title: [The Study Based on Rectification of Vegetation Indices with Dust Impact].
abstract: Vegetation indices are the simplest and most effective metric parameters representing the features of vegetation cover and growth condition. This paper used Euonymus japonicas Thunb as a study case and collected 200 leaf samples in 20 locations. Using electronic analytical balance and ASD hyperspectral radiometer with Win FOLIA leaf area meter obtained the data of the amount of dust, spectral information and leaf area. Through comparative analysis between dust and clean leaves, differences of spectral curve and vegetation indices were apparent. Then, combined with dust weight and spectral data, dust correction models-for vegetation indices were built. The analysis results showed that the spectral curve between clean and dust leaves have typical characteristics: blue edge and red edge were at 520 and 705 nm; however, dust influenced leaf reflectance significantly in range of 350-700, 750-1 350, 1 500-1 850, 1 900-2 100 nm wavelength, and had a greater impact on vegetation indices. With dust weight increasing, the linear correlation of dust with NDVI AND PRI was non-significant, but that with NDWI, NDII and CAI was still significant. The verification of correction models showed that coefficient of determination (R2) of NDVI, NDII, CAI and PRI were 0.547, 0.430, 0.653 and 0.96 and their root mean square error (RMSE) was 0.035, 0.020, 0.112 and 0.009 respectively. Furthermore, it showed that applying dust correction models can improve the accuracy of vegetation indices calculation.
authors.forename: Fan-tao
authors.initials: FT
authors.lastname: Chen
authors.forename: Wen-ji
authors.initials: WJ
authors.lastname: Zhao
authors.forename: Xing
authors.initials: X
authors.lastname: Yan