Estimation of grassland biophysical parameters in a “dehesa” ecosystem from field spectroscopy and airborne hyperspectral imagery


  • J.R. Melendo-Vega Consejo Superior de Investigaciones Científicas (CSIC)
  • M.P. Martín Consejo Superior de Investigaciones Científicas (CSIC)
  • L. Vilar del Hoyo Consejo Superior de Investigaciones Científicas (CSIC)
  • J. Pacheco-Labrador Consejo Superior de Investigaciones Científicas (CSIC)
  • P. Echavarría Consejo Superior de Investigaciones Científicas (CSIC)
  • J. Martínez-Vega Consejo Superior de Investigaciones Científicas (CSIC)



field spectroscopy, airborne hyperspectral imagery, biophysical parameters, grassland, CASI, spectral indices


The aim of this paper is the estimation of biophysical vegetation parameters from its optical properties. The variables Fuel Moisture Content (FMC), Canopy Water Content (CWC), Leaf Area Index (LAI), dry matter (Cm) and AboveGround Biomass (AGB) were estimated in the laboratory from vegetation samples collected simultaneously with the acquisition of spectral data from the Compact Airborne Spectrographic Imager (CASI) sensor and the field spectroradiometer ASD FieldSpec® 3. Spectral vegetation indices found in the literature were computed from hyperspectral data. Their linear relationships with the biophysical variables measured in the field were analysed. Results show consistent relationships between analysed biophysical parameters and spectral indices, mainly those using SWIR and red-egde bands which reveal the importance of these spectral regions for the estimation of biophysical variables in herbaceous covers. Determination coefficients (R2) above 0.91 and RRMSE of 21.4% have been obtained for the spectral indexes calculated whit ASD data, and 0.91 R2 and RRMSE of 15.5% for the spectral indexes calculated whit CASI data.


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Author Biographies

J.R. Melendo-Vega, Consejo Superior de Investigaciones Científicas (CSIC)

Laboratorio de Espectro-radiometría y Teledetección Ambiental (SpecLab), Instituto de Economía, Geografía y Demografía

M.P. Martín, Consejo Superior de Investigaciones Científicas (CSIC)

Laboratorio de Espectro-radiometría y Teledetección Ambiental (SpecLab), Instituto de Economía, Geografía y Demografía

L. Vilar del Hoyo, Consejo Superior de Investigaciones Científicas (CSIC)

Laboratorio de Espectro-radiometría y Teledetección Ambiental (SpecLab), Instituto de Economía, Geografía y Demografía

J. Pacheco-Labrador, Consejo Superior de Investigaciones Científicas (CSIC)

Laboratorio de Espectro-radiometría y Teledetección Ambiental (SpecLab), Instituto de Economía, Geografía y Demografía

P. Echavarría, Consejo Superior de Investigaciones Científicas (CSIC)

Laboratorio de Espectro-radiometría y Teledetección Ambiental (SpecLab), Instituto de Economía, Geografía y Demografía

J. Martínez-Vega, Consejo Superior de Investigaciones Científicas (CSIC)

Laboratorio de Espectro-radiometría y Teledetección Ambiental (SpecLab), Instituto de Economía, Geografía y Demografía


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