Mapping paddy rice yield in Zhejiang Province using MODIS spectral index

Authors : Qian CHENG*, Xiuju WU

Pages : 579-589

View : 10 | Download : 7

Publication Date : 2011-12-01

Article Type : Research Paper

Abstract :The first 19 bands of a moderate-resolution imaging spectrometer insert ignore into journalissuearticles values(MODIS);, covering the visible to shortwave infrared spectral wavelength, were simulated by ground-level reflectance spectra. All spectral indices similar to the normalized difference vegetation index insert ignore into journalissuearticles values(NDVI); and ratio vegetation index insert ignore into journalissuearticles values(RVI); formed by every 2 bands were calculated to obtain their determination coefficients, with theoretical and real yield. Results revealed that the combinative near-infrared insert ignore into journalissuearticles values(NIR); index insert ignore into journalissuearticles values(band 2 and band 19, symbol b2 and b19, and other similar ones); and the insert ignore into journalissuearticles values(b16, b19); of MODIS were strongly correlated with rice yield, especially the correlative coefficient that exceeded significant levels in the maturing stage. However, combinative visible light index was correlated with rice yield strongly in the early stage and poorly in the latter stage. The best spectral indices for predicting rice yield in whole rice growth were the combinations of insert ignore into journalissuearticles values(b2, b19); and insert ignore into journalissuearticles values(b16, b19);. Based on the 2-band combination of the insert ignore into journalissuearticles values(b2, b19); of MODIS and the constructed estimating model, the rice yield of Zhejiang Province was estimated and its spatial distribution was mapped. Estimated results based on MODIS images were validated using 8 measured validation sites. Errors in the estimated rice yield ranged from 3.2% to 20.3%, with a mean value of 10.1%. The results indicated that the 2-band combination of the insert ignore into journalissuearticles values(b2, b19); MODIS index was most suitable for monitoring rice yield.
Keywords : Key words Estimation, rice yield, MODIS, spectral index