Submitted to: American Society for Photogrammetry and Remote Sensing Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: September 19, 2011
Publication Date: N/A
Interpretive Summary: Not required for abstract.
Technical Abstract: We discuss applications of airborne multispectral digital imaging systems, imaging processing techniques, global positioning systems (GPS), and geographic information systems (GIS) for mapping the invasive weeds giant salvinia (Salvinia molesta) and Brazilian pepper (Schinus terebinthifolius) and for monitoring biological control of saltcedar (Tamarix spp.), in Texas. An airborne six-camera multispectral digital video imaging system and an unsupervised image classification approach were used to map the invasive water weed giant salvinia in a bayou in northeast Texas. User’s and producer’s accuracies for the giant salvinia class were 74.6% and 87.2%, respectively. An airborne five-camera multispectral true digital imaging system and a supervised classification image approach were employed for mapping the invasive terrestrial plant Brazilian pepper at a resaca in south Texas. User’s and producer’s accuracies for the Brazilian pepper class were 100% and 84.2%, respectively. During 2010 and 2011 in west Texas, a medium format true digital color camera was integrated with GPS and GIS technologies to monitor biological control of saltcedar with the saltcedar leaf beetle (Diorhabda spp.) and to track beetle movement. Foliage of saltcedar trees with moderate damage caused by beetle and larvae feeding appeared in distinctive orange and brown color tones on the airborne imagery; defoliated trees had dark gray color tones on the imagery. The camera was tethered to a GPS that recorded the coordinates of the center of each frame and saved this information into an exif file. Coordinate information obtained with the GPS was used to derive a map showing the locations of trees damaged by the beetle. Technologies employed in these studies are promising tools that natural resource managers can use now and in the future to map invasive weeds and to monitor biological control of invasive plants.