Skip to main content

Deforestation

Monitoring protected forest areas for unauthorized clearing, especially in remote regions where ground patrols are infeasible.

Sensor: multispectral (visible + NIR).

Pipeline:

  • Collect: multispectral image over protected forest AOI.
  • Map: compute NDVI per pixel: NDVI=NIR−RedNIR+Red\text{NDVI} = \frac{\text{NIR} - \text{Red}}{\text{NIR} + \text{Red}} Compare against baseline NDVI map. Flag pixels where Δ\DeltaNDVI exceeds deforestation threshold (e.g. drop of > 0.3).
  • Reduce: cluster changed pixels, compute area in hectares. Filter out seasonal variation using baseline update schedule. Generate alert if cleared area exceeds minimum (e.g. > 1 ha).

Alert payload: ~3 KB (polygon outline of cleared area, area in hectares, NDVI delta, timestamp).

Feasibility:

  • NDVI computation is trivial (2 bands, 1 division per pixel).
  • Cloud cover is the main limitation; SAR-based alternatives (backscatter change detection) work through clouds but require more complex processing.
  • Baseline must be updated seasonally to avoid false alerts from natural phenology changes.