Preliminary exploration of potential ponding impact on crop vigour using remote sensing techniques

Water ponding could seriously compromise agricultural productivity in lowland landscapes. Indeed, water remaining on the surface after extreme rainfall and/or prolonged irrigation compromises soil functionality and crop vigour. Among the factors responsible for ponding, surface morphology plays a central role. Depressed areas that are not adequately connected to the drainage network and not processed to promote soil infiltration rate are susceptible to waterlogging. The advent of remote sensing opens up new opportunities in mapping and understanding the processes occurring on agricultural terrains. In this research, we propose the use of a geomorphological index (Relative Elevation Attribute; REA) capable of mapping areas potentially susceptible to water ponding and therefore challenged. Furthermore, through the application of the Normalized Difference Vegetation Index (NDVI) an evaluation of the impact of ponding on crop vigour is proposed. The results are promising, since in areas where ponding potential is high, NDVI values are generally lower, indicating that the phenomenon could compromise the functionality of agricultural soils in production. Therefore, remote sensing techniques could be used in designing sustainable solutions at a large scale and in specific hotspots, and further research along these lines is encouraged.