COMPARISON OF USING UNMANNED AERIAL VEHICLE AND SATELLITE MONITORING TO ASSESS THE CONDITION OF WINTER WHEAT STAND THROUGH NDVI VEGETATION INDEX.

The presented paper deals with the issue of assessing the condition of winter wheat (Triticum aestivum L.) stand during its development in the spring period. The field experiment was established in 2020; two plots sized 25 ha and 16 ha were selected with a model plant of winter wheat. In the spring period (BBCH 35 and BBCH 51), both plots were monitored using an unmanned aerial vehicle (UAV) and Sentinel 2 satellites. After the end of the monitoring, spectral analysis of pictures taken was made and a basic NDVI vegetation index was calculated. Subsequently, spectral maps with this vegetation indexes were prepared. In the initial stage of model plant growth (BBCH 35), Unmanned aerial vehicles exhibited a greater sensitivity of measured data and was able to detect local damage to the stands. Differences in the measured data between UAV and Sentinel 2 were decreasing with the increasing amount of Triticum aestivum L. biomass, and in the advanced stage of vegetation (BBCH 51), a moderately strong positive correlation (R > 0.65) was found between the data measured by UAV and Sentinel 2. The measured values showed that satellite images were less accurate in detecting the occurrence of plant biomass at the beginning of growth. On the other hand, they can be more effective than UAV with the increasing plant biomass as satellite technologies can cover a considerably large area of earth surface during a single flight. [ABSTRACT FROM AUTHOR]