Estimation of Nitrogen in the Soil of Balsa Trees in Ecuador Using Unmanned Aerial Vehicles

The use of remote sensing considering Unmanned Aerial Vehicles (UAV) is a recent alternative to collect data from different fields. One of the applications is related to soil parameter estimation considering different multispectral vegetation indexes. The typical use is to establish a relationship between the plant health and a vegetation index. However, this is a simple estimation where is not considered any field (soil) validation or real parameter estimation. Thus, this work aims to establish a model to estimate the percentage of nitrogen (N) in the soil, using vegetation indexes obtained from UAV and soil field measurements under balsa trees in Ecuador. The results show a high correlation between the Green Normalized Difference Vegetation Index (GNDVI) and the soil-nitrogen in comparison with other vegetation indexes, as the Normalized Vegetation Index (NDVI). Thus, this methodology allows to estimate the percentage of N to optimize the balsa production.