Using Satellite Remote Sensing Monitoring in Boosting Water Resource Substitutability in Agriculture

Agriculture plays a crucial role in the economy of every country worldwide. It also has significant implications for food security. In semi-arid regions, where agricultural development is hampered by various constraints such as drought, water management conflicts, resource scarcity, and overexploitation of aquifers, it is important to characterize and monitor the condition of land surfaces. About 60% of water resources are used by agriculture, although with limited efficiency. Monitoring and controlling the health and maintenance of soil, plant cover, and biodiversity are essential factors in ensuring the sustainability of agriculture. In areas characterized by significant water resource scarcity, accurate assessment of the water status of land surfaces is crucial for informed decisions on effective resource management, particularly in crop irrigation. In this context, remote sensing provides essential data for the observation of surfaces and is an important tool for obtaining information from a distance. Earth observation satellites provide a comprehensive view that helps better monitor and understand the challenges facing our rapidly changing world. This chapter discusses specific case studies of countries or regions, particularly those characterized by semi-arid and arid climates, such as Africa. The aim is to increasingly exploit advances in using satellite data and to contribute to the assessment of the potential of the new satellite sensors Sentinel-1 (S-1) to Sentinel-2 (S-6) for surface characterization, soil moisture, in sustainable water and land resource management. These new systems now offer operational products that feature high temporal repeatability and metric spatial resolution, enabling regular monitoring. In this context, radar data are sensitive to surface conditions, including soil moisture, surface roughness, and vegetation. They prove to be the most promising tools for precise monitoring at the property or regional level.