Tree height is an essential ecological trait, as the competition for sunlight determines which trees flourish and which become suppressed and eventually die out. It also influences shade in streams, changes in understory vegetation over time, and cover for wildlife. It is an integral part of many natural resource data collection projects.
Side by side comparison of a True Color Image and False Color Image of Melbourne City, Australia.
Red areas in the False color image indicate vegetated areas.
We can determine tree heights using a Canopy Height model. They are derived from Digital Surface Models (DSMs) and Digital Terrain Models (DTMs) over forested and highly vegetated areas. From our previous blog posting “A Detailed Primer on Digital Elevation Models”, DSMs and DTMs are spatial datasets that represent the relief of a surface between points with known elevation. It represents the 3-dimensional values of a terrain’s surface.
Canopy height models are calculated by comparing the difference between the digital terrain model (DTM) from the digital surface model (DSM) over vegetation or forested areas.
Canopy height applications can help government agencies, companies, non-profit organizations, and other related institutions by supplying accurate and spatially explicit high-resolution tree canopy height data for performing a wide range of mapping and spatial analysis functions. These applications include but are not limited to:
- Assessing vegetation risk to power lines and other utility infrastructure
- modeling of forest metrics like tree size class, basal area, volume etc., in conjunction with suitable field data
- assessing forest fuel load and fire risk
- monitoring logging and forest recovery
- evaluating the condition of forests in recreational and protected areas
- improving line of sight radio wave propagation modeling for telecommunications and wireless communications
- assessing habitat suitability for wildlife
- creating and analyzing forest inventory
- assessing accurate visibility in forested regions from ground surface points
- identifying locations of trees that may qualify for inclusion in a Big Tree Register
If a canopy height model would add insights to your organization, reach out to Proimagery today!