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Conservation of the vulnerable Vitellaria Paradoxa

on all four spectral bands and the application of these To address potential multicollinearity among variables,
indices are presented in Table 2. the variance inflation factor step function was applied.
All computations and visualizations were performed The ratio vegetation index showed a markedly high
using the raster and terra packages in R programming. correlation (>9.0) with all vegetation indices. While the

Figure 2. Image processing workflow into vegetation indices (dark area = no data). A total of 24 images were
obtained from six scenes of four spectral bands each (6 × 4).
Abbreviations: EVI: Enhanced vegetation index; GNDVI: Green normalized difference vegetation index;
MNDWI: Modified normalized difference water index; NDVI: Normalized difference vegetation index;
NDWI: Normalized difference water index; OLI: Operational Land Imager; SAVI: Soil-adjusted vegetation
index; TIRS: Thermal Infrared Sensor.

Table 2. Vegetation indices’ description and arithmetic computation
Index Description Source Bands Formula Application/uses
NDVI Normalized difference 29 Red, NIR (NIR−red)/(NIR+red) Plant growth, yield
vegetation index
RVI Ratio vegetation index Red, NIR Red/NIR Biomass
GNDVI Green normalized 13 Green, NIR (NIR−green)/(NIR+green) Chlorophyll, plant health,
difference vegetation nitrogen
index
EVI Two-band enhanced 17 Red, NIR G×(NIR−red)/(NIR+2.4×red+1) Biomass, yield
vegetation index
SAVI Soil-adjusted 16 Red, NIR (NIR−red)×(1+L)/(NIR+red+L); Monitoring seed and leaf
vegetation index L=0.50 development
NDWI Normalized difference 30 Green, NIR (Green−NIR)/(Green+NIR) Water bodies detection
water index
MNDWI Modified normalized 31 Green, SWIR2 (Green – SWIR2) / (Green + Improved water stress,
difference water index SWIR2) drought detection
SLAVI Specific leaf area 32 Red, NIR, NIR/(Red+SWIR2) Biomass, canopy cover
vegetation index SWIR2
Abbreviations: NIR: Near infrared; SWIR2: Short-wave infrared 2.

Volume 22 Issue 4 (2025) 93 doi: 10.36922/AJWEP025210160