Evaluation on salinity level and Electrical Conductivity of salt-affected areas in ground level through Remote Sensing Techniques

Abstract

This study aims to develop evaluation methods on salinity level and Electrical Conductivity (EC) of salt-affected areas at ground level through Remote Sensing Techniques. The research methodology was divided into 1) analyzing data obtained from Landsat-8 satellite along with 3 formats of spectral indices, i.e., Salinity Index (SI), Brightness Index (BI), and Normalized Difference Salinity Index (NDSI); 2) conducting field survey to measure Electrical Conductivity (EC) of salt-affected areas in ground level; and 3) conducting linear regression analysis with analyzed data obtained from Landsat-8 satellite and electrical conductivity of salt-affected areas in ground level. The results revealed that SI had a relationship with EC of saline soil at ground level at the highest level with a Confidence Interval of over 70% (R2 = 0.758) and correlation coefficient over 80% (R= 0.870). From such a linear relationship, a map of the distribution of saline soil in the research area could be created. From the total research areas of 73.40 km2, distribution of salt-affected areas in ground level could be divided into 5 levels (calculated to be % per area), i.e., highest level (>16 ds/m), high level (8-16 dS/m), moderate level (4-8 dS/m), low level (2-4 dS/m), and none (area with no effect from saline soil in ground level) (0-2 dS/m) with value of 0.01%, 0.01%, 40%, 59.71%, and 0.01%, respectively.