Water Stewardship Information Sources

Citation Leckie, DG et al. 2005. Automated mapping of stream features with high-resolution multispectral imagery: An example of the capabilities. Photogrammetric Engineering & Remote Sensing 71:141-155.
Organization NRCAN
URL http://www.cfs.nrcan.gc.ca/pubwarehouse/pdfs/25174.pdf
Abstract/Description or Keywords The capabilities of high-resolution, multispectral remote
sensing imagery to map important stream features is investigated.
Eighty centimeter spatial resolution CASI imagery was
acquired in eight spectral bands over Tofino Creek on the
west coast of Vancouver Island, British Columbia. A spectral
angle mapping algorithm was used to classify stream habitat
including hydraulic habitat, substrate material, and woody
debris. Subclasses were attempted in terms of streambed
material and water depth, but results were not reliable. A
classification of deep water, moderate depth water, shallow
water, sand, gravel and cobble, and woody debris in sunlit
conditions, however, proved accurate (80 percent on average).
Individual logs and piles of woody debris were consistently
detected. Silty substrate in a tidal flats zone was also
classified, but results indicated that different substrate material
beneath the water may require separate classes and can
result in problematic water depth classification. Patterns of
general classes were reasonably represented within shadowed
areas cast by isolated trees or groups of trees. However,
problems do arise within lengthy shadowed stretches. Some
boundaries of stream features with surrounding forest and
between some zones of sand, gravel, and cobble were also
misclassified. High-resolution, multispectral imagery in four
or more bands combined with good geometric correction,
image mosaicking, and appropriate automatic classification
techniques offer a viable tool for stream mapping to meet a
variety of issues and applications. In the future, a powerful
suite of stream information may be compiled from multispectral
classification combined with high-resolution thermal and
lidar data.
Information Type Article
Regional Watershed Vancouver Island North
Sub-watershed if known Tofino Creek
Aquifer #
Comments
Project status complete
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