The relationship between leaching fractions obtained under field conditions and soil water salinity profiles on nature alfalfa was studied by applying three qualities of water at three leaching fractions to areas of an alfalfa field (Medicago sativa L.) having three depths to water table. The electrical conductivity of the irrigation water and of the soil solution extract at various depths was measured for each irrigation. ET measurements from several lysimeters located in the field were used to determine depths of irrigation water to apply. A sprinkler irrigation system was used for application of the irrigation water to the plots, and the depth applied was determined by measuring the depth of water caught in cans placed in a sample plot during each irrigation.The electrical conductivity of the irrigation waters applied averaged 0.98 mmhos/cm, 2.22 mmhos/cm, and 2.80 mmhos/cm for the season. Leaching fractions for the low leaching treatment of each water quality averaged 0.003. The other leaching treatments ranged from 0.082 to 0.343. Assuming an inert soil with no precipitation or dissolving of salts, there should have been increases in average soil profile salinity ranging from 1.81 mmhos/cm to 5.45 mmhos/cm during the season depending on the treatment. The largest increase measured on any treatment was 0.32 mmhos/cm. Some treatments actually caused a decrease in salinity where an increase was expected. For the condition of this study it appears that soil profile salinity is relatively insensitive to leaching fraction for short periods of time (1 or 2 years). This is attributed to the high relative concentrations of calcium and sulfate in the irrigation water and soil solution. Bearing these factors in mind, it appears that the quantity of salt removed in the drainage water varies directly with the quantity of drainage water since the concentration is relatively constant.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.