Peer-Review Record
Enhancing the Nitrogen Signals of Rice Canopies across Critical Growth Stages through the Integration of Textural and Spectral Information from Unmanned Aerial Vehicle (UAV) Multispectral Imagery
Remote Sens. 2020, 12(6), 957; https://doi.org/10.3390/rs12060957
by
Hengbiao Zheng 1,2,3,4, Jifeng Ma 1,2,3,4, Meng Zhou 1,2,3,4, Dong Li 1,2,3,4, Xia Yao 1,2,3,4, Weixing Cao 1,2,3,4, Yan Zhu 1,2,3,4,*
and Tao Cheng 1,2,3,4
and Tao Cheng 1,2,3,4Reviewer 1:
Anonymous
Reviewer 2:
Anonymous
Remote Sens. 2020, 12(6), 957; https://doi.org/10.3390/rs12060957
Submission received: 31 December 2019
/
Revised: 10 March 2020
/
Accepted: 13 March 2020
/
Published: 16 March 2020
Round 1
Reviewer 1 Report
In Line 134, “using six flat calibration canvas a [17, 18]”. Please make sure if this sentence ends properly or not. The manuscript did not show what the full English term of LNA is before Line 166. Does LNA mean “leaf nitrogen accumulation per unit ground area”? Please explain in the manuscript. In Table 3, what do “L” and “E” mean? In Section 3.1 and 3.2, the manuscript showed the relationships between N nutrition parameters and spectral indices, texture metrics and texture indices in different ways. I was wondering: Why only NDRE was selected to show the relationship with N nutrition parameters rather than selecting all spectral indices in Figure 2? Such as the representation format in Figure 3. Is it because NDRE the optimal VI? However, CIRE also performed similar as NDRE. How to determine the optimal VI? In Figure 2, why was linear regression used for calibrating PNC and NDRE and nonlinear regression for PNA and NDRE? I suggest explaining the reason in the manuscript. Also in Figure 4, why was linear regression used for calibrating PNC and NDTI(DIS, COR) and nonlinear regression for PNA and NDTI(MEA)? I suggest explaining the reason in the manuscript. In Figure 3, I suggest explaining linear or nonlinear regression was used for calibrating the relationships between N nutrition parameters and texture metrics. In section 3.4, RMSE and RE (relative error) were used for model validation. However the “RE” may be easily confused with “RE band (red edge)” when mentioning multispectral bands. I suggest using other abbreviation for relative error or red edge band. In Table 8, what does LDB mean? Please explain in the manuscript. Concerning the “Directional effect of texture analysis” in section 4.2, although the planting rows showed the same direction in Figure 6, the crops in the real world may not always be grown in the same direction; furthermore, we cannot let the UAVs always fly along the growing direction. Therefore, I thought the discussion about the direction of texture analysis may only be suitable in very specific conditions and hard to meet the third aim “building a universal model” listed in Line 90. Please try to explain the necessity and contribution of concerning the direction of texture analysis for improving N nutrition monitoring.
Author Response
Please check the Word file.
Author Response File: 
Author Response.docx
Reviewer 2 Report
see attached file
Comments for author File: 
Comments.pdf
Author Response
Please check the Word file.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
All the comments had been replied with acceptable correction.
Author Response
Thank you very much for your valuable comments.
Reviewer 2 Report
see attached file
Comments for author File: Comments.pdf
Author Response
Thank you very much for your comments.
Author Response File: Author Response.docx
