The Effect of Grazing Intensity on Vegetation Coverage and Nitrogen Mineralization Kinetics of Steppe Rangelands of Iran (Case Study: Nodoushan Rangelands, Yazd, Iran)

Round 1

Reviewer 1 Report

General comments:

This study tried to assess the effect of grazing intensity on nitrogen mineralization kinetics by changing vegetational cover and composition. The manuscript might contain useful information of nitrogen mineralization kinetics in steppe rangelands; however, I believe that the manuscript has not prepared for submission yet. The main weakness of this study are as follows:

• The introduction section lacks appropriate hypothesis. The authors did not describe a possible mechanism: how grazing intensity affect pasture composition and then nitrogen mineralization kinetics. Due to this problem, an appropriateness and objective of this study are unclear.
• Regarding with the first problem, I do not understand link between the study of grazing intensity and nitrogen mineralization kinetics;
• Statistical analysis should be reconsidered: statistical units and replicates are unclear and multiple comparison is not appropriate for you study design. I strongly recommend that the authors should consult with a statistician about your whole experiment.
• Due to these methodological problems, I cannot evaluate whether the result and discussion of this study is valid or not.

Details:

Lines 42-43: I do not understand exact meaning of these sentences. In line 42, you said grazing increases soil carbon, but you said to the contrary in the next sentence. So. What is your actual intention? In addition, “greenhouse phenomenon intensification” is not so common expression. You have to explain what you mean more clearly and precisely, here.

Lines 44-48: In the previous sentences, you only suggest the contradiction in soli carbon content. Again, you should describe the previous sentences more precisely.

Lines 49- 59: I believe that the present introduction lacks appropriate hypothesis; that is, how grazing intensity affect vegetational composition and then soil nitrogen kinetics. Due to this problem, the objective and validity of study design is unclear.

Lines 63: The following details are needed to ensure the environmental condition in that area: annual mean temperature, rainfall and humidity, seasons (spring to winter or dry and rainy seasons), soil type and type of grazing animals.

Line 66: How did you define the grazing intensity? This is quite important when you compare your results with other studies, because “heavy”, “moderate” and “light” are not the same among the studies.

Lines 68-69: You must define the statistical replicates in this study and the number of samples in each replicate.

Line 75: Describe how to measure the production of each genus.

Lines 94-106: I am confused that this section includes some of results in the first experiment, i.e., the effect of grazing intensity on vegetation and soil properties. I recommend that you should clearly separate or headline the first study and the second study (nitrogen mineralization study).

 Moreover, the authors should explain the link between the first study and second study and an intention of the second study. Actually, I do not understand why the authors choose this study design to test nitrogen mineralization, because in both grazing intensity, Artemisia sieberi is the dominant species, so you do not need 25% of Artemisia sieberi and 75% of Peganum harmala, and 100% of Peganum harmala for your study, and also why you add “1%” organic carbon.

Lines 108-122: You mean that you conducted pot study? And what does actually mean “plant residues”, fresh leaves, stems or whole plant, or litters?

Lines 124-126: It is quite unclear what is the statistical units and replicates? According to the text, you assessed effect of grazing intensity on vegetation coverage and soil properties, and also conducted nitrogen mineralization test; however, it seems that you apply this statistical model for both tests. In the case of “grazing intensity”, it seems you have one pasture in each intensity. So, in this case, how did you randomize the study plots? You must show your statistical design more precisely and thoroughly. In addition, you should not use multiple comparison for analyzing the interaction of time and treatment in nitrogen mineralization test. Anyone cannot understand such complex results in Table 5 and 7.

 I strongly recommend that the authors should consult with a statistician about their entire analysis of this study.

Lines 129-130: You should show the meteorological data to ensure this statement and this sentence should be move to the discussion section.

Line 135: “water through”? You did not show position of sampling plots and water through in the manuscript, so readers cannot confirm this statement. Again, this is also discussion and should not be included in the result section.

Line 135: …has the…

Lines 137-141: These are not your results, so you do not include them here. If you define animals prefer a certain plant to other plants, you should conduct a preference test or, otherwise, you should refer to other studies that compare their palatability.

Line 161: Soil texture should be described in the materials and method section.

Lines 166-168: Remove the sentences. This should be mentioned in the materials and methods section.

Lines 179-182: These sentences should move to the discussion section.

Lines 220-223: These are not result of this study and move to the discussion section.

Table 1: Production should be expressed as dry weight.

Table 3: Soil texture should be described in the materials and method section.

