Effect of soil gypsum content and water quality on the gypsum distribution and some ions in horizontal soil column under unsaturated flow conditions

Abstract

A laboratory experiments were conducted to study the gypsum distribution and Cl-,Na+,Ca2+,SO42- ions inside Soil column, soil samples with different gypsum content (117.8, 316.8, 515.8 gm.Kg-1) where used to determined horizontal flow with water solution (EC5.0 SAR0,EC5.0 SAR15) under the continuous and dual addition were chosen to estimate gypsum content and ions concentration along soil columns in accordance with the methods proposed by American Salinity Laboratory.The results showed that Cl1- and Na concentration increased with decrease the soil gypsum content and it decreased with increasing in distance . Cl-1 and Na concentration increased with SAR increasing. Ca+2 and SO4-2 concentration increased with increasing in soil gypsum content and it decreased with increasing in distance, during dual addition but it decreased under continuous addition system.The soil gypsum content increased with distance for all treatments, and it decreased with increasing in SAR under dual addition comparing with continuous addition system.

Keywords

soil, column, flow, conditions