Forest Management Using Remote Sensing
Posted February 1, 1998
Aerial photographs have been used by foresters to make management plans for forests for the last 50 years. Photographs have limitations, however, because they only
measure the light reflected from objects on the ground. The wavelengths of light that can be detected by photographic film range from ultraviolet light to a few wavelengths of infrared
light. Remote sensing satellites, on the other hand, can collect data from a greater range of wavelengths, beginning with visible blue light all the way to the thermal infrared portion
of the light spectrum. Each of the wavelengths of light can provide data that enable foresters to determine the species, numbers, and density of trees in a forest.
Why is it necessary to identify the species, numbers, and density of trees in a forest? In order to effectively manage a forest it is important to determine how many
different species there are and how these specie groups are distributed throughout the forest. For example, if one of the goals in managing a forest is to ensure protection of the endangered
pine warbler, it would be important to know the sizes and exact locations of pine stands within that forest. If pine trees are being cut for timber, it would be important to know the
elevation, slope, and soil type in order to predict areas where new pine seedlings should be planted. Satellite data also enables forest managers to monitor the spread of insects and
disease.
To determine how effective the data from satellite remote sensing is in enabling forest managers to find pine stands in forests that are primarily hardwood, satellite
data and aerial photographs of the Hoosier National Forest in Indiana were compared. The overall agreement of results of the comparative study was 76 percent, which the researchers considered
quite good. Researchers point out that good forest management should include the study of both satellite imaging and aerial photography.
References
Johnston, Jerry J., Dale R. Weigel, and J.C. Randolph. "Satellite Remote Sensing - An Inexpensive Tool for Pine Plantation Management." Journal of Forestry,
June 12, 1997, pp. 16-20.
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