Journal of Aquatic Plant Management
The Aquatic Plant Management Society
APMS Home Page Volume 41 Table of Contents

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Volume

41, 2003

Issue

2

Page

93

 

 

Title

Using Spatial Information Technologies to Detect and Map Waterhyacinth and Hydrilla Infestations in the Lower Rio Grande

 

 

Author(s)

J. H. Everitt, M. A. Alaniz, and M. R. Davis

 

 

Keywords

aerial videography, aerial photography, Eichhornia crassipes, Hydrilla verticillata, global positioning system, geographic information system

 

 

Abstract

This paper describes a study conducted in 2002 on the application of aerial photography and videography, global positioning system, and geographic information system technologies for detecting and mapping waterhyacinth [Eichhornia crassipes (Mart.) Solms] and hydrilla [Hydrilla verticillata (L. F.) Royle] infestations in the Rio Grande in extreme southern Texas. Waterhyacinth and hydrilla could be readily distinguished in color-infrared photography, color-infrared videography, and normal color videography. The integration of the global positioning system with the video imagery permitted latitude-longitude coordinates of waterhyacinth and hydrilla infestations to be recorded on each image. The global positioning system coordinates were entered into a geographic information system to map waterhyacinth and hydrilla infestations in the Rio Grande. This survey showed an increase in distribution of these weeds of approximately 115 river-km within two counties, as compared to a 1998 survey.