Study on the quality of irrigation water in the talawaan irrigation channel using the Sodium Adsorption Ratio (SAR) Method

Abstract

The suitability of water for irrigation purpose can be determined using the Sodium Adsorption Ratio (SAR) method. The method describes the extent of sodium will be absorbed into the soil. This study aims to assess the water quality of the Talawaan river as a source of irrigation water using the Sodium Adsorption Ratio (SAR) method. The measurement was carried out by field observation at the tertiary channel and laboratory analysis of water samples obtained from the channel. The concentration of Na+, Ca2+, Mg2+ were calculating using the SAR. Sampling of Water quality parameters was determined using the Composite Sampling, then analyzed with the UV-Spectrophometry The data referring to the standard values from Ayers and westcott. The results showed that the Sodium Adsorption Ratio (SAR) at the Talawaan irrigation varied from 1.33 meq/l to 1.55 meq/l. These results meets the requirements of the Ayers and Westcott standard standard, which stated that SAR at less than 3 meq/L is good quality standard (table 2). SAR value affects soil conditions, especially related to soil structure and soil permeability and infiltration.