S.alternif.

Spectrum Details

Modality

NIR

Category

vegetation

Material Type

PLANT

Sample ID

Spartina alterniflora near CRMS-0322v06

Collection Locality

Coastwide Reference Monitoring System (CRMS) site 322 near subplot v06. CRMS322v06 is located in southern Louisiana, approximately 127 kilometers southwest of New Orleans, Louisiana, in the western part of the Terrebonne hydrologic basin on the coast of the Gulf of Mexico.

Spectral Purity

1a2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

Sample Description

This spectrum is the average reflectance of 8 field measurements (using an artificial light source) of green leaves and stems of smooth cordgrass (Spartina alterniflora). The measurements were made on June 7, 2010. These spectra were made using an ASD Field Spectrometer 3 (FS3) in reflectance mode, relative to a Spectralon reference panel. The contact probe attachement (an artificial light source with a restricted, 1 cm diameter, field of view) was used to measure the reflectance spectra of bundles of leaves and stems.Plant stems and leaves in the top 30 cm of the canopy were bunched together. The contact probe was pressed against the optically thick bundle and a spectrum was recorded at two positions along the length of each bundle. An average spectrum was computed from the recorded measurements. The average spectrum was converted to absolute reflectance by multiplying by the reflectance spectrum of the Spectralon reference panel. The first 50 channels (0.35 - 0.40 microns) in the spectral measurement show relatively high levels of noise. Site Classification The area has been predominantly classified as saline marsh (see http://lacoast.gov/crms2/home.aspx). General Site Description The plot is located in southern Louisiana, approximately 127 kilometers southwest of New Orleans, Louisiana. It is in the western part of the Terrebonne hydrologic basin on the coast of the Gulf of Mexico. For additional information on the CRMS site see http://lacoast.gov/crms2/home.aspx Project Background This site was measured as part of joint work between the USGS Denver Spectroscopy Laboratory and the Coastal Restoration Assessment Branch of the USGS National Wetlands Research Center, Baton Rouge. This spectrum was used in: Kokaly, R.F., Couvillion, B.R., Holloway, J.M., Roberts, D.A., Ustin, S.L., Peterson, S.H., Khanna, S., and Piazza, S.C., 2013, Spectroscopic remote sensing of the distribution and persistence of oil from the Deepwater Horizon spill in Barataria Bay marshes, Remote Sensing of Environment, Volume 129, Pages 210-230. http://dx.doi.org/10.1016/j.rse.2012.10.028 IMAGE_OF_SAMPLE: subplot location corresponds to the number within the parantheses in the site layout diagram

X Units

cm⁻¹

Y Units

Absorbance

Data Points

2,126