Medium/Long-Term Efficiency of Struvite for Lettuce (Lactuca sativa L.) Production: Effect on Soil Quality

Round 1

Reviewer 1 Report

Well done. Clarify things given in comments

Comments for author File: Comments.pdf

English very good.

Author Response

Thanks for your comments.

Lettuce crop has been included in abstract in order to clarify as your comment.

A brief explanation of the Spanish methodology  and the biological parameters have been included in materials and methods.

We have check and modified 3.2 paragraph.

 

Reviewer 2 Report

The manuscript title “Medium-long term efficiency of struvite for lettuce production: Effect on soil quality” needs significant improvements and especially the figures. I have major comments and suggestions for authors:

1- In material and methods section the “Total clhorophyll” spelling is wrong, correct this “total chlorophyll”.

 

2- In methods section the authors mentioned that they performed ANOVA! Where is ANOVA table??

 

3- Figure 1: please give a common title to the figures and than explain the sub-sections of the figures such as (a)…, (b)….

 

4- In several figures such as figure 1, 4: what does the capital (A) and small letters (a) means???

 

5- In figure 1: what does the bars indicates??? standard deviation or standard error?? this information is missing in several figures, please add this in all figures.

 

6- In table 3: the calcium values are very high! Why?? twelve thousand - 12,084mg 2,546??? Is it? And K results showed 114,122 mg/kg….. how is it possible???? Please check the literature and verify your results. Also mention in the table legends about the meaning of mg/kg of dry plant weight or fresh and from which plant organ (leaves, stem etc….)??? I think the K values are 114.122 not the 114,122……? Is it?

 

7- In figure 2: “Clorophyll” spelling again wrong! Thoroughly revise the manuscript and correct all the spelling mistakes.

 

8- In figure 2 same issues such as mention in comment 5 [what does the bars indicates??? standard deviation or standard error?? this information is missing in several figures, please add this in all figures].

 

9- Why there is no level of significance in figures 2, 3, 6, and 7.

 

10- Figure 7 and 6: where is standard deviation or standard error??

 

11- Why so many references delete the inappropriate references from the manuscript, keep only relevant references…. It is a research article not a review paper.

1- Thoroughly revise the manuscript and correct all the spelling mistakes.

Author Response

1- In material and methods section the “Total clhorophyll” spelling is wrong, correct this “total chlorophyll”.

Thanks. Revised.

 2- In methods section the authors mentioned that they performed ANOVA! Where is ANOVA table??

According to guide for authors the number of tables is limited, so they have not been included in the manuscript.

 3- Figure 1: please give a common title to the figures and than explain the sub-sections of the figures such as (a)…, (b)….

The title in Figure 1 has been modified according to your suggestion.

 4- In several figures such as figure 1, 4: what does the capital (A) and small letters (a) means???

In the figure legend is included the meaning for capital (A), small (a) and italic letters.

 5- In figure 1: what does the bars indicates??? standard deviation or standard error?? this information is missing in several figures, please add this in all figures.

Thanks. Bars indicates standar deviation. It has been added in all the figures.

 6- In table 3: the calcium values are very high! Why?? twelve thousand - 12,084mg 2,546??? Is it? And K results showed 114,122 mg/kg….. how is it possible???? Please check the literature and verify your results. Also mention in the table legends about the meaning of mg/kg of dry plant weight or fresh and from which plant organ (leaves, stem etc….)??? I think the K values are 114.122 not the 114,122……? Is it?

The values are expressed in dry weight. Considering the soil characteristics (Table 1) the content in plant are in the normal range for this type of plant as you can see, for example, in articles:

“Koudela M, Petříková K. Nutrients content and yield in selected cultivars of leaf lettuce (Lactuca sativa L. var. crispa). Hort. Sci. (Prague). 2008;35(3):99-106. doi: 10.17221/3/2008-HORTSCI”

“Kim, Moo Jung et al. “Nutritional Value of Crisphead ‘Iceberg’ and Romaine Lettuces (Lactuca sativa L.).” The Journal of Agricultural Science 8 (2016): 1”.

 7- In figure 2: “Clorophyll” spelling again wrong! Thoroughly revise the manuscript and correct all the spelling mistakes.

Thanks. Revised.

 8- In figure 2 same issues such as mention in comment 5 [what does the bars indicates??? standard deviation or standard error?? this information is missing in several figures, please add this in all figures].

Thanks. Revised.

 9- Why there is no level of significance in figures 2, 3, 6, and 7.

No significant differences were observed in the values included in figures 2, 3, 6 and 7 according to the statistical analyses as it is included in material and method section.

 10- Figure 7 and 6: where is standard deviation or standard error??

Figure 7 has been included in table 4.

 11- Why so many references delete the inappropriate references from the manuscript, keep only relevant references…. It is a research article not a review paper.

We would prefer the references since they can help the readers.

 

Comments on the Quality of English Language

• Thoroughly revise the manuscript and correct all the spelling mistakes.

 

The manuscript has been thoroughly revised.

