Soil Microbial Community Responses to Cyanobacteria versus Traditional Organic Fertilizers

Round 1

Reviewer 1 Report

The manuscript explores the impacts of diverse organic fertilizers on soil microbial communities in varying soil types and depths and elucidate the effects of these fertilizers on soil microorganisms in certified organic cucumber and peach orchard settings. The topic is interesting and the manuscript is well conducted. I suggest that it can be considered for published after the major revision. However, I have some specific comments for this manuscript as following.

1.       I suggest the authors add hypothesis in the final part of the introduction.

2.       The authors focus on the soil layer including 0-2.5 cm and 2.5-7.5 cm, maybe it is the most sensitive layer to fertilizers, but how is the responses of the deeper layer to fertilizers in this research? I suggest the authors should discuss that in the manuscript.

3.       It seem that something missing in the Figure. 1, please check it.

4.       In table 3 and table 4, I wonder how many replicates in your treatments? Please add it below the table.

Minor editing of English language required

Author Response

Thank you for your review. Our responses are written below your suggestions in italics.

1. I suggest the authors add hypothesis in the final part of the introduction.

We have added hypotheses to the text at the end of the introduction. Please see lines 87-89.

2. The authors focus on the soil layer including 0-2.5 cm and 2.5-7.5 cm, maybe it is the most sensitive layer to fertilizers, but how is the responses of the deeper layer to fertilizers in this research? I suggest the authors should discuss that in the manuscript.

While considering the importance of investigating deeper soil layers, our current emphasis is directed toward exploring the impact of organic fertilizer application on microbial communities and biomass composition within the shallower (0-2.5 cm and 2.5-7.5 cm) depths. This focus stems from observations of reduced bacterial abundance as depth increases, as outlined in lines 74-81 of the introduction. In a short-term study such as ours, changes at deeper depths are generally not expected.

3. It seem that something missing in the Figure. 1, please check it.

I appreciate your response. However, could you provide more specific details about any potential elements that might be missing in Figure 1? The PCA figure seems to comprehensively present all the components visually, and the accompanying caption provides a detailed explanation of its contents.

4. In table 3 and table 4, I wonder how many replicates in your treatments? Please add it below the table.

Thank you for your suggestion. We have incorporated it as you recommended. Kindly review lines 293 and 312.

Reviewer 2 Report

The present manuscript describes the effect of different organic sources on the microbial community in the soil. Paper is written and presented in a nice way. The results are a nice approval of previously reported investigations. There are number of such articles previously published reporting on the effects of different fertilizer sources on soil fertility and biology. 

-Abstract described a summary of results and concluded that cyanobacteria-based fertilizers have significant scope in sustainable agricultural practices.

-Organic fertilizer are important to maintain soil health and sustainable soil fertility. There are number of such articles previously published reporting on the effects of different fertilizer sources on soil fertility and biology. However, present article describes the effect of cyanobacteria based sources on microbial community.

-Materials and methods are clearly described.

-Results and discussion are written well.

-Results are concluded in a nice way.

Author Response

We greatly appreciate your review and feedback. Thank you very much.

Reviewer 3 Report

The research presented in the manuscript is of high impact and importance since it uses non-conventional sources to improve the soil quality and ecosystem health. Moreover, this technique can be a good sustainable approach to improve crop productivity.

Abstract is complete from all aspects.

Introduction is good and provides enough background research on the subject matter. Moreover, the objectives formulated are in accordance to the research presented in the manuscript.

Materials and methods should be elaborated more in following terms

1.       The primary analysis of organic fertilizers particularly the cyanobacterial analysis for pH and nutrients.

2.       Because the cyanobacterial fertilizers have been used as liquid, it has not been mentioned that how, in what solvent this has been prepared and in what ratio it has been used in the soil.

3.       The identification of microbial communities has not been described because fatty acid analysis produces results for biomass not for the identification of microbial groups.