Table 5 and 7: As I suggested above, you should reconsider the analysis. The result of these tables is too complex to understand.

Figure 4: You should not use multiple comparison to assess the time effect.

Author Response

Response 1: Authors of this manuscript would like to thank Reviewer #1 for the careful and detailed reading of our manuscript and for the thoughtful comments and constructive suggestions, which help to improve the quality of our manuscript. Our response (in red) to the general and specific comments follows:

Reviewer 1
This study tried to assess the effect of grazing intensity on nitrogen mineralization kinetics by changing vegetational cover and composition. The manuscript might contain useful information of nitrogen mineralization kinetics in steppe rangelands; however, I believe that the manuscript has not prepared for submission yet. The main weakness of this study are as follows:
•    The introduction section lacks appropriate hypothesis. The authors did not describe a possible mechanism: how grazing intensity affect pasture composition and then nitrogen mineralization kinetics. Due to this problem, an appropriateness and objective of this study are unclear.
•    Regarding with the first problem, I do not understand link between the study of grazing intensity and nitrogen mineralization kinetics;
•    Statistical analysis should be reconsidered: statistical units and replicates are unclear and multiple comparison is not appropriate for you study design. I strongly recommend that the authors should consult with a statistician about your whole experiment.
•    Due to these methodological problems, I cannot evaluate whether the result and discussion of this study is valid or not.
 
Details:
Lines 42-43: I do not understand exact meaning of these sentences. In line 42, you said grazing increases soil carbon, but you said to the contrary in the next sentence. So. What is your actual intention? In addition, “greenhouse phenomenon intensification” is not so common expression. You have to explain what you mean more clearly and precisely, here. This has been edited for more clarification [Lines 49-51].
 
Lines 44-48: In the previous sentences, you only suggest the contradiction in soli carbon content. Again, you should describe the previous sentences more precisely. This has been edited [Lines 49-51].
 
Lines 49- 59: I believe that the present introduction lacks appropriate hypothesis; that is, how grazing intensity affect vegetational composition and then soil nitrogen kinetics. Due to this problem, the objective and validity of study design is unclear. This has been corrected please see [Lines 55-60 and 68-74].
 
Lines 63: The following details are needed to ensure the environmental condition in that area: annual mean temperature, rainfall and humidity, seasons (spring to winter or dry and rainy seasons), soil type and type of grazing animals. Additional information of environmental condition provided, please see [Lines 79-87 and Figure 1].

 
Line 66: How did you define the grazing intensity? This is quite important when you compare your results with other studies, because “heavy”, “moderate” and “light” are not the same among the studies.
For the method described please see [Lines 213-216].
 
Lines 68-69: You must define the statistical replicates in this study and the number of samples in each replicate.
This has been edited for more clarification please see [Lines 223-224].
 
Line 75: Describe how to measure the production of each genus.
This has been added for more clarification please see [Lines 224-225].

 
Lines 94-106: I am confused that this section includes some of results in the first experiment, i.e., the effect of grazing intensity on vegetation and soil properties. I recommend that you should clearly separate or headline the first study and the second study (nitrogen mineralization study).
 Moreover, the authors should explain the link between the first study and second study and an intention of the second study. Actually, I do not understand why the authors choose this study design to test nitrogen mineralization, because in both grazing intensity, Artemisia sieberi is the dominant species, so you do not need 25% of Artemisia sieberi and 75% of Peganum harmala, and 100% of Peganum harmala for your study, and also why you add “1%” organic carbon.
Sentences were added to relate the sections. please see [Lines 250-266]. A reference was provided for adding 1% organic carbon.
 
Lines 108-122: You mean that you conducted pot study? And what does actually mean “plant residues”, fresh leaves, stems or whole plant, or litters? Yes, a pot study conducted and the whole above-ground part of the plants were used for the experiment. Line 263 edited for clarification.
 Lines 124-126: It is quite unclear what is the statistical units and replicates? According to the text, you assessed effect of grazing intensity on vegetation coverage and soil properties, and also conducted nitrogen mineralization test; however, it seems that you apply this statistical model for both tests. In the case of “grazing intensity”, it seems you have one pasture in each intensity. So, in this case, how did you randomize the study plots? You must show your statistical design more precisely and thoroughly. In addition, you should not use multiple comparison for analyzing the interaction of time and treatment in nitrogen mineralization test. Anyone cannot understand such complex results in Table 5 and 7.
 I strongly recommend that the authors should consult with a statistician about their entire analysis of this study.
Statistical plans were presented separately for different studies. The whole study area is single rangeland that has the same plant type but has been under different management. And the pastures with heavy grazing are the pastures around the water source that the livestock passes through every day. First, the key area was identified in each study site and then random points were selected by moving in that area and throwing stones. In order to better understand Tables 5 and 7 (of the original submitted manuscript), they were converted into graphs (now in Figures 7 and 10 of the revised/resubmitted manuscript).
 
