Remote sensing has been an important tool in evaluating
ecosystem health and invasive species monitoring, mapping and management. In the early 1800s, several species of Tamarix
were introduced to the United States.
Three of these, all commonly referred to as saltcedar have become “one
of the most threatening invasive species in the United States over the next ten
years” (Wang L. et al., 2012, p.3). The
saltcedar have dominated the basin in the southwestern US and northern Mexico’s
semiarid climate, due to its hardy nature and ability to tolerate the dry
conditions.
Due to the importance of accurately identifying, mapping,
and inventorying this invasive plant, researchers have turned to several different
remote sensing capabilities to determine which offered the best capabilities to
take on this task. In a study by Wang L.
et al., the researchers chose QuickBird, AISA and Landsat TM to determine which
would offer better multiresolution and multiresource remote sensing
imagery.
The study site was located near Candelaria, TX, along the Rio
Grande river, among the many canyons and valleys of this semiarid region. The flora is mostly composed of saltcedar
with some willow mixed in. Researchers
then began composing data from all three image producing methods. Once researchers had their data, they were
able to complete a comprehensive study of the imagery and determine which would
better work for reconnaissance of the invasive species.
QuickBird remote sensing has been used for detecting
invasive species in the past but had been reported to have limitations with
detecting small strands of scattered trees.
Airborne Imaging Spectroradiometer for Applications (ASIA) is known for
its ability to provide data at a very fine resolution, (between 1-4 meters),
but can be quite costly. Landsat TM is
reported to be ideal due to its wide coverage and low cost. Researchers concluded that out of the three,
ASIA outperformed QuickBird in saltcedar identification and achieved high
scores in accuracy. Landsat TM showed similar accuracy to AISA methods, but was
significantly better with computing efficiency.
The ability to use remote sensing in reconnaissance of
threatening invasive species will allow for better potential for mapping, monitoring
and managing a serious problem in the United States. This study outlines the classification accuracy
between each method, allowing for better quality reconnaissance.
Le Wang, José L.
Silván-Cárdenas, Jun Yang & Amy E. Frazier (2012): Invasive Saltcedar
(Tamarisk spp.) Distribution Mapping Using Multiresolution Remote Sensing
Imagery, The Professional Geographer, DOI:10.1080/00330124.2012.679440
https://moodle.southwestern.edu/pluginfile.php/114788/mod_folder/content/0/Wang-2012-RS_InvasiveSaltcedar.pdf?forcedownload=1
Very interesting study! Does the article mention anything about how state/ federal land management agencies apply the data from remote sensing for invasive species management? It would be awesome to utilize this remote sensing strategy to help categorize the invasive plants in the SU Ecolab and monitor their distribution.
ReplyDeleteUnfortunately, state/federal land management agencies application was not mentioned in this study, other then to say that these remote sensing applications have been used to manage invasive species in the past. It would be interesting to see how we could use these applications in the ecolab!
ReplyDeleteI didn't know that invasive species dealt with trees as well. I know that many environmentalists have concerns of repopulating the forests but I never thought it could run the risk of being classified as invasive.
ReplyDeleteThis information could be very helpful in preventive measures. It could be used to save animals, as well as people, and also could be used as a way to get rid of unwanted and harmful plants and species. I'm really interested to see how this data will be used in the future.
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