Remote sensing is a cost-effective alternative to ground surveys for assessing biomass and vegetation cover in semi-arid rangelands, but NDVI can be unreliable in areas with sparse vegetation or highly reflective soils. Our study compared NDVI and OSAVI estimates to ground survey data in south Texas and found that OSAVI provided more accurate coverage estimates, particularly for herbaceous and woody vegetation. These results suggest OSAVI is a more suitable spectral index for estimating green biomass and vegetative coverage in semi-arid regions.
