Physical, Chemical, and Biological Indicators of Soil Quality in Mediterranean Vineyards under Contrasting Farming Schemes

Round 1

Reviewer 1 Report

The current study entitled “Physical, chemical and biological indicators of soil quality in Mediterranean vineyards under different agricultural intensity” is good. For a better understanding in-depth, it is need for time to work on this topic. Furthermore, achieving potential benefits by using current technology depends on extensive research work for more exploration. Although the experiment is well organized, I suggest a major revision due to the following deficiencies.

Major Concerns

Title

• It is fine.

Abstract

• The systematic abstract is missing. Introduce the need for study in 1-2 lines.
• Please give a clear-cut point problem source as a problem statement that is tackled in the current study.
• Give a logical reason for selecting the current strategy, i.e., Physical, chemical, and biological indicators of soil quality.
• Quantitative data is also essential to support your conclusion. I request that the authors carefully check and rewrite the results part of the abstract. Please provide a percentage increase or decrease in the result part.
• Please provide a definitive conclusion withdrawn through research in a single line.
• Please conclude with a statement that shows a knowledge gap covered, potential beneficiaries, and specific recommendations.
• Give future perspective in a single line. At least declare one best result.
• As per standard suggestions, please avoid using title words as keywords.

Introduction

• Please follow the title in the introduction section, i.e., soil physical, chemical, and biological attributes and their impact on nutrients in the soil, nutrients uptake in vineyards, different agricultural intensity, knowledge gap, hypothesis, and aims.
• Also, provide a novelty statement at the end. What new things have authors done or correlated in this research compared to old ones?
• Would you please give a single line about the knowledge gap your research has covered along with the SMART (specific, measurable, achievable, realistic, and time-specific) hypothesis statement?

Material and methods

• What were the selection criteria for sampling? Give a reference for it.
• Please make subheadings, especially statistical analysis, in the M&M.

Results

• Please provide percentage increases and decreases in the studied attributes.
• I request that the authors they can provide Pearson correlation and parallel plots for a better understanding of the data.
• Chord diagrams can also be made to clear the percentage contribution of each studied attribute.

Discussion

• Please provide a definite mechanism associated with the results. The discussion part is fragile.
• Please incorporate at least 3-4 paragraphs showing the principal mechanism for which authors got such results.

Conclusion

• The conclusion is so much descriptive. Please provide a conclusive conclusion.
• Add the targeted beneficiary audience who will get benefit from this research.
• Also, give clear-cut recommendations
• Give future prospective regarding this research.

Author Response

Major Concerns

Abstract

• The systematic abstract is missing. Introduce the need for study in 1-2 lines.
• Please give a clear-cut point problem source as a problem statement that is tackled in the current study.
• Give a logical reason for selecting the current strategy, i.e., Physical, chemical, and biological indicators of soil quality.
• Quantitative data is also essential to support your conclusion. I request that the authors carefully check and rewrite the results part of the abstract. Please provide a percentage increase or decrease in the result part.
• Please provide a definitive conclusion withdrawn through research in a single line.
• Please conclude with a statement that shows a knowledge gap covered, potential beneficiaries, and specific recommendations.
• Give future perspective in a single line. At least declare one best result.
• As per standard suggestions, please avoid using title words as keywords.

We have reviewed the abstract and the key words following your advice.

Introduction

• Please follow the title in the introduction section, i.e., soil physical, chemical, and biological attributes and their impact on nutrients in the soil, nutrients uptake in vineyards, different agricultural intensity, knowledge gap, hypothesis, and aims.
• Also, provide a novelty statement at the end. What new things have authors done or correlated in this research compared to old ones?
• Would you please give a single line about the knowledge gap your research has covered along with the SMART (specific, measurable, achievable, realistic, and time-specific) hypothesis statement?

Thank you for your helpful scheme. We have reviewed the introduction in this sense

Material and methods

• What were the selection criteria for sampling? Give a reference for it.

I am very sorry, but we don’t understand the question. If you wonder why we chose these vineyards, the reason is that it was the only triad of vineyards we were able to find representing intensive, regenerative and minimum impact viticulture under comparable conditions of soil, climate and land use history. This is better explained now in the description of the study site.

If you refer to the spatial distribution of our sampling points, it responds to the intention to represent the spatial heterogeneity of each field while avoiding possible disturbances caused by the passing of the machinery between trellises. These disturbances are particularly likely in the case of the intensive vineyards in response to diverse eventualities and are seldom reported to the scientists by the intensive farmers, that are far less aware of soil responsiveness to their actions than “sustainable” farmers.  Now we have explained the reasons of this distribution in the “Sampling design” section.

• Please make subheadings, especially statistical analysis, in the M&M
• We have combined several isolated paragraphs into less paragraphs containing, each of them, all information referent to every specific statistical analyses. We hope that this makes reading more friendly.

Results

• Please provide percentage increases and decreases in the studied attributes.

Provided in table 2 for the selected indicators

• I request that the authors they can provide Pearson correlation and parallel plots for a better understanding of the data.

