Life Cycle Assessment for Soybean Supply Chain: A Case Study of State of Pará, Brazil

Round 1

Reviewer 1 Report (New Reviewer)

The abstract must present outstanding quantitative results, which are not currently shown.

Introduction. The introduction should include more background on LCA studies on global soybean production, now what is shown is scarce.

Line 82. They are not the only two types of LCA that can be applied, as stated, to correct it.

Materials and Methods. This section is incorrectly oriented, here the methodological stages of the LCA must be explained in detail, its description in general and how it was applied in the present study. However, now some of the sections are described as the very result of applying the methodology, therefore, this requires a thorough review and reorganization.

Lines 50 and 51. The correct citation of the consultation website for distances must be included and its complete information must be included in the references section.

Figure 3. This figure is confusing and little descriptive regarding the scope of this study, it is strongly recommended to improve it in a direct and organized way of the product system.

Software, Database and LCIA Method Used. In this section it is not clearly described whether field work was carried out in the study to obtain information for the LCI or if only data from external databases were used. This would detract from the originality of this study. It is also not mentioned if there were load allocations in the study.

Table 3. The information of the results should be organized by stages of the production system, which would help to understand the relevance of the inventory components.

Table 4. A relevant aspect of the environmental impacts of agricultural systems is the water footprint, therefore it is convenient to include it in the results.

Lines 235-268. The study highlights the results in transport, although it is relevant, it was not the only objective of the current LCA, for example, the energy consumption represented by said transport is not mentioned.

The discussion of results is again widely biased in the transport of soybeans, although it is not relevant to the main objective of the study as the title establishes. The discussion should be diversified according to what is shown in Table 4 and the other relevant stages of the product system.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report (New Reviewer)

Manuscript ID: agronomy-2337331

Title: Life Cycle Assessment for Soybean Supply Chain: A Case Study of State of Pará, Brazil

Major comments

1.     The manuscript must be prepared by following the Instruction for the Authors, please use the journal’s template and you can carefully check on this link https://www.mdpi.com/files/word-templates/agronomy-template.dot

2.     Subsection Aim of the Study (Line 135) must be moved to the last paragraph of the Section Introduction (please see the Manuscript Guideline in the Instruction for the Authors)

3.     In Line 179, the information is lacking. Please provide the source of Bradyrhizobium japonicum, does it a bio-fertilizer of a commercial product? or pure single isolate? Please provide the detail and describe briefly how the Author applied/inoculate the bacteria. Please provide the reference why the author recommends the inoculation of Bradyrhizobium japonicum

Minor comments

-       Line 102 please add the geographical coordinates of study areas

-       Line 128, delete “methodology”, this section is already for the Materials and Method

-       Line 129, please describe briefly the requirements and guidelines

-       Line 135 – 139, move this subsection to the last paragraph of the section Introduction

-       Line 140, Table 1. Transportation distances (km) and models, and port of shipment.

-       Line 158, please use SI units for the manuscript, it is a kilogram instead of kilogramme

-       Line 159, what is the cultivar of the GMO soybean?

-       Line 214, please describe the term “fresh matter”, does it mean the whole part of soybean plant? Or the pods? Or the Beans?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report (New Reviewer)

I believe that the authors have made the requested improvements since the previous revision.

Author Response

The stage of production system is the same of agricultural stage. So, for exemple, the farmers of this study used a pesticide called glyphosate during this agricultural stage. However, the database used in this software (open LCA) to process this informations also consider the impact he had upstream of agricultural stage (production system). As exemple, we can to cite the impact of production this pesticide, the storage of product, transport of product since the factory to the farm, pesticide residues in the Agroecosystem after use, etc. So, I consider unnecessary and impossible to divide the inputs (inventory components) due to all items of inventory were computed during your use, I.E. in the production system (agricultural stage).

Please check the links above with similar studies that applied the LCA in agricultural phase and described the tables without this division. I think that division is necessary in studies which involve diferent steps as agricultural stage and factory stages (for exemple, production of by products as soybean meal, biodiesel, and others).

Sustainability | Free Full-Text | Sustainable Viticulture: First Determination of the Environmental Footprint of Grapes (mdpi.com)

(6) (PDF) Life-cycle assessment of the soybean-sunflower production system in the Brazilian Cerrado (researchgate.net)

https://doi.org/10.2478/prolas-2022-0081

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

The position of the paragraph Aim of the Study (136) and Scope of the Study (154) should be separated from the Materials and Methods section by placing them immediately after the paragraph of the Introduction. Likewise, the position of table 1 (142) and table 2 (148).

101 The Materials and Methods paragraph needs to be reviewed and implemented. The methods used for the section dedicated to Crop Management and the one dedicated to transport should be divided and analyzed separately.

154 Crop Management: this part needs to be completed in greater detail. What were the selection criteria of the four companies? What method was used to obtain LCI information (survey, interview…)? The production processes and the field phases should be better highlighted to make the reading of the agronomic part clearer.

Furthermore, in this paragraph, a better description of the type of soil on which soybeans are grown should be made.

From line 174, there is no detail of the technical itineraries used in the farms, but generic data on fertilisation. Why this kind of choice?

194 Land Use Change. More details should be included in this paragraph, especially on how LUC data are used in the LCA of the companies under study.

202 Results: The results should be presented more clearly. Revise presentation of data in Table 3 (208)

Author Response

the letter with answers for reviewer 1.

Author Response File: Author Response.pdf

Reviewer 2 Report

This manuscript summarized information about increased environmental impact along with soybean supply chain and could be a good contribution to literature. This kind of  study is important as global climate changes dramatically and we need to prepare the situation. However, the manuscript is not in good form and contents are needed intensive modification. 

I provided detail editing, comments and suggestions in the attached manuscript and must be followed all that suggestions, references, citations etc before publication. I will be happy to reevaluate the paper after comments incorporation. 

Comments for author File: Comments.pdf

Author Response

the letter with answers for reviewer 2.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Despite the corrections made after the first revision, the article has deteriorated, lacking in the experimental model, in the description of the research aims and in the materials and methods.