Hyperspectral remote sensing estimation models on vegetation coverage of natural grassland
Liu, Z.; Huang, J.; Wu, X.; Dong, Y.; Wang, F.; Liu, P.
Ying Yong Sheng Tai Xue Bao 17(6): 997-1002
2006
ISSN/ISBN: 1001-9332 PMID: 16964930 Document Number: 599221
By using ASD FieldSpec Pro FRTM spectroradiometer, the spectral measurement of natural grassland in Xilingole Leaguer of Inner Mongolia was performed, with the vegetation coverage of natural grassland calculated, and the correlation of 25 hyperspectral feature variables with the vegetation coverage of natural grassland was analyzed. The results showed that there were 17 variables correlated significantly with the vegetation coverage of natural grassland, among which, the correlation coefficient between vegetation coverage and the area of red edge peak calculated as the sum of the amplitudes between 680 nm and 780 nm (Sigma dr 680 similar to 780 nm) was the highest, with the value of 0.781. The basic experimental data including the vegetation coverage and canopy reflectance of natural grassland were classified into two groups. One group was used as the training sample to build the regression models with one-sample linear method, nordinear method, and stepwise analysis method, while the other was used as the testing sample to test the precision of regression models. It was suggested that the variable of the area of red edge peak calculated as the sum of amplitudes between 680 nm and 780 nm (Sigma dr 680 similar to 780 nm) was the best one to univariate general linear model, with a standard deviation of 10.4% and an estimation precision of 83.99%, while the stepwise regression technique was not effective to estimate the grassland coverage with raw hyperspectral canopy reflectance.