Seasonal Contributions of Understory to Forest Reflectance for Six Forest Types in China

Abstract

Understory vegetation has largely affected the accuracy of forest leaf area index (LAI) estimation. This study analyzed the components of overstorey and understory based on the forest reflectance and transmittance (FRT) model for six forest types in China: i.e. a planted fir forest, a mixed fir and pine forest, deciduous broad-leaved forest, evergreen broad-leaved forest, broad-leaved pinus koraiensis forest, and seasonal tropical rainforest. The contributions of understory were varied for different forest types within a year. The contributions of understory for the tropical rainforest and the coniferous and broad-leaved mixed forest were low due to the dense canopy with higher LAI of overstorey. The effect of understory was unneglectable for the whole wavelengths.