What is NDVI in agricultural surveys?
The Normalized Difference Vegetation Index (NDVI) is a numerical indicator that utilizes the electromagnetic spectrum's visible and near-infrared bands used to analyze remote sensing measurements and determine whether or not the object observed includes live green vegetation.
Normalized Difference Vegetation Index (NDVI) Uses to quantifies vegetation by determining the difference between the two near-infrared (which is hugely reflected by vegetation) and red light (which is absorbed by vegetation).
NDVI is usually between -1 and+1. But for every type of land cover, there's no distinct boundary.
When you have negative values, for instance, it is highly likely that it is water. Furthermore, if you have an NDVI value similar to +1, there is a strong probability that it will be dense green leaves. But when NDVI is near to zero, green leaves don't exist, and it may even be an urbanized area.
NDVI is the most common index of remote sensing used by analysts. But how do you calculate it? What is NDVI used for?
Keep reading the article for the answers.
How do you calculate NDVI?
Live green plants absorb solar radiation, used as a source of energy during the photosynthesis process.
Leaf cells emit more solar radiation in near-infrared than in visible spectral regions. Live green plants, therefore, appear to be relatively bright in the near-infrared. Chlorophyll on the plant leaves absorbs the visible light (0.4 to 0.7 μm) strongly for photosynthesis.
On the other side, the leaves Extremely's cell structure reflects near-infrared light range from 0.7 to 1.1 μm. The more leaves a plant has, the more influenced are the wavelengths of light.
we can calculate The NDVI According to these individual measurements Using the following NDVI formula:
NDVI = (NIR - VIS) / ( NIR + VIS )
Where VIS and NIR are used for spectral reflectance measurements taken in visible (red) and near-infrared regions, the most efficient way to supply data for NDVI is to provide drone sensors using standard RGB together with infra-red or multi-spectral sensors capturing light in the 600 to 800 nm range.
A farmer can analyze images for NDVI after processing for a variety of crops, plants, or disease indicators. An agronomist can mainly analyze contrasting plant vigor areas and cover large areas of inaccessible land for analysis.
What is NDVI used for?
Many sectors are using NDVI. In agriculture, for instance, farmers use NDVI for precise agriculture and biomass measurement. Simultaneously, Forests use NDVI in the forestry to quantify the supply of forests and the index of leaf areas.
Also, NASA has declared NDVI to be a good drought indicator. When water limits the growth of vegetation, the relative NDVI and vegetation density is lower.
NDVI and other remote sensing applications use in the real world in hundreds of applications.
On the use of drones in Agriculture
The use of drones for agriculture, especially in the field of Precision Agriculture and Farm Management, has developed rapidly over the last five years. UAVs are a groundbreaking tool to obtain information about crop development and thus to improve yields and optimize production efficiency.
UAVs have the unique benefit of enabling a high level of detail to farmland rapid response data. Hundreds of hectares can be covered on only one flight at a reduced cost and a much higher spatial accuracy than human-crewed flights or land surveys.
Photogrammetry software converts the information collected into orthomosaics and 3D models and generates a three-dimensional digital representation of a field's status.
Upon acquiring multi-spectral data, algorithms such as the Normalized Difference Vegetation Index (NDVI) may be applied and become the basis for tracking plant growth and examining crop health.
UAVs carry different sensor modules for various agricultural management applications, including optical, multi-spectral, or thermal modules.
UAV drones are used in various crops and different climates in farming areas all over the world. Farmers, for example, fly UAV drones in the United Kingdom to track the growth of potatoes and improve the use of fertilizers, whereas pineapple fields with the same type of drone are surveyed by world plantation owners in the Philippines to detect plant diseases and improve water drainage. Contact GEOTECH3D for your drone assisted NDVI surveys in UAE and MENA.