Perspectives and insight toward solving flaws of vegetation indices

TL;DR

This paper discusses the limitations of current vegetation indices like NDVI, highlighting spectral variability in crops, and proposes the development of crop-specific indices based on visible spectral features to improve accuracy.

Contribution

It identifies key flaws in existing vegetation indices and suggests a new approach involving crop-specific spectral indices to better assess crop health.

Findings

Spectral fingerprint varies with crop age and conditions.

NDVI may not accurately reflect true crop greenness.

Crop-specific indices could enhance vegetation monitoring.

Abstract

This perspective manuscript addressed several unsolved questions in vegetation index calculation such as the variation of the spectral fingerprint of crops and the differences in absorbance and reflectance spectral patterns of the young and mature leaves. The spectral shift is evident due to temporal and spatial variations. It means a generalized index, NDVI based on a near-infrared, and a red wavelength cannot precisely express the true meaning of a crops vegetation index. Thus commonly used vegetation indices have high possibility to undermine the actual photosynthetic capability or greenness of crops. Therefore, a crop specific vegetation index based on spectral characteristics in visible regions might be necessary to overcome this limitation of vegetation indices.