linear array technology. Since the width and
positioning of each band (up to 288
simultaneously) is programmable and can be
changed inflight to reflect localized conditions (e.g.
forest type or insect or disease damage)
application-specific data can be acquired in a more
efficient and cost-effective manner. The software
programmability of these systems make them
compatible with the use of expert systems. An
inflight expert system could evaluate the spectral
signature over a given area and by comparing
with existing spectral libraries and other expert
knowledge, determine optimal band width and
positioning and the flying height required to
optimize data collection over a site.
Ideally, any new developments in airborne
linear array technology would incorporate the
operationally capability of the MEIS system with
the flexible programmability of the FLI and CASI
systems. This would provide a truly operational
system which could indeed function as a viable
alternative to conventional aerial photography.
5.2 Recommendations
General:
Research has shown a tremendous
potential for applications of linear array imager
data to assist in forest inventory and management.
The requirements for additional research can be
categorized as:
1) immediate research to prove the
operational feasibility of existing and
proposed airborne linear array systems for
forestry applications,
2) research to develop immediate applications
(this includes study through the pilot
stage into an operational stage),
3) long term applications research (this would
include development of automated
techniques), and
4) development of the methodologies, software
and hardware to conduct processing and
undertake applications in an efficient, cost-
effective manner.
Specific:
1) Operational testing is required to evaluate
the types of forestry-related information
that can be obtained from available linear
array systems (e.g. MEIS, FLI and CASI).
2) The capability of stereo airborne linear
array imagery for stand height
measurements and terrain correction
requires further investigation.
3) Inexpensive imaging spectrometers (e.g.
CASI) need to be investigated as a means
of establishing signature libraries for
forest covers and for determining optimal
wavelengths for special forestry
applications (e.g. disease and insect
damage assessment).
4) The feasibility of integrating airborne
linear array data into existing geo-
referenced forest inventory databases need
to be examined. This would require an
examination of available processing
systems for airborne digital data (e.g. the
ability to mosaic images to obtain large
area coverage) and interfaces to computer-
based geographic information systems.
6.0 REFERENCES
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Stress on Foliar Spectral Reflectance of
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Ahem, FJ., W.J. Bennett, and E.G. Kettela, 1986.
An Initial Evaluation of Two Digital
Airborne Imagers for Surveying Spruce
Budworm Defoliation, Photogrammetric
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Ahem, FJ., W.J. Bennett, and E.G. Kettela, 1985.
Surveying Spruce Budworm Defoliation
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