Between 690 and 750 nm, leaf reflectance rises several-fold — a phenomenon known as the “red edge.” This one edge carries more information about plant condition than the rest of the visible spectrum combined. This article is a placeholder: fill it in with an explanation of the mechanism (the transition from chlorophyll absorption to mesophyll scattering) and application examples.
To fill in
- The physical mechanism: why the edge is so steep.
- Factors that shift the red edge position (nitrogen, stress, species).
- Indices that use the red edge (e.g. NDRE).
- A simple illustrative spectrum chart with the edge marked.
Content in progress.