How do you calculate vegetation index?
How do you calculate vegetation index?
Formula of SAVI vegetation index:
- SAVI = ((NIR – Red) / (NIR + Red + L)) x (1 + L)
- ARVI = (NIR – (2 * Red) + Blue) / (NIR + (2 * Red) + Blue)
- EVI = 2.5 * ((NIR – Red) / ((NIR) + (C1 * Red) – (C2 * Blue) + L))
- GCI = (NIR) / (Green) – 1.
- SIPI = (NIR – Blue) / (NIR – Red)
- NBR = (NIR – SWIR) / (NIR + SWIR)
What is vegetation indices in remote sensing?
A Vegetation Index (VI) is a spectral transformation of two or more bands designed to enhance the contribution of vegetation properties and allow reliable spatial and temporal inter-comparisons of terrestrial photosynthetic activity and canopy structural variations.
How many vegetation indices are there?
27 vegetation indices
ENVI provides 27 vegetation indices to use to detect the presence and relative abundance of pigments, water, and carbon as expressed in the solar-reflected optical spectrum (400 nm to 2500 nm).
What is transformed vegetation index?
Transformed Vegetation Index: A commonly used vegetation index derived from images of certain spectral bands. The TVI is equal to the square root of the quotient of the photo-infrared minus the red band, and the photo-infrared plus the red band {SQRT[(IR – red) / (IR + red)]}.
What is chlorophyll vegetation index?
GCI (Green Chlorophyll Index) is used to estimate leaf chlorophyll content in the plants based on near-infrared and green bands. In general, the chlorophyll value directly reflects the vegetation. The GCI formula looks like GCI = NIR / Green – 1.
What are vegetation indices used for?
Vegetation indices are designed to maximize sensitivity to the vegetation characteristics while minimizing confounding factors such as soil background reflectance, directional, or atmospheric effects.
What is vegetation condition?
The Vegetation Condition Index (VCI) compares the current NDVI to the range of values observed in the same period in previous years. The VCI is expressed in % and gives an idea where the observed value is situated between the extreme values (minimum and maximum) in the previous years.
What is the best vegetation index?
NDVI
Normalized Difference Vegetation Index (NDVI) is the most commonly used index, due to its versatility and reliability in reporting general biomass.
What is the vegetation index?
| Index | Formula |
|---|---|
| Red-edge normalized difference vegetation index | R 750 − R 705 R 705 + R 750 |
| Red-edge position index | ( 705 + 35 ) [ ( ( R 783 − R 665 ) / 2 ) − R 705 R 740 − R 705 ] |
| REP for hyperspectral and fused images | Eqs. (19.2) and (19.3) |
| Anthocyanin reflectance index 2 | R 800 ( 1 R 550 − 1 R 700 ) |
How is enhanced vegetation index calculated?
These enhancements allow for index calculation as a ratio between the R and NIR values, while reducing the background noise, atmospheric noise, and saturation in most cases. In Landsat 4-7, EVI = 2.5 * ((Band 4 – Band 3) / (Band 4 + 6 * Band 3 – 7.5 * Band 1 + 1)).
What is VCI index?
What is the enhanced vegetation index (EVI)?
The Enhanced Vegetation Index was invented by Liu and Huete to simultaneously correct NDVI results for atmospheric influences and soil background signals, especially in areas of dense canopy. The value range for EVI is -1 to 1, and for healthy vegetation it varies between 0.2 and 0.8.
What are Vegetation Indices (VIs)?
Vegetation Indices (VIs) obtained from remote sensing based canopies are quite simple and effective algorithms for quantitative and qualitative evaluations of vegetation cover, vigor, and growth dynamics, among other applications.
How do you calculate Savi vegetation index?
Formula of SAVI vegetation index: SAVI = ((NIR – Red) / (NIR + Red + L)) x (1 + L) Key fact: L is a variable. Its values range within -1 to 1, depending on the amount of green vegetation present in the area.
What is the atmospherically resistant vegetation index (ARI)?
As the name suggests, the Atmospherically Resistant Vegetation Index is the first vegetation index, which is notrelatively prone to atmospheric factors (such as aerosol).
