The alternative technique was performed with the use of numerical simulation of salt accumulation carried out on 3 profiles. These profiles have been selected as representatives of the distinct classes, or map strata of salt accumulation, distinguished with preliminary statistical clustering of the instrumental measuring points. Simulated values were extrapolated for the 3 strata distinguished. The maps obtained with the two techniques were statistically correlated. The use of numerical simulation is cost-effective. Further improvements are expected from a combination of improved numerical simulation and utilization of more strata.