Soil Salinity Mapping and Monitoring in Arid and Semi-Arid Regions Using Remote Sensing Technology: A Review

Abstract

Soil salinity is a serious environmental problem especially in arid and semiarid areas. It either occurs naturally or is human-induced. High levels of soil salinity negatively affect crop growth and productivity leading land degradation ultimately. Thus, it is important to monitor and map soil salinity at an early stage to enact effective soil reclamation program that helps lessen or prevent future increase in soil salinity. Remote sensing has outperformed the traditional method for assessing soil salinity offering more informative and professional rapid assessment techniques for monitoring and mapping soil salinity. Soil salinity can be identified from remote sensing data obtained by different sensors by way of direct indicators that refer to salt features that are visible at the soil surface as well as indirect indicators such as the presence of halophytic plant and assessing the performance level of salt-tolerant crops. The purposes of this paper are to 1) discuss some soil salinity indicators; 2) review the satellite sensors and methods used for remote monitoring, detecting and mapping of soil salinity, particularly in arid and semi-arid regions; 3) review various spectral vegetation and salinity indices that have been developed and proposed for soil salinity detection and mapping, with an emphasis on soil salinity mapping and assessment in arid and semi-arid regions; and 4) highlight the most important issues limiting the use of remote sensing for soil salinity mapping, particularly in arid and semi-arid regions.

Soil Salinity Mapping Using Multitemporal Landsat Data

“…The development of saline soils is a dynamic phenomenon, which needs to be monitored regularly in order to secure up to date knowledge of their extent, degree of severity, spatial distribution, nature and magnitude. For monitoring dynamic processes, like salinization, remotely sensed data has great potential; it uses aerial photography, thermal infrared or multispectral data acquired from platforms such as Landsat satellite (Allbed and Kumar, 2013). Previously, soil salinity has been measured by collecting soil samples in the region of interest, and then the samples were analyzed in laboratory in order to determine the amount of electric conductivity in the soil but this method was time and cost consuming.…”

Comparative Study among Different Semi-Empirical Models for Soil Salinity Prediction in an Arid Environment Using OLI Landsat-8 Data

“…Excess of salt concentration in soils affects significantly plant growth, crop and palms trees production, soil and water quality, and consequently soil erosion and land degradation [1] [2] [3]. Its impacts affect not only the environment, but also the economic aspects [4].…”

Challenges in Using Precision Agriculture to Optimize Symbiotic Nitrogen Fixation in Legumes: Progress, Limitations, and Future Improvements Needed in Diagnostic Testing

“…Traditionally, soil salinity has being measured using electrical conductance of soil solution extracts, electrical resistivity (ER), electromagnetic induction (EM) and time domain reflectometry (TDR) ( Table 2) [81,82]. Soil salinity has been mapped based on precision agricultural methods, including multispectral satellite sensors, hyperspectral sensors, and vegetation indices, e.g., NDVI, the soil adjusted vegetative index (SAVI), the ratio vegetative index (RVI), the brightness index (BI), the green vegetation index (GVI), and the wetness index (WI) [103]. Spatial as well as temporal mapping of salinity help in site-specific management to mitigate this major environmental problem.…”