PARENT SESSION
Poster Session: Tools for Managing Invasive Plants
Thursday, November 6, 2003, 5:00 PM to 6:00 PM
Global Ballroom
Using spatial information technologies for mapping four invasive weeds on the Rio Grande River system of Texas.
Everitt, James*,1, Alaniz, Mario1, Yang, Chenghai1, Davis, Michael1, Deloach, C.2, Mazariegos, Ruben3, 1 USDA-ARS, Integrated Farming and Natural Resources Research, Weslaco, Texas, USA2 USDA-ARS, Temple, Texas, USA3 University of Texas-Pan American, Edinburg, Texas, USA
ABSTRACT- The Rio Grande River is a major source of water for agricultural and municipal uses in Texas and northern Mexico. Water shortages in the Rio Grande have been significantly impacted by the invasion and spread of four invasive weed species: waterhyacinth (Eichhornia crassipes), hydrilla (Hydrilla verticillata), giant reed (Arundo donax) and saltcedar (Tamarix chinensis). Waterhyacinth and hydrilla are aquatic species that occur in the river, whereas giant reed and saltcedar are wetland species that grow adjacent to the river. This paper reports the results of an aerial remote sensing survey conducted in 2002 on the Rio Grande from its mouth near Brownsville in south Texas to near El Paso in west Texas. Aerial photography and videography were acquired simultaneously of the Rio Grande. Color-infrared photography and videography were used to detect waterhyacinth, hydrilla, and giant reed, whereas conventional color photography and videography were used to distinguish saltcedar. The videography was integrated with global positioning system (GPS) and geographic information system (GIS) technologies for detecting and mapping the distribution of the four weed species. Integration of the GPS with the video imagery permitted latitude-longitude coordinates of weed infestations to be recorded on each image. The GPS coordinates on the video scenes depicting waterhyacinth, hydrilla, giant reed, and saltcedar infestations were entered into a GIS. Distribution maps were developed denoting the locations of infestations of these four weeds in or along the Rio Grande.
Key words: rio grande , remote sensing, global positioning system, geographic information system