Evaluación de la granulometría de la subcuenca de río Cebadas: Comparación de dos técnicas para la determinación

Abstract

The aim of the research was the granulometric evaluation of Cebadas river sub-basin soils, specifically the Ozogoche and Atillo river micro-basin through the application of the Bouyoucos-Day and Pipette methods to be compared in terms of variability, use and cost-benefit. In Ozogoche, samples were selected at depths of 0.30 and 0.60m and a profile from 0 to 3.5m and for Atillo at depths of 0.30 and 0.60m and a profile from 0.30 to 4.50m. Once in the laboratory, the particle size distribution was determined using Stokes' Law methods that provide qualitative and quantitative information; The quantitative information was statistically analyzed using Shapiro-Wilk, Wilcoxon and Student's test. To identify important differences at a significance level of 5%, it was necessary to use R Studio program which revealed that the methods are different from each other as to variability of granulometric fractions; Furthermore, in qualitative terms and on average, the soils of Ozogoche and Atillo river micro-basin which were sampled at depths of 0.30 and 0.60m were “sandy” due to the sand predominance over 70%, and “sandy loam” due to the slight increase in silts and clays in certain horizons. In addition, some protocols with appropriate procedures for the granulometric distribution analysis were established based on the NTE INEN ISO-IEC 17025: 2018 norm. It was concluded that the Bouyoucos-Day method was the most used to determine the percentage of sand, silt and clay in agricultural, environmental and construction areas. It also has a service cost which was three times lower than the one of the Pipette. It was recommended to extend the application of these methods in areas with more varied characteristics.