A vegetation index — 0 compatible sensors — Last revised June 1, 2025
PSRI
Plant Senescence Reflectance Index
An index used to detect changes in plant pigmentation during leaf senescence and development. Helps researchers understand plant pigment changes and vegetation health across different species and developmental stages.
Used in crop monitoring.
When to use
- Time-series monitoring of crop health, growth stages, and stress detection
- Land cover classification and vegetation type discrimination
- Biomass estimation and net primary productivity studies
- Drought impact assessment over agricultural and forest areas
- Phenology tracking — green-up, peak season, and senescence
- Vegetation analysis
- Plant senescence detection
Limitations
- Saturates in dense canopies (LAI > 3) — values plateau and lose discrimination ability
- Sensitive to atmospheric scattering, especially blue-band haze
- Soil background contaminates measurements in sparsely vegetated areas
- Sun-sensor geometry (BRDF effects) introduces variability across acquisitions
- Cloud cover and shadows produce invalid pixels that need masking
What the values mean
-1 Water / Snow
-0.1 Bare ground / Built-up
0.1 Sparse / Stressed
0.3 Moderate vegetation
0.5 Healthy vegetation
0.7 Dense canopy
| Surface type | Typical PSRI |
|---|---|
| Open water, snow | -0.3 to -0.1 |
| Bare soil, urban | -0.1 to 0.2 |
| Sparse or stressed crops | 0.2 to 0.4 |
| Healthy crops, grassland | 0.4 to 0.7 |
| Dense forest, peak season | 0.7 to 0.9 |
General Formula
Sensor-Specific Formulas
Most-used sensors — click to show code below
| Sensor | Provider | Formula | Band Mapping |
|---|
Code Examples
psri_generic.py
PSRI vs other vegetation indices
| Index | Name | How it differs |
|---|---|---|
| ARI | Anthocyanin Reflectance Index | Alternative vegetation index — different band combination |
| mARI | Modified Anthocyanin Reflectance Index | Refined formulation for specific conditions |
| ARVI | Atmospherically Resistant Vegetation Index | Atmospherically corrected version |
| ARVI2 | Atmospherically Resistant Vegetation Index 2 | Atmospherically corrected version |
Related Vegetation Indices
ARI
Anthocyanin Reflectance Index
mARI
Modified Anthocyanin Reflectance Index
ARVI
Atmospherically Resistant Vegetation Index
ARVI2
Atmospherically Resistant Vegetation Index 2
BGI
Blue Green Pigment Index
BNDVI
Blue Normalized Difference Vegetation Index
bNIRv
Blue Near-Infrared Reflectance of Vegetation
BRI
Blue Red Pigment Index
References
Apan et al. (2003)
Merzlyak et al. (1999)
Sims & Gamon (2002)
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