The use of NOAA-AVHRR NDVI data to assess herbage production in the arid rangelands of Central Australia

Abstract

NOAA-AVHRR data are examined for their potential application in assessing primary productivity in the arid rangelands of Central Australia. Field measurements of herbage biomass are correlated with four indices derived from NOAA-II Normalized Difference Vegetation Index (NDVI) data. Pre-flight and sensor degradation calibrations of bands 1 and 2 and atmospheric correction techniques are also tested. Regional herbage production can be readily estimated using backgroundadjusted maximum NDVI values for a growth season, with NDVI data derived from sensor degradation calibrations of bands 1 and 2 and corrected for atmospheric effects by band 4– band 5 temperature differences (T₄ – T₅,). Correlations between temporal sums of NDVI and herbage biomass data are relatively poor and unsuitable for herbage assessment in Central Australia.