Reviewer 3 Report

In this manuscript (horticulturae-2373294) entitled "Medium-long term efficiency of struvite for lettuce production: Effect on soil quality." submitted to Horticulturae, Carolina Mancho and colleagues have evaluated the medium-long term efficiency of struvite (MgNH₄PO₄·6H₂O) (STR) from urban wastewater as a fertilizer in three successive lettuce crops. Through analyzing Crop biomass yield, P uptake, nutritional quality, as well as soil quality, authors concluded that STR treatment yielded similar biomass results to those obtained with conventional P fertilizers in the three successive crops. This study supported STR as a sustainable P-fertilization strategy for lettuce production. This study is an interesting work, I have however several concerns that may be addressed to improve the quality of the work.

1, STR contained P, N and Mg, and authors focused on P-fertilization in this study. However, the effect of STR application on the fertilization of N and Mg, as well as their influences on lettuce crop should be carefully discussed in the revision.  

2, For Figure 1, difference in the cumulative DMY among first, second and third crops should be analyzed and discussed in the revision.  

3, For Figures 2, 3, 6 and 7, significant differences should be analyzed and labelled in the revised figures.

4, The writing issues like spelling, grammar and paragraph division need to be carefully checked and corrected in the revision. For instance, ‘comventional’ in the abstract (page 1) is incorrect, and the paragraph division in page 11 is confusing.

5. Please double-check the reference list. For instance, some journal abbreviations like ‘Plant, Soil Environ.’ and ‘Sustain.’ are incorrect.

The writing issues like spelling, grammar and paragraph division need to be carefully checked and corrected in the revision. For instance, ‘comventional’ in the abstract (page 1) is incorrect, and the paragraph division in page 11 is confusing.

Author Response

 

Comments and Suggestions for Authors

In this manuscript (horticulturae-2373294) entitled "Medium-long term efficiency of struvite for lettuce production: Effect on soil quality." submitted to Horticulturae, Carolina Mancho and colleagues have evaluated the medium-long term efficiency of struvite (MgNH₄PO₄·6H₂O) (STR) from urban wastewater as a fertilizer in three successive lettuce crops. Through analyzing Crop biomass yield, P uptake, nutritional quality, as well as soil quality, authors concluded that STR treatment yielded similar biomass results to those obtained with conventional P fertilizers in the three successive crops. This study supported STR as a sustainable P-fertilization strategy for lettuce production. This study is an interesting work, I have however several concerns that may be addressed to improve the quality of the work.

Thank you for your comments.

 

1, STR contained P, N and Mg, and authors focused on P-fertilization in this study. However, the effect of STR application on the fertilization of N and Mg, as well as their influences on lettuce crop should be carefully discussed in the revision.  

The objective of the study is to evaluate the phosphorus release from estruvite in comparison to other P-contain fertilizers.

Obviously struvite also provides N and Mg to the crop. Anyway, NPK also provides N and K and MAP also provides N. In this study we focus on phosphorus behavior.

The influences on lettuce crop due to the N and Mg presence in struvite has been included in discussion.

 

2, For Figure 1, difference in the cumulative DMY among first, second and third crops should be analyzed and discussed in the revision. 

The  cumulative DMY in figure 1b represent the sum of the yield for the three crop for each fertilizer as it is commented in the discussion.

 

3, For Figures 2, 3, 6 and 7, significant differences should be analyzed and labelled in the revised figures.

No significant differences were found in the data included in these figures.

 

4, The writing issues like spelling, grammar and paragraph division need to be carefully checked and corrected in the revision. For instance, ‘comventional’ in the abstract (page 1) is incorrect, and the paragraph division in page 11 is confusing.

Thanks, the text has been revised.

5. Please double-check the reference list. For instance, some journal abbreviations like ‘Plant, Soil Environ.’ and ‘Sustain.’ are incorrect.

Thanks, the reference list has been revised.

 

Comments on the Quality of English Language

The writing issues like spelling, grammar and paragraph division need to be carefully checked and corrected in the revision. For instance, ‘comventional’ in the abstract (page 1) is incorrect, and the paragraph division in page 11 is confusing.

Thanks, the text has been revised.

Reviewer 4 Report

The current manuscript entitled “Medium-long term efficiency of struvite for lettuce production: Effect on soil quality” by Macho et al. deals with the medium-long-term efficiency of STR from urban wastewater as a fertilizer in three successive lettuce crops. After a careful reading, I found this work appropriate for publication in the Horticulturae journal after major revision. My specific comments are:

1.      Add the scientific name and botanical authority of lettuce in the title.

2.      It is better to rewrite the title of the manuscript as the authors used medium to long-term effects. The current title indicates no such clear information.

3.      The abstract weakly focused on the problem in the first half. It should be rewritten with more focus on structured and scientific writing in the following order: research problem, the aim of this work, study design, major numerical findings, overall outcome, and usefulness of this work.

4.      While writing the abbreviation of phosphorus in abstract line 3, why authors did not add the same for nitrogen and potassium?

5.      Abstract line 8, add a comma after “Here”.

6.      If possible, please avoid using personal terms such as we, us, ours, etc.

7.      The abbreviation for United Nations is missing in introduction line 2.

8.       Please add the sources of lettuce seed and fertilizers procurement.

9.      Tables: Please use a three-line format.

10.   Table 1: it is better to indicate values as mean and SD of at least three analyses. Alter the tile as you can analyze, physiochemical, nutrient, and metal parameters also.

