 Photochemical Reflectance Index

The Photochemical Reflectance Index (PRI) is a vegetation index used to assess the physiological state of plants and their photosynthetic activity. It is particularly useful for monitoring stress in plants, such as drought or nutrient deficiency, and understanding the dynamics of ecosystems. PRI is based on the reflection of light in certain wavelengths, specifically focusing on the relationship between the reflectance in the red edge (around 700 nm) and the reflectance in the green region of the spectrum (approximately 530 nm).