关键词: 荒漠植被, 高光谱, 多光谱, 植被指数, 干旱区

Abstract: The spectral discrimination of typical vegetation in the Tarim river basin and the effect of background were analyzed in the paper. Firstly, an ASD Spectral Measurement Instrument was used to measure the fresh leaf reflectance, by which the spectral characteristic points were determined. Then we simulated the EO-1 hyperion spectra and TM spectra with leaf spectrum. Finally, the spectra of vegetation and soil were linear mixed. In these three processes the vegetation indices were calculated. Results showed that vegetation may be discriminated by leaf spectral characteristic positions, which including blue band 430 nm, red band 670 nm, near infrared 750 nm, yellow edge gradient, infrared platform mean height, water absorb band 1 080~1 280 nm and 1 430~1 650 nm. The simulated EO-1 spectra kept the ten features of controlling spectral shape in leaf, on the contrary, the simulated TM only retained the green reflective peak, red absorb hollow and near infrared reflective peak, most of features disappeared. Vegetation indices demonstrated that (R68-R500)/R750, (R680-R550)/R705, R1430+\:+R1650, D712/D688 may be different vegetation forms in the Tarim river basin, which are combination of green peak, red hollow and near infrared.

Key words: desert vegetation, hyperspectral, multispectral, vegetation indices, arid region