11.   Table 2, is a must to conduct a test of significance to compare different properties of fertilizers.

12.   Please check the abbreviation: agronomic efficiency (RAE)?

13.   I suggest authors improve the histogram of bar charts.

14.   Figure 10: please check values and titles, they are not complete.

15.   The manuscript should be carefully checked for syntax and typo errors.

The manuscript should be carefully checked for syntax and typo errors.

Author Response

Comments and Suggestions for Authors

The current manuscript entitled “Medium-long term efficiency of struvite for lettuce production: Effect on soil quality” by Macho et al. deals with the medium-long-term efficiency of STR from urban wastewater as a fertilizer in three successive lettuce crops. After a careful reading, I found this work appropriate for publication in the Horticulturae journal after major revision. My specific comments are:

Thanks for your coments.

1. Add the scientific name and botanical authority of lettuce in the title.

The scientific name has been include in the title.

2. It is better to rewrite the title of the manuscript as the authors used medium to long-term effects. The current title indicates no such clear information.

The title has been modified according to your suggestion.

3. The abstract weakly focused on the problem in the first half. It should be rewritten with more focus on structured and scientific writing in the following order: research problem, the aim of this work, study design, major numerical findings, overall outcome, and usefulness of this work.

Thanks, the abstract has been modified according your suggestion.

4. While writing the abbreviation of phosphorus in abstract line 3, why authors did not add the same for nitrogen and potassium?

Thanks, the abbreviations has been included.

5. Abstract line 8, add a comma after “Here”.

Added.

6. If possible, please avoid using personal terms such as we, us, ours, etc.

Some sentences has been modified in the text avoiding use personal terms.

7. The abbreviation for United Nations is missing in introduction line 2.

The abbreviation has been included.

8. Please add the sources of lettuce seed and fertilizers procurement.

The sources of lettuce seed and fertilizers procurement has been included.

9. Tables: Please use a three-line format.

I don't know what you mean

10. Table 1: it is better to indicate values as mean and SD of at least three analyses. Alter the tile as you can analyze, physiochemical, nutrient, and metal parameters also.

SD has been included in Table 1 and the title has been modified.

11. Table 2, is a must to conduct a test of significance to compare different properties of fertilizers.

Thanks, but the fertilizers are different and the table is only descriptive.

12. Please check the abbreviation: agronomic efficiency (RAE)?

Thanks.

13. I suggest authors improve the histogram of bar charts.

Thanks.

14. Figure 10: please check values and titles, they are not complete.

Thanks. The original figure is complete. There must have been a problem with the publisher converting it.

15. The manuscript should be carefully checked for syntax and typo errors.

Thanks.

Comments on the Quality of English Language

The manuscript should be carefully checked for syntax and typo errors.

The manuscript has been thoroughly revised.

Reviewer 5 Report

The authors' studies presented in the manuscript are quite promising as they relate to the use of a valuable resource (P) in wastewater treatment. Despite a well-designed laboratory experiment, a number of questions arise:

1. Table 1 contains the data of heavy metals (lead, nickel, cadmium, chromium, zinc) in the soil wich was used for the experiment, but the next part of the manuscript does not have data on the content of these elements after the application of fertilizers.

2. If wastewater was used to obtain STR, then where is the analysis of the content or absence of pollutants (for example, heavy metals) in the resulting fertilizer, which indicates its environmental safety?

3. The availability of phosphorus in the soil, in addition to pH, can be affected by the content of iron and it would be nice to determine its content in the soil, but this can be done in subsequent experiments.

In general, if answers to questions are added to the manuscript, hopefully your work will be improved.

Author Response

Comments and Suggestions for Authors

The authors' studies presented in the manuscript are quite promising as they relate to the use of a valuable resource (P) in wastewater treatment. Despite a well-designed laboratory experiment, a number of questions arise:

Thanks for your comments.

1. Table 1 contains the data of heavy metals (lead, nickel, cadmium, chromium, zinc) in the soil wich was used for the experiment, but the next part of the manuscript does not have data on the content of these elements after the application of fertilizers.

Data of heavy metals in soils after harvest have been included and they have been discussed.

 

2. If wastewater was used to obtain STR, then where is the analysis of the content or absence of pollutants (for example, heavy metals) in the resulting fertilizer, which indicates its environmental safety?

Metals content of fertilizer has been included.

 

3. The availability of phosphorus in the soil, in addition to pH, can be affected by the content of iron and it would be nice to determine its content in the soil, but this can be done in subsequent experiments.

Thanks for your useful suggestion

In general, if answers to questions are added to the manuscript, hopefully your work will be improved.

Thanks.

 

Round 2

Reviewer 2 Report

the authors did sufficient revisions. 

English seems to be fine.

Author Response

Thanks for your comments which have improved the manuscript.

Reviewer 4 Report

It can be published in present form. 

Author Response

Thanks for your comments which have improved the manuscript.

Author Response File: Author Response.docx