Author Response

Thank you for your review. We respond to each of your comments below in italics.

Materials and methods should be elaborated more in following terms

1. The primary analysis of organic fertilizers particularly the cyanobacterial analysis for pH and nutrients.

Thank you for your valuable suggestion. We added the pH to line 110, along with the N concentration. The nutrient concentrations of the other fertilizers used are shown in lines 103-110 and 118-121.

2. Because the cyanobacterial fertilizers have been used as liquid, it has not been mentioned that how, in what solvent this has been prepared and in what ratio it has been used in the soil.

The cyanobacteria were cultivated in a modified Allen and Arnon media and applied directly with no processing of any kind. We have added the media information in lines 108-109. Details are described in citation #10: Barminski et al., 2016.

3. The identification of microbial communities has not been described because fatty acid analysis produces results for biomass not for the identification of microbial groups.I appreciate your review and feedback. Thank you very much. While it is true that fatty acid analysis does not directly identify specific microbial groups at the species or genus level, it can still provide valuable insights into the composition of microbial communities. The phospholipid fatty acid (PLFA) analysis we conducted allows us to identify the types of lipids present in the sample. These lipids are essential components of microbial cell membranes and vary between different microbial groups.

Reviewer 4 Report

This research examined the “Soil Microbial Community Responses to Cyanobacteria Versus Traditional Organic Fertilizers”. This current study is interesting. The manuscript has shown progress to the current scientific research and qualified enough for publishing in “Agriculture”. However, some comments need to be addressed with minor revisions before being considered for publication.

 

1.       Authors should incorporate soil depth and soil type in the abstract section.

2.       The authors only mentioned that the experiment was conducted during the growing season (2014 and 2015); however, the authors should briefly describe the season, environmental conditions, soil texture, and water-holding capacity for the two trials.

3.       Authors should mention the initial physicochemical properties of each manure.

4.       Why did the authors only test cucumbers in August 2014 and peaches in August 2014 and 2015?

5.       Why did the authors pick cucumber and peaches as their test crops? One is an annual plant, whereas the other is a perennial plant.

6.       Authors should mention the changes in soil physicochemical properties after the addition of the manures in both experiments.

may be improved

Author Response

Thank you for your review. We respond to your comments in italics below.

1. Authors should incorporate soil depth and soil type in the abstract section.

In the abstract, we referred to "varying soil types and depths," indicating to the reader that there are distinctions in both the types of soil and their respective depths. Due to character limitations in the abstract, we cannot provide further elaboration on this topic in the Abstract, although it is included in the Materials and Methods.

2. The authors only mentioned that the experiment was conducted during the growing season (2014 and 2015); however, the authors should briefly describe the season, environmental conditions, soil texture, and water-holding capacity for the two trials.

Thank you very much for your review. The soil types are described in lines 99-100 and 115-116. We have added information about the environmental conditions in lines 100-102 and 116-118.

3. Authors should mention the initial physicochemical properties of each manure.

The nutrient concentrations of the fertilizers used are shown in lines 103-110 and 118-121.

4. Why did the authors only test cucumbers in August 2014 and peaches in August 2014 and 2015?

Since cucumber is an annual crop and would not normally be grown in the same plot year after year, we tested cucumbers for one year only. Peaches, on the other hand, are a perennial tree crop. In tree fruits, responses to fertilizer addition are often delayed. Therefore, multi-year experiments are essential.

5. Why did the authors pick cucumber and peaches as their test crops? One is an annual plant, whereas the other is a perennial plant.

We intentionally chose two very different crops growing on different soils to evaluate the impact of organic fertilizers on the soil microbial community under different conditions.

6. Authors should mention the changes in soil physicochemical properties after the addition of the manures in both experiments.

      This is an excellent suggestion for future studies. While our paper primarily focuses on the impact of fertilizers on soil microorganisms in the short-term, longer-term changes in soil physicochemical properties will be considered for future research.