Исследование влияния освещенности на расчет вегетационных индексов на примере NDVI

Abstract

The purpose of the research is to study changes of the values of vegetation indices of landscapes depending on their illumination. The most used vegetation index NDVI was chosen as an example. The NDVI index was calculated for the following natural objects: water surface, open soil, forest plantations and a field with growing agricultural crops. The vegetation index was calculated using multi- and hyper-spectral satellite images obtained from local satellite systems Resurs – P and Canopus – V and foreign satellite system Sentinel – 2. Satellite images were selected for the same territories, but completed at various values of cloud cover density. Different values of cloud cover density provided differences in the illumination of the landscapes depicted in the images. The difference between the dates of the space survey did not exceed five days. As a result of the research, a change in the index values was revealed in images of the same object taken under different light conditions. However, the results obtained during the research did not allow us to estimate the amount of the illumination influence on the values of the vegetation index. As one of the results, a program of a field flight experiment was proposed to determine the values of vegetation indices based on multispectral survey materials using UAV at known values of landscape illumination.