Lines 129-130: You should show the meteorological data to ensure this statement and this sentence should be move to the discussion section.
 The source is cited [21] for drought in the area.
Line 135: “water through”? You did not show position of sampling plots and water through in the manuscript, so readers cannot confirm this statement. Again, this is also discussion and should not be included in the result section.
 
Line 135: …has the… Line 300 edited as “has the”
 
Lines 137-141: These are not your results, so you do not include them here. If you define animals prefer a certain plant to other plants, you should conduct a preference test or, otherwise, you should refer to other studies that compare their palatability.
 Reference [11] provided for palatability 
Line 161: Soil texture should be described in the materials and method section.
Reference [18] provided to refer to soil texture determination method. 

Lines 166-168: Remove the sentences. This should be mentioned in the materials and methods section.
The authors deleted the sentences. Please see the edited section from line 334 to 339
 
Lines 179-182: These sentences should move to the discussion section.
This has been edited and moved to the discussion section.

Lines 220-223: These are not result of this study and move to the discussion section.
 This has been edited and moved to the discussion section.

Table 1: Production should be expressed as dry weight.
 The footnote of Table 1 edited * dry weight 
Table 3: Soil texture should be described in the materials and method section.
The authors provided reference [18] to refer to the soil texture determination method. 
 Table 5 and 7: As I suggested above, you should reconsider the analysis. The result of these tables is too complex to understand.
 In order to better understand Tables 5 and 7 (of the original submitted manuscript), they were converted into graphs (now in Figures 7 and 10 of the revised/resubmitted manuscript).
Figure 4: You should not use multiple comparison to assess the time effect.
Please see lines 297-298 for additional information on data analysis, with respect to reviewer #1 opinion, the authors of this manuscript after consulting with the statisticians believe that the proper and accurate data analysis was done to synthesis the results of this study.   

Author Response File: Author Response.pdf

Reviewer 2 Report

Disparity between the methodological and the results part of the Abstract - short results part.

Author Response

Response to reviewer #2: The authors thank Reviewer #2 for thoughtful comments and constructive suggestions on this manuscript. 

Reviewer 2

Point 1: Extensive editing of English language and style required
Point 2: Disparity between the methodological and the results part of the Abstract - short results part.
Response 1 and 2: According to point 1 of reviewer #2, authors rewrote and revised the Abstract from lines 22 to 25 and line 34, introduction from lines 46-48, 51-57, and 65-71, Methods and Materials from line 77-85 and 154-157 and Figure 1 added. Sentences were added to the abstract and discussion to relate the sections. Grammatical errors were edited throughout the manuscript.

Reviewer 3 Report

The authors propose a manuscript titled “The Effect of Grazing Intensity on Vegetation Coverage and Nitrogen Mineralization Kinetics of Steppe Rangelands of Iran (Case Study: Nodoushan Rangelands, Yazd, Iran)”. The authors discuss on grazing can affect the cycling of nutritional elements in soil by making changes to the vegetation coverage throught a study aims to investigate the effect of rangeland exploitation on vegetation coverage and nitrogen kinetics. To support their study three experimental sites of light, moderate, and heavy grazing in Nodoushan rangelands of Yazd province were selected. Very interesting the data about the treatments control with Artemisia sieberi and Peganum harmala. The manuscript is original in the data compared to other similar articles. However I believe it is necessary to implement the maniscript with some crucial concepts that the authors will have no problem to accepting as they are designed to improve the work.

Introduction

• Lines 36-37. Please complete the concept in this way: “…grazing is a major determinant of soil and vegetation that can affect the structure and function of vegetation coverage in many ways [1,2], for which it is necessary to establish a grazing plan for the conservation of these ecosystems and their plant species useful for livestock (Perrino et al. 2021, Bell et al. 2013).
• Lines 37-38. It can also influence the nutrient flows and the performance of rangeland ecosystems (CHOOSE A REFERENCE).

