ESTIMATION OF THE LEAF AREA INDEX USING A MODIFIED TRIANGULAR DIFFERENCE VEGETATION INDEX

The Leaf are index (LAI), a key factor in many physiological processes in plants, plays a crucial role in characterizing vegetation. Various vegetation indices (VIs) have been proposed to estimate such an important parameter. Some issues, however, have been found such as low accuracy and poor robustness. In this study, a Modified Triangular Difference Vegetation Index (MTDVI) was proposed by selecting optimal spectral bands on our previously reported TDVI. It was estimated by retrieving the LAI of summer corn and winter wheat. The results showed that the MTDVI was more sensitive than TDVI and some commonly used VIs to the LAIs of summer corn. To show the performance, another MTDVI0 was used to compared the MTDVI, indicating that MTDVI0 had better coefficient of determination (R-2) but larger root mean squire error (RMSE). The study shows that the proposed MTDVI is satisfactory to retrieve the LAI of wheat and corn, and can be also considered for other similar crops.