Soil salinity and vegetation cover change detection from multi-temporal remotely sensed imagery in Al Hassa Oasis in Saudi Arabia

Abstract

Detecting soil salinity changes and its impact on vegetation cover are necessary to understand the relationships between these changes in vegetation cover. This study aims to determine the changes in soil salinity and vegetation cover in Al Hassa Oasis over the past 28 years and investigates whether the salinity change causing the change in vegetation cover. Landsat time series data of years 1985, 2000 and 2013 were used to generate Normalized Difference Vegetation Index (NDVI) and Soil Salinity Index (SI) images, which were then used in image differencing to identify vegetation and salinity change/no-change for two periods. Soil salinity during 2000–2013 exhibits much higher increase compared to 1985–2000, while the vegetation cover declined to 6.31% for the same period. Additionally, highly significant (p < 0.0001) negative relationships found between the NDVI and SI differencing images, confirmed the potential long-term linkage between the changes in soil salinity and vegetation cover.

Keywords:

• Soil salinity
• vegetation cover
• differencing image
• change detection
• Al Hassa Oasis

Acknowledgements

The authors would like to gratefully acknowledge the data analysis support and assistance kindly provided by Catherine MacGregor from School of Environmental and Rural Science, University of New England. We would like to express our deep graduate to the editors and the two anonymous reviewers for their constructive comments and suggestions to improve the quality of the paper.