Spatial and temporal behavior of soil salinity of the Manglaralto UPSE Support Center

Abstract

The study was carried out in agricultural areas of the Centro de Apoyo Manglaralto UPSE with an approximate surface of 11.6 hectares, located in the Manglaralto parish of Santa Elena canton, which has an annual rainfall of 385.2 mm and an average temperature of 23.4 ºC. The spatial and temporal behavior of soil and water salinity was evaluated through measurements of Electrical Conductivity (EC) at 40 sampling points at depths of 0 to 20 cm and 20 to 50 cm. The sampling was carried out in the months of december 2018 and may 2019. The analysis of 20 samples was carried out by means of two techniques, using saturation paste extract and a 1:5 soil-water solution, in order to find the best fitting model, which allowed estimating the EC values in saturated paste from EC laboratory measurements in a 1:5 soil:water solution. With the results obtained, the interpolation of the different thematic maps was carried out by means of the Moving Average method, where in soils at depths of 0 to 20 maximum tenors of 2.32 and 0.91 dS/m were found in the months of December and May respectively. At depths of 20 to 50 cm these values were higher. It is assumed that irrigation water with an average EC in October of 4.1 dS/m is one of the main sources of salt accumulation in soils, at the same time it produces the leaching of salts in irrigation seasons.