Cordilleran Section - 108th Annual Meeting (29–31 March 2012)

Paper No. 1
Presentation Time: 08:30-18:30

UTILITY OF GEOEYE IN ASSESSING RIPARIAN VEGETATION ALONG THE RIO CONCHOS, MEXICO


GUTIERREZ, Melida, Geography, Geology and Planning, Missouri State University, 901 S. National Ave, Springfield, MO 65897, MICKUS, Kevin L., Geology, Missouri State University, Springfield, MO 65897 and JOHNSON, Elias, Geography, Geology and Planning, Missouri State University, 901 S National Ave, Springfield, MO 65897, EliasJohnson@MissouriState.edu

Riparian vegetation helps filter contaminants from runoff discharging into rivers. An impacted river in northern Mexico, Rio Conchos, was used in this study. Multi-spectral high spatial resolution remote sensing has proven very useful in delineating various types of riparian vegetation (Akasheh, 2008). Although GeoEye satellite imagery is limited to four spectral bands and a panchromatic band, its high spatial resolution appears to be more beneficial as a tool in riparian vegetation assessment than the higher spectral resolution of Landsat TM. Beside potential individual species and/or composition recognition and canopy assessment based on textural information, indices that measure chlorophyll can be obtained via use of the near infrared band. However, GeoEye does not have mid-infrared sensors and is limited in its measurement of turgidity of vegetation (Jensen, 2007). The purpose of this research is to show the advantage of using high spatial resolution data with lower spectral resolution (GeoEye) as opposed to Landsat TM’s lower spatial resolution with higher spectral resolution which includes mid-infrared sensors for an irrigated and a non-irrigated riparian area for two different growing periods. To assess the utility of Landsat's mid-infrared sensors, a tassel cap transformation was performed on the two scenes. The best results towards vegetative identification and the development of regions of interest for a supervised classification were obtained using Brovey transformations from GeoEye images. The limited ground truth information available presented a particular challenge and was partially overcome by GeoEye's excellent spatial resolution. The results indicate that the riparian vegetation consists mainly of willow and cottonwood. The tamarix identified in between cultivated parcels as ground truth was not identified in riparian areas. From inspection of the Brovey images, the classification of the two scenes appears to represent land cover categories that can be useful in riparian vegetative mapping.