NDVI (Normalized Difference Vegetation Index) USING ARCGIS

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NDVI (Normalized Difference Vegetation Index) is a numerical indicator used in remote sensing and geographic information systems (GIS) to assess the health and density of vegetation cover in a given area. It is calculated from the reflectance of visible and near-infrared light captured by satellite or aerial imagery. Here's a brief description of NDVI:

Calculation: NDVI is calculated using the following formula:

                                           

where NIR represents near-infrared reflectance and Red represents red light reflectance.

Values: NDVI values typically range from -1 to 1. 

        The interpretation of NDVI values is as follows:

  • Values close to -1: These indicate non-vegetated surfaces, such as water bodies or barren land.
  • Values around 0: These usually represent built-up areas or areas with no live vegetation.
  • Values between 0 and 1: These indicate the presence of vegetation, with higher values signifying healthier and denser vegetation.

Applications: NDVI is a fundamental tool in various fields, including agriculture, forestry, ecology, and land management. It is used to monitor changes in land cover, detect vegetation stress, assess crop health, estimate biomass, and track environmental changes over time.

Mapping: In practice, NDVI values are often depicted on maps using a color scale, where low values are displayed in cooler colors (e.g., blue), and high values are shown in warmer colors (e.g., green). This helps in visualizing and interpreting the distribution of vegetation cover in a given area.

NDVI is a valuable metric for understanding and monitoring the state of vegetation in both natural and managed landscapes, and it provides critical information for decision-making in various environmental and agricultural applications.

The below map shows the NDVI of serampore tehsil of Hoogly District of year 2013.




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