Quantitative Evaluation of Soil Quality Using Principal Component Analysis: The Case Study of El-Fayoum Depression Egypt

Round 1

Reviewer 1 Report

The research was done correctly in terms of methodology.The results are well described and compared with the current literature.They have innovative elements.They can be published with minor corrections.

Comments

1. The unit "ppm" is non-SI.
2. "mg kg^-1" should be used in place of "ppm", eg, lines 187-188, Table 1, 2, 4, 8.
3. Check the list of references, as not all items have been written correctly, eg item no. 13, 40, 58, 65.
4. Instead of "Km" the unit should be "km", eg Figure 7 and 8.
5. In this type of studies, it is debatable to determine soil pH in water instead of KCl or CaCl₂ solution

Author Response

1. The unit "ppm" is non-SI.

We have checked and modified

 

1. "mg kg^-1" should be used in place of "ppm", eg, lines 187-188, Table 1, 2, 4, 8.

We have considered and changed

 

1. Check the list of references, as not all items have been written correctly, eg item no. 13, 40, 58, 65.

We have checked the reference and changed

1. Instead of "Km" the unit should be "km", eg Figure 7 and 8.

We have considered and changed

 

1. In this type of studies, it is debatable to determine soil pH in water instead of KCl or CaCl₂ solution

 We have measured pH according to stander method

Reviewer 2 Report

Summary:

This manuscript, by Abdel-Fattah et al., attempts to capture soil quality using principal component analysis and map the soil quality index based on date reduction clustering methods. Overall, the topic is of interest to sustainability (MDPI) readers. However, there are some issues that can be immediately addressed to improve the overall impact

 

Broad Comments:

1. Introduction requires more deeper review on need for the study and how different is PCA based data reduction methods different from other models
2. The authors addressed using the model to predict them in unsampled locations. This was not addressed in the results and not even in the conclusion section. Adding more explanation on how the results from this model could be used for predicting soil quality would be useful.
3. How do you address within-sample variability? How many soil samples did you take from each location? Are these 36 locations treated as one experiment?
4. More details on the experiment design and sampling scheme is required. On what basis these 36 locations were chosen? Any underlying assumptions or randomly chosen?

 

Specific Comments:

Ln 15 : “Precision farming” is more standard usage.

Ln 25: 13.89 of what? Variability in data?  

Ln 43-48: Please restructure this sentence.

 

The manuscript needs extensive English editing. I have pointed out a few in the comments below.

Ln 83: jointly – “joint”

Ln 101 : grinded- “ground”

Ln 123: are explained- “explained”

Author Response

Broad Comments:

1. Introduction requires more deeper review on need for the study and how different is PCA based data reduction methods different from other models.

We have considered and improved introduction and added some part regarding PCA line 85-98

 

1. The authors addressed using the model to predict them in unsampled locations. This was not addressed in the results and not even in the conclusion section. Adding more explanation on how the results from this model could be used for predicting soil quality would be useful.

We have clarified this in section 3.4,

Section 3.4.1 where this section showed which model is fitting to each soil property table 7 and also showed the mapping of all soil properties figure 7 .

Section 3.4.2 . mapping of SQI according the results of cluster analysis , Figure 8

 

1. How do you address within-sample variability? How many soil samples did you take from each location? Are these 36 locations treated as one experiment?

Actually, we have chosen the 36 locations according to the variation of topography and soil types and land use changes.

 

 

1. More details on the experiment design and sampling scheme is required. On what basis these 36 locations were chosen? Any underlying assumptions or randomly chosen?

 

We have clarified this in section 2.3

 

Specific Comments:

Ln 15 : “Precision farming” is more standard usage.

We have changed

Ln 25: 13.89 of what? Variability in data?  

We have clarified in Line 25 as it was a percentage of samples

Ln 43-48: Please restructure this sentence.

We have considered and modified

The manuscript needs extensive English editing. I have pointed out a few in the comments below.

Ln 83: jointly – “joint”

we have checked

Ln 101 : grinded- “ground”

Grinded means breaking up soil samples into a smaller size to suitable to chemical analyses

Ln 123: are explained- “explained”

we have checked

 

Finally, we would like to thank you so much for your comments that helped us to improve our manuscript

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Authors have made significant revision to the manuscript based on reviewer comments. Still have some minor concerns that the authors can address to improve readability.

 Again, how many sub-samples (replications) were taken from each location to address within-sample variability?

Manuscript still needs to address “experimental design” properly. Authors pointed me to section 2.3. This is statistical analysis and not experimental design

 

English:

Manuscript still needs English edits. For example, as I previously pointed out “Ground” is the standard conjugation of the verb “grind”. Avoid using “grinded” Ln 121.

Author Response

RESPONSE TO REVIEWERS

MANUSCRIPT     sustainability-1053306

 

Dear associate editor

We have changed the author order

 

POINT BY POINT RESPONSE TO EDITOR/ REVIEWERS

 

 

Reviewer   

Again, how many sub-samples (replications) were taken from each location to address within-sample variability?

We have chosen 36 location and we collected one mixed sample from 0-60 cm in each location  

Section 2.2

 

English:

We have revised the language using English language editing by MDPI

 

Finally, we would like to thank you so much for your comments that helped us to improve our manuscript

Author Response File: Author Response.doc