Analysis of spectral difference feature parameters of Cynanchum komaroviii

Cynanchum komarovii is one of the main poisonous weed distributed in arid and semi-arid desert steppes of northwest china. In recent years, rapid spreading of C. komarovii has brought serious harm to local animal husbandry and grassland productivity. With field measured spectra of C. komarovii and other psammophyte plants acquired in the typical district of Alxa Left Banner, Inner Mongolia, spectral characteristics of leaf, canopy and community were compared to discuss the differences between C. komarovii and other psammophyte plants. The results showed that the reflectance of C. komarovii leaf was higher than that of the flower in 350-2 500 nm and the flower spectra did not appear obvious blue valley and green peak. Sand background has strong influence on the canopy spectra of C. komarovii, which was the combination of the leaf and sand. The main spectral differences between canopy spectra of C. komarovii and other psammophyte plants were the largest red edge slope and obvious high reflectance in 800-1 300 nm. According to spectra changes of C. komarovii communities with different coverage, 4 feature parameters were selected to analysis the linear regression between parameters and community coverage which showed red edge slope had the best result (R2=0.781 5). This study provides scientific basis for monitoring and retrievaling coverage of C. komarovii using remote sensing techniques.