GNDVI - Green Normalized Difference Vegetation Index
This index can be used to monitor the presence and activity of green vegetation. In particular is a vegetation index for estimating photo synthetic activity and is a commonly used vegetation index to determine water and nitrogen uptake into the plant canopy.
The values given by this index also vary between -1 and 1. Values between -1 and 0 are associated with the presence of water or bare soil. This index is mainly used in the intermediate and final stage of the crop cycle.
How is it calculated?
The GNDVI is the green vegetation index that uses the near infrared (NIR) and green band (GREEN) of the electromagnetic spectrum.
Generic Formula (R is the reflectance at the wavelengths (nm) denoted by the subscripts):
Formula by Sentinel-2 bands:
References:
Rouse Jr, J. W., Haas, R. H., Deering, D. W., Schell, J. A., & Harlan, J. C. (1974). Monitoring the vernal advancement and retrogradation (green wave effect) of natural vegetation (No. E75-10354).
Zarco-Tejada, P. J., Miller, J. R., Noland, T. L., Mohammed, G. H., & Sampson, P. H. (2001). Scaling-up and model inversion methods with narrowband optical indices for chlorophyll content estimation in closed forest canopies with hyperspectral data. IEEE Transactions on Geoscience and Remote Sensing, 39(7), 1491-1507.