Spatio-temporal monitoring of soil salinity and land cover changes using remote sensing techniques: Zaghouan case study (Tunisia)

Abstract

Expansion of salt-induced soil in agriculture lands is major cause of desertification and crop yield loss. Detection of salt affected soils and land cover changes assessment is crucial to better understand the correlations between diverse land cover units and salinity.Salinity variations at local scales can be studied using a combination of satellite image analysis and field measurements.The purpose of this study is to assess and detect the variations of salt content in the soil and land cover in the study area located in Zaghouan Governorate (Tunisia). This includes the examination of soil salinization effect on land cover change between 2017 and 2021.Satellite imagery has shown that the study area has different soil cover units.Based on the combination between satellite imagery analysis and soil sampling, findings reveal a slight correlation between salinity levels and land cover classes.The study of soil salinity changes shows that salt content rates increased from 5.44 % in 2017 to 6.7 % in 2021, while the land cover has reversely changed to 9.95 % for the same time period.Furthermore, results related to the relationship between SI and NDVI indicates that soil salinity changes have a significant and direct impact on land cover over time.In addition to in situ data, comparing Sentinel-2 and Landsat 8 satellite data shows a great potential for detecting and monitoring salt-affected soils