African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6578

Full Length Research Paper

Characterization of soils affected by salts in irrigation district 110 “Río Verde”, Oaxaca, Mexico

  Sánchez-Bernal Edgar1*, Camacho- Escobar Marco2, Rodriguez-León Anastacio2 and Ortega-Escobar Manuel3
  1Institute of Ecology Universidad del Mar, Puerto Escondido, Oaxaca 71980, Mexico. 2Institute of Industrial Universidad del Mar, Puerto Escondido, Oaxaca, 71980, Mexico. 3Hydro-science Program, Postgraduates College, Montecillo, Mexico.
Email: [email protected]

  •  Accepted: 28 November 2011
  •  Published: 29 February 2012

Abstract

The central soils of the Irrigation District 110 Río Verde, Oaxaca, Mexico, present salt accumulation problems in the upper layers. This study evaluated some of their physicochemical characteristics, levels and type of salinity. In the dry season soil samples were collected from five randomly established profiles. These are alluvial soils at around 2.0 m depth, derived from weathered metamorphic rocks; silty loamy to loamy-silt-clay texture, changing to sandy as they approach the sea. The drainage is moderate to light in the upper horizons and decreases with depth, whereas the water table is shallow (1.8 m) and the pH is slightly alkaline to alkaline. The color varies with the content of organic matter and water in each soil. The poor natural drainage, shallow groundwater and irrigation with moderately saline waters has produced a gradual process of secondary salinization. The soils are affected in their upper layers by a hydrochloride salinity induced by NaCl and Na2SO4, more intense in soil profile four, whose electrical conductivity of the saturation extract > 6.0 dS m-1 and exchangeable sodium percentage > 20%, limit the growth and development of cultivated plants. Arenosols show no problems of salinity or sodicity.

Key words: Alluvial soils, electrical conductivity, osmotic potential, hydrochloride salinity, sodicity.