**5. Conclusion**

As two global challenges without national borders, soil salinity and the water crisis endanger sustainable agricultural production through decreasing farmland productivity and crop yield [153, 154]. These principal abiotic stresses significantly restrict crop productivity by inhibiting metabolic activities and disturbing the ionic balance. Water deficits caused by osmotic stress severely reduce the crop yield, which drives considerable economic losses for farmers. Hence, monitoring their changes in farmlands using sensors is crucial due to the significant regional or national financial loss caused by drought and salinity. Despite soil moisture and salinity probes effectively measuring soil parameters, inefficient performance in broad fields plus the high cost and low accuracy have accelerated the application of new remote sensing technologies. Satellites and UAVs have the possibility of monitoring these variables on a broad scale. However, low spatial resolution, difficulty of use, the need for technological operators, and lengthy data processing make them unpopular with farmers, particularly in rural regions. In addition to remote sensing, IoT technology combines sensor systems and web-based software that transfers soil moisture and salinity data to a computer or mobile phone. While precision agriculture is gradually developing new technologies in farmlands, more extensive investigations are needed to address the challenges of agricultural digitalization.

*An Overview of Soil Moisture and Salinity Sensors for Digital Agriculture Applications DOI: http://dx.doi.org/10.5772/intechopen.103898*
