Wetland vegetation reflectance variability for species level classification of hyperspectral data

Francisco Artigas.
Meadowlands Environmental Research Institute, Rutgers University.
artigas@cimic.rutgers.edu

A study was conducted to investigate whether reflectance data from Phragmites australis and Spartina alterniflora in a New Jersey wetland could be used for species level discrimination using hyperspectral remote sensing images. Fall reflectance spectra for both species were collected in the field using a field spectroradiometer for high and low elevation marsh and for different vegetation cover types. An analysis of inter and intra species spectral shape was performed to determine the roll of plant structure and percent vegetation cover in the variability of the spectral response. Future work will attempt to determine which filters derived from the spectral shapes best discriminate Phragmites sp. form Spartina sp. in a hyperspectral image.

Marsh wetland vegetation at River Bend, Hackensack Meadolands District.

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AISA sensor false color composit of wetland vegetation bands 3, 15 and 28 (center bands at 525.8, 652.23 and
807.2 nm) flown October 11th. 2000, at 11:30 AM. The low lying area (left of image) shows marsh vegetation. Bright red is mainly Phragmites australis, darker green-grey colors are wet tidal ponds with Spartina alterniflora. Yellowish stands are Spartina patens and Distichlis spicata stands..

Marsh vegetation of the Saw mill Creek wildlife
management area.

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AISA sensor false color composit of wetland vegetation bands 3, 15 and 28 (center bands at 525.8, 652.23 and 807.2 nm) flown October 11th. 2000, at 11:30 AM.
The right side of  Saw mill creek peninsula is dominated by Phragmites australis (red color). Within the Phragmites there are grey-green spots which are low elevation tidal ponds. Left of the peninsula are low laying areas with exposed sediments at low tide and stands of Spartina alterniflora.

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Spectral response for three wetland species: Phragmites australis, Spartina alterniflora and Spartina patens. The curves are means of three hundred samples for each species under bright sun conditions.