We are very sorry, but we don’t understand your request: Pearson correlations between what and what?

• Chord diagrams can also be made to clear the percentage contribution of each studied attribute.

When reviewing our graphs for the DbLM and dbRDA analyses for the effect of soil physical and chemical properties on the microbial functional profile of the three vineyards, we found that the graphs previously included in the manuscript were mistaken. We have now included the correct graph (and the correspondent explanation) and we hope that everything is clearer now. We honestly think that chord diagrams are not going to be clarifying in our case

Discussion

• Please provide a definite mechanism associated with the results. The discussion part is fragile.
• Please incorporate at least 3-4 paragraphs showing the principal mechanism for which authors got such results.

We have rewritten the discussion  following your suggestions

Conclusion

• The conclusion is so much descriptive. Please provide a conclusive conclusion.
• Add the targeted beneficiary audience who will get benefit from this research.
• Also, give clear-cut recommendations
• Give future prospective regarding this research.

Done, Thank you

Author Response File: Author Response.pdf

Reviewer 2 Report

Physical, chemical and biological indicators of soil quality in Mediterranean vineyards under different agricultural intensity

Studying different indicators of soil quality even in Mediterranean vineyards under different agricultural intensities for sure is very interesting topic! But this MS has several scientific problems starting from the title as follows:

The title “intensity” should be intensities and the biological indicators are dominant not physical or chemicals???

Very general mistake: there is no paragraph consists of one or 2 sentences?? You can find this in entire MS and definitely this is not accepted. Any paragraph should at least 5-7 sentences???

It is not acceptable to include this MS “as an original article more than 150 refs.” what about the review??

Any general study on locations like this MS, it should include a map for these locations?

In table 1, the values of soil pH can not never statistically analyzed because the pH values are not real values but – log????

In Table, the authors should present all details about the selected locations which mainly location, and their other practical management, etc.

In general, the values of max., min., and mean should present in the results???

I did not find the measurement of heavy metals (HMs) like Zn or Cu, etc. especially the authors mentioned that pesticides are commonly used? Are these HMs being in toxic or in normal levels? This is very important parameter for soil quality and important indicator???

The authors mentioned:

“Due to spatial soil variability, and because of the nature of the farming activity, we 161 were not able to replicate our vineyards.”

This is not correct because simply, the samples were collected in May 2019, what about in winter, or in autumn what is the situation for these measurements? Totally will be different so, at least 2-3 times the samples should be repeated?? In general, one time is totally not enough to evaluate these indications?????

Why the authors did not take plant samples?? This is very important??

The authors mentioned:

“In July 2019, we visited the vineyards again for sampling. We took four soil cores (25 181 cm2 section and 15 cm deep) at each of the 16 sampling points of each vineyard (Fig. 2).”

For soil biological parameters, sampling should take from the rhizosphere “very close to plant roots”???

For soil biological indicators, soil enzymes are essential to measure, they are totally absent!!!

I think these results are not reliable and need more work

Author Response

Studying different indicators of soil quality even in Mediterranean vineyards under different agricultural intensities for sure is very interesting topic! But this MS has several scientific problems starting from the title as follows:

The title “intensity” should be intensities and the biological indicators are dominant not physical or chemicals???

Thank you for your remark. We have adapted the title to your comment-

Very general mistake: there is no paragraph consists of one or 2 sentences?? You can find this in entire MS and definitely this is not accepted. Any paragraph should at least 5-7 sentences???

We have compacted the paragraphs as far as possible

It is not acceptable to include this MS “as an original article more than 150 refs.” what about the review??

Sorry… We don’t understand your comment about the review. Do you want us to reduce the number of references?

Any general study on locations like this MS, it should include a map for these locations?

Included now in Fig 1.

In table 1, the values of soil pH cannot never statistically analyzed because the pH values are not real values but – log????

c Biol. 84, 335-339 / Murphy, M. R. (1982) Analyzing and presenting pH data. Journal of Dairy Science, 65(1), 161-163.)

Yes, of course, there are differences between the distribution of the [H+] and the distribution of the pH (log - [H+]), mainly affecting the asymmetry of the standard deviation.

We have performed the ANOVA on the antilogarithm of the pH and, despite this effect, the significance of the differences between treatments are exactly the same than when performing the ANOVA on the pH (please find teh details in the attached PDF)

Therefore, to make the work more comprehensive, we have conserved the ANOVA on the pH values, that is the most used approach in literature, despite its inaccuracy.

In Table, the authors should present all details about the selected locations which mainly location, and their other practical management, etc.

We have tried to put these data in a table but the description of the practices at each site is too long to be inserted in the correspondent column of the table harmoniously.  We think that, since there are only three treatments, these data (location included) are easier to be found in the text

In general, the values of max., min., and mean should present in the results???

In tables included in the main text the most usually form to express the results is Mean ± SdE or Mean ± DesvEst.

If you consider that Max and Min values data are necessary, we can include them in an extended table in Annexes

I did not find the measurement of heavy metals (HMs) like Zn or Cu, etc. especially the authors mentioned that pesticides are commonly used? Are these HMs being in toxic or in normal levels? This is very important parameter for soil quality and important indicator???

