Soil-adjusted power comparison and application conditions of vegetation indices based on PROSAIL model

Abstract

Soil-adjusted Vegetation Indexes (SAVIs) have been developed to eliminate the effect of soil background on Vegetation Indices (Vis). The soil-adjusted power of Vis varies with environment conditions. After summarizing the development of SAVI family, we compared and evaluated NDVI, SAVI, TSAVI, MSAVI, OSAVI, and GESAVI in terms of their resistance to soil variations over a series of Leaf Area Indices (LAI). Two datasets in use were simulated through PROSAIL model. The optimal application conditions of these Vis were noted. Based on the signal-to-noise ratio, these six Vis are classified into three categories. OSAVI and TSAVI can adjust soil noise betterly when applied to uniformly distributed canopy with intermediate-low LAI. MSAVI is more stable in the expression of vegetation information when LAI or vegetation species is heterogeneous. Analysis results based on MODIS-VI and MODIS-LAI products over corresponding canopy preliminarily validates our conclusion.