Determination of salt dynamics in leached water from cultivated onions (Allium cepa) under two irrigation systems in the Samacá-Boyacá Valley od Cely-Reyes, Germán Eduardo, Fernández-Pérez, Carlos Julio, Walteros-Torres, Ingrid Yaneth, Camargo-Guerrero, Fabiola del Rosario, Serrano-Cely, Pablo Antonio