References to be added:

• Perrino, E.V., Magazzini, P., Musarella, C.M., Management of grazing “buffalo” to preserve habitats by Directive 92/43 EEC in a wetland protected area of the Mediterranean coast: Palude Frattarolo, Apulia, Italy. Euro-Mediterranean Journal for Environmental Integration2021, 6, 32. doi: 10.1007/s41207-020-00235-2
• Bell, L.W.; Moore, A.D.; Kirkegaard, J.A. Evolution of crop–livestockintegration systems that improve farm productivity and environmental per-formance in Australia. European Journal of Agronomy 2013. doi: 10.1016/j.eja.2013.04.007

2. Materials and Methods

• Please a georefrenced map of studied area. Where is the steppe grasslands of the Nodoushan area in Yazd province?
• Line 63. Specify the geographic system used (WGS84?)
• Lines 86-87. The authors have adopted a physiognomic sampling system “Plant sampling was performed on the predominant species in terms of general physiognomy”. For my point of view it would have been better and appropriate to use the phytosociological method (Braun-Blanquet 1932), more precise. However this is a choice of the authors and cannot be a reason for acceptance of the work.
• Line 95. Please report the scientific name in the complete way when the species is reported for the firsttime in the manuscript , e.g.:
• Artemisia sieberi Besser
• Stipa barbata
• Peganum harmala

3. Results

• Line 132. Following my previous comment complete in the correct way and please check whole document
• Lactuca orientalis
• Astragalus bisulcatus (Hook.) A.Gray
• Hertia angustifolia (DC.) Kuntze

• Line 137.
• Poa annua

4. Discussion

Well done. I would spend a few more words for Peganum harmala, a very interesting species not edible by grazing but used by man. See and read the following works ior others in this topic

• Abbott, L.B., Bettmann G.T., Sterling. T.M., 2008. Physiology and recovery of African rue (Peganum harmala) seedlings under water-deficit stress. Weed Science, 56: 52-57.
• Aslam N., Wani A.A., Nawchoo I.A., Bhat M.A., 2014. Distribution and medicinal importance of Peganum harmala - a review. Int. J. Adv. Res., (2)2: 751-755.

5. Conclusion

Lines 336-337. Please if possible complete the conclusion of this crucial concept: “…Hence, more attention should be paid to implement effective strategies for  proper management and renewal of vegetation coverage, enhancing the species useful for grazing (choose a reference), those useful for humans and in particular the Crop Wild Relatives (Perrino and Perrino 2020, Maxted et al. 2006, 2016), on the key of environmental sustainability”.

References to be added

• Perrino, E.V.; Perrino P. Crop wild relatives: know how past and present to improve future research, conservation and utilization strategies, especially in Italy: a review. Genetic Resource and Crop Evolution 2020, 67, 1067–1105. Doi: 10.1007/s10722-020-00930-7
• Maxted, N.; Ford-Lloyd, B.V.; Jury, S.L.; Kell, S.P.; Scholten, M.A. Towards a definition of a crop wild relative. Biodiversity Conservation 2006, 15, 2673–2685. https://doi.org/10.1007/ s10531-005-5409-6
• Maxted, N.; Ehsan Dulloo, M.; Ford-Lloyd, B.V. (eds) Enhancing crop genepool use: capturing wild relative and landrace diversity for crop improvement. CAB International, Wallingford, 2016.

References

Please check whole document and follows the guidelines of the journal

Author Response

Response to reviewer #3: Authors of this manuscript appreciate the positive feedback from Reviewer #3 for the detailed reading of our manuscript and for the valuable comments. Our response (in red) follows:
Reviewer 3
The authors propose a manuscript titled “The Effect of Grazing Intensity on Vegetation Coverage and Nitrogen Mineralization Kinetics of Steppe Rangelands of Iran (Case Study: Nodoushan Rangelands, Yazd, Iran)”. The authors discuss on grazing can affect the cycling of nutritional elements in soil by making changes to the vegetation coverage throught a study aims to investigate the effect of rangeland exploitation on vegetation coverage and nitrogen kinetics. To support their study three experimental sites of light, moderate, and heavy grazing in Nodoushan rangelands of Yazd province were selected. Very interesting the data about the treatments control with Artemisia sieberi and Peganum harmala. The manuscript is original in the data compared to other similar articles. However I believe it is necessary to implement the manuscript with some crucial concepts that the authors will have no problem to accepting as they are designed to improve the work.
Point 1: Introduction
•    Lines 36-37. Please complete the concept in this way: “…grazing is a major determinant of soil and vegetation that can affect the structure and function of vegetation coverage in many ways [1,2], for which it is necessary to establish a grazing plan for the conservation of these ecosystems and their plant species useful for livestock (Perrino et al. 2021, Bell et al. 2013).
•    Lines 37-38. It can also influence the nutrient flows and the performance of rangeland ecosystems (CHOOSE A REFERENCE).
 Response 1: Introduction edited please see lines 40-43 and 49-50.
Point 2: References to be added:
•    Perrino, E.V., Magazzini, P., Musarella, C.M., Management of grazing “buffalo” to preserve habitats by Directive 92/43 EEC in a wetland protected area of the Mediterranean coast: Palude Frattarolo, Apulia, Italy. Euro-Mediterranean Journal for Environmental Integration2021, 6, 32. doi: 10.1007/s41207-020-00235-2
•    Bell, L.W.; Moore, A.D.; Kirkegaard, J.A. Evolution of crop–livestockintegration systems that improve farm productivity and environmental per-formance in Australia. European Journal of Agronomy 2013. doi: 10.1016/j.eja.2013.04.007
Response 2: References (Page 14) Line 504-508 added, edited and properly formatted.

