Aerial spectral index analysis for differential management zone delineation in a maize field

Inhomogeneities of soil properties are responsible for within-field variations on plants’ growth and final yield. In this paper, initially, the variations of a Normalized Difference Vegetation Index (NDVI) field map obtained through a camera mounted on a drone were correlated with soil and plant properties measured in a typical maize cultivated field. Subsequently, the perspective of organizing the field into differential management zones through the NDVI was evaluated. The coefficient of variation for sand, silt, clay and soil organic matter content at five points was found to exceed 11% while the corresponding value for biomass and yield were greater than 14%, indicating significant spatial field soil heterogeneity and variations on plant growth. When correlated to NDVI, sand content exhibited a negative correlation (r=-0.86), while in the case of silt, clay, organic matter content, biomass and yield the correlation was positive (r>0.8). Lastly, the NDVI confirmed to be a powerful tool for the delineation of deferential management zones.