In order to explore the feasibility of remote sensing estimation of wheat above ground biomass(AGB) based on neural network,field experiments of winter wheat were carried out in Taixing City of Taizhou City,Dafeng district of Yancheng and Shuyang County of Suqian City,Jiangsu Province.By analyzing the correlation between near-infrared band reflectance(REFnir),red band reflectance(REFred),normalized difference vegetation index(NDVI),difference vegetation index(DVI),ratio vegetation index(RVI),soil adjusted vegetation index(SAVI),optimized soil adjusted vegetation index(OSAVI) and winter wheat growth indices(leaf area index and biomass),a winter wheat biomass estimation model based on BP neural network was constructed,and the estimation accuracy was compared with multiple linear regression model.The results showed that REFred,NDVI,RVI,SAVI,OSAVI,leaf area index(LAI) and AGB had a good correlation at jointing stage of winter wheat.Among them,LAI had the highest correlation with AGB,with a correlation coefficient of 0.782; SAVI had the lowest correlation with AGB,with a correlation coefficient of 0.647.The winter wheat biomass estimation model AGBBP established by BP neural network had a coefficient of determination(r) of 0.918,with root mean square error(RMSE) of 582.9 kg·hm-2,and average relative error(ARE) of 18.4%.The r of the winter wheat biomass estimation model AGBRA established by multiple linear regression analysis was 0.784,with the root mean square error of 871.1 kg·hm-2,and the average relative error of 32.6%.Using winter wheat above-ground biomass estimation models AGBBP and AGBRA to estimate AGB at heading stage of winter wheat,the root mean square errors were 1 140.4 and 1 676.7 kg·hm-2,respectively,and the average relative errors were 20.5% and 33.1%,respectively.The comparison between the two models showed that the accuracy of the winter wheat AGBBP estimation model was better than that of the AGBRA model,indicating that using multiple remote sensing spectral indicators combined with LAI modeling could effectively improve the estimation accuracy of winter wheat biomass. |