ABSTRACT.
Effect of twenty seven years of fertilization on chemical characteristics of an alluvial Mollisol soil irrigated by Maipo river, Chile

Angélica Sadzawka R.1, Rafael Novoa S-A.1 y Elías Letelier A.1
 

In order to evaluate the effects of long-term fertilization on the chemical characteristics of an alluvial Mollisol soil irrigated by Maipo river waters, soil samples under maize monocultive, fertilized during 27 years with sodium nitrate, triple superphosphate and potassium sulphate, were analized. Long-term fertilization increases available P, but it does not affect pH, electrical conductivity, available nitrogen, exchangeable sodium and potassium, sodium saturation and sodium adsorption ratio (SAR). These results were atributed to the combinated effects of calcium carbonate present in soil and higher concentration of calcium, in irrigation water, related to sodium and bicarbonate, which prevent either exchangeable complexe adsorption of fertilizer and water sodium and soil alcalinization.

Keywords: soil, long-term fertilization, chemical characteristics, irrigation water elements supplies.
1 Estacíón Experimental La Platina (INIA), Casilla 439, Correo 3, Santiago, Chile.