Winter Wheat Nitrogen Nutrition Diagnosis Based On The UAV Remote Sensing

Precision nitrogen management plays an important role in ensuring food security,improving nitrogen efficiency(NUE)and reducing environmental pollution.The unmanned aerial vehicles remote sensing(UAVRS)provide important support for the the rapid,non-destructive,real-time crop canopy nitrogen nutrition diagnosis in the large area farmland because of its flexibility and real-time.This study has monitored the winter wheat field in Laoling Shandong and diagnose the nitrogen nutrition of it by using UAV carrying Mini-MCA 6 multi-spectral camera.The main work and results are as follows:(1)Processing the remote sensing image data acquired by unmanned aerial vehicle(UAV),and the average accuracy of the mosaic image is 99.3%(2)The vegetation indices(VIs)can accurately estimate aboveground biomass and plant nitrogen uptake of winter wheat in different growth stage(R~2=0.86~0.94;R~2=0.86~0.93).For the plant N concentration,the estimation effect in the earlier growth stage(Feekes 4-7)is generally(R~2=0.56),while the later growth stage(Feekes 8-10)is better than the earlier stage(R~2=0.75~0.89).(3)Using the nitrogen sufficiency index(NSI)to normalized the vegetation indices(VIs),The estimation ability of NSI-VIs for the nitrogen nutritional index(NNI)is better than original VIs both in single and all growth stage.NSI-MNDI and NSI-MCCCI performed best(R~2=0.75~0.89).(4)The indirectly method to estimate the N nutrition index by using the estimated ABG and PNC has the highest precision.However there is no obvious difference between 5methods,and the consistency between the estimated value and the observed value is all above 80%.