ABSTRACT
Soil physical properties and hydrological indices to predict saturated hydraulic conductivity in agricultural terraces in the Mixteca region of Oaxaca, Mexico.

Blanca E. Santiago-Mejia1, Demetrio S. Fernandez-Reynoso2*, Adolfo Lopez-Perez2, Martin A. Bolaños-Gonzalez2, Jacinta Palerm-Viqueira2, and Juan U. Avelar-Roblero3
 
The saturated hydraulic conductivity (Ks) is a key parameter for understanding water movement in soil. This property is closely linked to the physical properties of the soil and affects crop management for better development and productivity. In the Mixteca region of Oaxaca, Mexico, pre-Hispanic agricultural terraces are built in the beds of intermittent streams, known as Lama-Bordo Systems (LBS). The LBS helps trap suspended sediments, creating agricultural surfaces. The objective of this study was to correlate soil physical properties and hydrological indices to create a predictive model for estimating Ks, which contributes to its determination in areas with similar sedimentary deposition conditions such as the LBS. Observed mean Ks was 4.26 cm ha-1, ranged from 1.00 to 11.49 cm ha-1, while for calculated Ks the mean was 4.50 cm ha-1 and ranged from 0.59 to 14.80 cm ha-1. Finally, the clay fraction, bulk density, organic matter content, and stream power index (SPI) allowed for estimating Ks with an 82% reliability level. These findings highlight the relevance of soil physical properties in the capacity for water storage and flow, and consequently, in agricultural productivity.
Keywords: Gully agriculture, sediment transport index, sediments, stream power index, topographic wetness index.
1Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias, Campo Experimental Rio Bravo, 88900, Rio Bravo, Tamaulipas, Mexico.
2Colegio de Postgraduados, Campus Montecillo, 56230, Texcoco, Estado de Mexico, Mexico.
3Universidad Autonoma Chapingo, Division de Ciencias Forestales, 56230, Texcoco, Estado de Mexico, Mexico.
*Corresponding author (demetrio@colpos.mx).