Vegetation Indexes and their Insights

Vegetation indices are widely used in remote sensing and precision agriculture to provide a more in-depth view of vegetation health and productivity and to track changes over time.

They are a spectral imaging transformation of two or more image bands to enhance analysis of various characteristics of vegetation, such as biomass, photosynthetic activity, and water stress.

The different indices provide different information, and by using a combination of indices, a more comprehensive understanding of the vegetation state can be obtained.

Some of the most commonly used vegetation indices include:

Vegetation Index Data and Analysis

How do these vegetation indices playout in the real world to enable constructive and predictive analysis?

RGB

The RGB image offers a true-to-life visualisation of the field. It provides an effective, at-a-glance view, but as you'll see, it does not provide the deep insights afforded by utilising various vegetation indices.

NVDI

The data set takes on a different look when switching to NDVI.

NDVI can be used to shows plant vigor. Values close to 1 show greater vegetation cover, while those nearer to 0 highlights areas with little vegetation, early stages of cultivation, bare soil, or diseased plants.

NDRE

High values of NDRE represent higher levels of leaf chlorophyll content. Soil typically has the lowest values, unhealthy plants have intermediate values, and healthy plants have the highest values.

OSAVI

OSAVI cancels out background soil values in early season growth when background soil is highly visible. Values can range from -1 to 1. High OSAVI values indicate denser, healthier vegetation, whereas lower values indicate less vigor.

GNDVI

As with NDVI, the values given by this index also range from -1 to 1. Values between -1 and 0 are associated with the presence of water or bare soil.

Images and data credit