Point 3: Materials and Methods
•    Please a georefrenced map of studied area. Where is the steppe grasslands of the Nodoushan area in Yazd province? Figure 1 added for clarification
•    Line 63. Specify the geographic system used (WGS84?) Edited please see lines 76-86 and Figure 1. 
•    Lines 86-87. The authors have adopted a physiognomic sampling system “Plant sampling was performed on the predominant species in terms of general physiognomy”. For my point of view it would have been better and appropriate to use the phytosociological method (Braun-Blanquet 1932), more precise. However this is a choice of the authors and cannot be a reason for acceptance of the work. The referee's description is correct, however, this study was based on the general physiognomy of the studied area.
•    Line 95. Please report the scientific name in the complete way when the species is reported for the first-time in the manuscript , e.g.: Line 193-197: Edited as Artemisia sieberi Besser, Stipa barbata Desf., and Peganum harmala L.
•    Artemisia sieberi Besser
•    Stipa barbata
•    Peganum harmala
Point 4: Results
•    Line 132. Following my previous comment complete in the correct way and please check whole document Line 242-243: Edited as Lactuca orientalis (Boiss.) Boiss, Astragalus bisulcatus (Hook.) A. Gray, and Hertia angustifolia (DC.) Kuntze
Lactuca orientalis
Astragalus bisulcatus (Hook.) A. Gray
Hertia angustifolia (DC.) Kuntze
     Line 137. Line 244: Edited as Poa annua L.
•    Poa annua
Point 5: Discussion
Well done. I would spend a few more words for Peganum harmala, a very interesting species not edible by grazing but used by man. See and read the following works or others in this topic
•    Abbott, L.B., Bettmann G.T., Sterling. T.M., 2008. Physiology and recovery of African rue (Peganum harmala) seedlings under water-deficit stress. Weed Science, 56: 52-57.
•    Aslam N., Wani A.A., Nawchoo I.A., Bhat M.A., 2014. Distribution and medicinal importance of Peganum harmala - a review. Int. J. Adv. Res., (2)2: 751-755.
Point 6. Conclusion
Lines 336-337. Please if possible complete the conclusion of this crucial concept: “…Hence, more attention should be paid to implement effective strategies for proper management and renewal of vegetation coverage, enhancing the species useful for grazing (choose a reference), those useful for humans and in particular the Crop Wild Relatives (Perrino and Perrino 2020, Maxted et al. 2006, 2016), on the key of environmental sustainability”.
References to be added
Perrino, E.V.; Perrino P. Crop wild relatives: know how past and present to improve future research, conservation and utilization strategies, especially in Italy: a review. Genetic Resource and Crop Evolution 2020, 67, 1067–1105. Doi: 10.1007/s10722-020-00930-7
Maxted, N.; Ford-Lloyd, B.V.; Jury, S.L.; Kell, S.P.; Scholten, M.A. Towards a definition of a crop wild relative. Biodiversity Conservation 2006, 15, 2673–2685. https://doi.org/10.1007/ s10531-005-5409-6
Maxted, N.; Ehsan Dulloo, M.; Ford-Lloyd, B.V. (eds) Enhancing crop gene pool use: capturing wild relative and landrace diversity for crop improvement. CAB International, Wallingford, 2016.
Response 6. The conclusion section was revised. Please see lines 480-482.

Point 7. References
Please check the whole document and follows the guidelines of the journal
Response 7. The authors followed the Sustainability journal’s guidelines and properly formatted the references. Please see Page 14 and 15 of the manuscript.

Author Response File: Author Response.docx