Estimating Agricultural Cropping Intensity Using a New Temporal Mixture Analysis Method from Time Series MODIS

Round 1

Reviewer 1 Report

The manuscript mainly deals with the relevant issue of estimating agricultural cropping intensity by a new method using time-series MODIS data. The MODIS image has the promise to monitor crop cropping intensity. The author draws some satisfactory conclusions. However, I thought there are still several problems with this manuscript.

 

1.      Line 57-66: The authors explained the shortcomings of MODIS images and introduce the Sentinel-2, However, following part, the author will also use MODIS. This is confusing and illogical.

2.      Most maps are irregular, without latitude, longitude, and North Arrow.

3.      Figure 3: What do the different color bars of figures b, c, and d represent? please explain it in the figure or title.

4.      Line 242: change “identifying” to “identify”.

5.      Figure 6: please add the correct “Legend”. Cropping intensity (CI)?

6.      Figure 8: Where are A and B? What are the c and d?

7.      From line 325 to the end, please check the order of all figures. For example, Line 325-326, Figure 1 is incorrect.

8.      I thought the authors should add the RMSE in the figures for the scatter plot.

9.       Line 344 and 351: Table 2 is correct.

10.  Line 403: delete this sentence.

Author Response

The manuscript mainly deals with the relevant issue of estimating agricultural cropping intensity by a new method using time-series MODIS data. The MODIS image has the promise to monitor crop cropping intensity. The author draws some satisfactory conclusions. However, I thought there are still several problems with this manuscript.

1. Line 57-66: The authors explained the shortcomings of MODIS images and introduce the Sentinel-2, However, following part, the author will also use MODIS. This is confusing and illogical.

Answer: It’s not shortcomings of MODIS images, but of the existing methods of cropping intensity mapping (CF). CF is a nominal measurement and lack quantitative measurement of cropping intensity. The previous a few sentences have explained this point.

 

2. Most maps are irregular, without latitude, longitude, and North Arrow.

Answer: We have redrawn all these maps by placing necessary map elements.

 

3. Figure 3: What do the different color bars of figures b, c, and d represent? please explain it in the figure or title.

Answer: It represents the value ranges of the three principal components and has been added to the legend.

 

4. Line 242: change “identifying” to “identify”.

Answers: We 've corrected the spelling error.

 

5. Figure 6: please add the correct “Legend”. Cropping intensity (CI)?

Answers: Yes, it should be “CI” and has been corrected.

 

6. Figure 8: Where are A and B? What are the c and d?

Answers: A and B refer to the two test areas, and c and d are ISODATA classification results. We have corrected these confusions

 

7. From line 325 to the end, please check the order of all figures. For example, Line 325-326, Figure 1 is incorrect.

Answers: The numerical orders of the figures have been corrected, thanks for the comments.

 

8. I thought the authors should add the RMSE in the figures for the scatter plot.

Answers: The RMSE has been added to the Figures.

 

9. Line 344 and 351: Table 2 is correct.

Answers: We have corrected this error.

 

10. Line 403: delete this sentence.

Answers: We have deleted the redundant sentence.

 

 

Author Response File: Author Response.docx

Reviewer 2 Report

Dear authors, 

Congratulations on the very nice work. The manuscript addresses an important topic, to which only a few authors have been dedicating some time and effort to advance this field. The idea of the work is great. However, there are some issues related to the organization of the information in the manuscript. I included all my suggestions in the pdf version.

Comments for author File: Comments.pdf

Dear authors,

There are some situations in the text were some words and phrases were without context. I highlighted some of them. However, I would recommend and detailed review of the English just to be sure of solving these issues.

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

ReviewL

The manuscript is interesting and well written.

Minor corrections needed:

Figure 1, change order of k50SKG and 49RFP, as these are in different order in all other figures.

Line 192, DOYà first time used Day of year (DOY)

Line 220, ENVI, the use of this software could be mentioned in the Methods and Data part.

Line 274, consist à correlates

Figure 7, A and B are two test regionsà A and B not shown in maps.

Figure 8, same comment

Line 326 à wrong figure number, should be 9

Line 334 -> wrong figure number, should be 10

Line 338, reasonability à validity

Line 341 à two-dimensional or three-dimensional as in figure 11

Figure 11, it is difficult to distinguish the colors in the legend

Line 405-407 : The method is only suitable for North ……. This needs some clarification, because usually we are searching for universally applicable methods. Why is it only applicable to the test area?

Line 419, wrong figure number, should be 15.

 

 

 

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 4 Report

It is very interesting article. But it must be meantioned the following related issues.

State of the art consists form a lot of old papers (1974, 1993, 1998, 2010) and local publications. It woud be good to refine this part and provided more fresh and systematic modern material at global scale.

Some reference data are based on Sentinel-2 data. Is it right that authors used validation datasets generated without any grounf truth data? If any, it should be described properly in detail. 

Fig. 7 is needed to be described in more details. It is not very clear and authors didn’t provide any qualitative estimations of accuracy.

Validation was done mainly visually (as authors said) and on the basis of S-2 data. All the procedure is unclear, especially using ground truth data. It should be significantly improved.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Congratulations to the authors for providing this new version. I have no specific comments at this moment.p

Author Response

Thank you for your comments.