It was not our intention to compare the the vineyards for heavy metals, mainly because of copper and sulfur are used to control fungi in vine growing both in intensive and in any other alternative (and more “sustainable”) farming strategy. There is active research about possible alternatives to control fungal attacks but, up to now, all vine growers are using these two metals, to the point that the label “Ecological vine” allows, in the EU, the use of copper and sulfur,

Anyway, the map of heavy metal content in the soils of Catalonia shows that Cu concentrations in soils range from 2,5 to 1155 mg kg^-1 with median = 16,7 mg kg^-1. The highest Cu concentrations are very sporadic and correspond to old industrial areas around Barcelona. To our knowledge and confirmed by our own unpublished results in other Catalan vineyards, the levels of copper in soil are far below the legal limits stablished in most EU countries.

Bech, J., et al. (2008). Pedogeochemical mapping of Cr, Ni, and Cu in soils of the Barcelona Province (Catalonia, Spain): relationships with soil physico-chemical characteristics. Journal of Geochemical Exploration, 96(2-3), 106-116.

The authors mentioned:

“Due to spatial soil variability, and because of the nature of the farming activity, we were not able to replicate our vineyards” This is not correct because simply, the samples were collected in May 2019, what about in winter, or in autumn what is the situation for these measurements? Totally will be different so, at least 2-3 times the samples should be repeated?? In general, one time is totally not enough to evaluate these indications?????

The samples were collected in July 2019.

Our sentence is totally correct in terms of spatial heterogeneity at the regional scale: there is not another replicate of this triad of management types on the same type on soil, under the same climate and using the same varieties of vine trees.

About your demand of time series of samples, it would have been our will, but some months after sampling, one of the vineyards (the intensive one) was rented to new owners who modified the management and joined the regenerative strategy. Therefore, a second sampling campaign has not sense. This is one of the reasons why we mention “because of the nature of the farming activity” as one explanation to our design, that is not an experimental design but follows the real activity of farmers.

However, our sampling strategy is correct in terms of a snapshot comparison between treatments. Our sampling date was chosen as far as possible of the last tilling date in the intensive vineyard, just two days before the next one, to avoid the effect of just temporary disturbances in this field derived of this action that does not occur in the two other fields. 

Why the authors did not take plant samples?? This is very important??

Because our experiment was about effects management type on soil, not on plants. We have data provided by the farmers about the yield of the three vineyards, but we did not consider relevant these data in the context of this manuscript

The authors mentioned:

“In July 2019, we visited the vineyards again for sampling. We took four soil cores (25 cm2 section and 15 cm deep) at each of the 16 sampling points of each vineyard (Fig. 2).” For soil biological parameters, sampling should take from the rhizosphere “very close to plant roots”???

I am sorry but I disagree. The community is totally different in bulk soil and in the rhizosphere. We sample the rhizosphere when we are following the effect of a treatment on plant-soil relationships which was not our question. If this were the case, the sampling design would be forcefully different, so we had to choose where to put your focus.

For soil biological indicators, soil enzymes are essential to measure, they are totally absent!!!

The Microrresp test is a proxy of the microbial catabolic enzymes present in soil. Microbes use specific enzymes to decompose (more or less intensely) the carbon substrates of diverse chemistry we offer to them.

I think these results are not reliable and need more work

Sorry … which ones????

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Dear Authors

I am sorry to say that my point of sampling criteria is not conveyed to you. Your whole study is based on sampling. There are certain sampling designs as per the requirement of experimentation objectives. i.e., random sampling, systematic sampling, etc. In each type, there are further subdivisions. i.e., zig-zag manner, grid manner, zone manner, stratified manner, Rectangular manner, etc. In each division, scientifically sampling unit scales are also defined. All these things are compulsory for the achievement of a representative sample of any site. If some one does not follow these rules then sampling cannot be a true representative of the site. Please explain all these things. Otherwise, I am afraid that your article can not be accepted. Because there is no space for general statements in science. We have to follow scientific methods to deliver justifiable results.

Regards

Author Response

Thank you very much for clarifying the question. We are sorry that we did not understand your demand the first time.

At each field, we did a systematic sampling using a zigzag transect with the origin of the transect randomly selected. We have included this information in the manuscript (Methods).

Sampling agricultural areas, and particularly woody crops, is delicate since there are clear spatial patterns in the fields in addition to those that are not evident.

In the case of vineyards, there are two very different environments, corresponding to the inter-rows and to the rows of trees. Had we wanted to sample the whole field, we should have performed a stratified sampling, separating both environments. Since we did not have enough resources (the work was paid by the farmers as a part of their will to know if they were working in a sustainable way) to duplicate the number of samples, we had to choose one of them.

Our transects had this shape to identify possible invisible soil patterns, that were not detected.

We hope that this is clear now.

We have also reviewed the manuscript in detail for English.

Author Response File: Author Response.docx

Reviewer 2 Report

thank you for your answer to my comments 

Author Response

Thank you very much too for your guidance