Chapter 5 - Mapping and monitoring of salt-affected soils: the contribution of geoinformation

Abstract

Soil salinity is one of the major threats around the world induced by both anthropogenic factors and natural processes, εspecially in arid and semi-arid regions and areas under agricultural exploitation. In addition, predictions from climate models suggest that changes in weather conditions that will occur in the future as a result of climate change effects will have a negative impact on soil salinity. Salt affects the soils’ diversity, vegetation health, and crop yield productivity; hence, there is an urgent need for global monitoring soil salinity extent. Traditional methods for mapping soil salinity are proven to be ineffective, especially over large areas, due to cost, time-consuming, and excessive needs of labor. A major component of geoinformation technologies includes Earth Observation (EO), which is a modern tool for identifying and mapping soils affected by salts with efficient and cost-effective techniques. Remote sensing (RS) is commonly used to assess and monitor the extent of salt-affected soils (SAS) using multispectral data at different temporal and spatial resolutions. As such, the use of satellite RS data contributes significantly in assessing SAS more accurately, rapidly, and quantitatively. Integration also of geographic information systems in SAS mapping allows the implementation of various approaches for visual interpretation, classification, and modeling for the identification of those soil properties. This information can be accommodated thus easily in the management procedures such as sustainable agricultural practices, rehabilitation, and reclamation. This chapter aims at providing a review on the SAS dynamics as well as its impact on soil’s key properties including soil organic carbon content for climate change mitigation. In this context, a critical reflection on the use of geoinformation technologies in support of mapping the spatiotemporal variability of soil salinity and sustainable agricultural management is also furnished.