Heavy Metal Pollution Assessment in the Agricultural Soils of Bonao, Dominican Republic

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article provides a detailed description of the study area, including its geographical location, climate, soil type, land use history, and water sources.

The methods for soil sample collection are clearly defined, including information on sampling depth, the number of samples collected, and sampling locations. The article mentions the use of reference standards to verify the accuracy of measurements, which is an important procedure to ensure data quality. The Results presents a comprehensive set of data related to physicochemical properties and heavy metal concentrations in the soil. This detailed data is essential for understanding the environmental conditions in the study area. However, the article mentions collecting background samples to establish a local reference point but does not provide information on how these background samples were collected or selected. This can affect the validity of the results. The Results and Discussion does not address potential sources of heavy metal contamination. Identifying these sources could provide valuable insights into environmental management and mitigation strategies. There is limited discussion of the reasons behind the spatial variations in heavy metal concentrations. In the article does not discuss the broader implications of the study's findings for local agriculture, human health, or the environment. This would provide a more comprehensive understanding of the significance of the results. For example, include the study of the concentration of the studied chemical elements that can be mobilized and that can in fact have an important impact in terms of agricultural production, public health and the environment.

Author Response

Manuscript ID: sustainability-2699469
Type of manuscript: Article
Title: Heavy Metals Pollution Assessment in Agricultural Soils of Bonao,
Dominican Republic
Authors: Natividad Miledy Alberto Then, Ramón Delanoy, Diana Rodríguez
Alberto, Ronaldo Méndez Hernández, Oscar Díaz Rizo, Lizaira Bello *

 The authors appreciate your valuable recommendations to enrich the content of the manuscript

Reviewer #1

The article provides a detailed description of the study area, including its geographical location, climate, soil type, land use history, and water sources.

The methods for soil sample collection are clearly defined, including information on sampling depth, the number of samples collected, and sampling locations. The article mentions the use of reference standards to verify the accuracy of measurements, which is an important procedure to ensure data quality. The Results presents a comprehensive set of data related to physicochemical properties and heavy metal concentrations in the soil. This detailed data is essential for understanding the environmental conditions in the study area.

Comments 1:  However, the article mentions collecting background samples to establish a local reference point but does not provide information on how these background samples were collected or selected. This can affect the validity of the results.

Response 1: In section 2.2, lines 85-87, we mentioned that three soil samples were collected in the positions BG01-BG03 at 50 cm deep to determine the local background. The data set has been incorporated into the supplementary material (Table S4).

Comments 2: The Results and Discussion does not address potential sources of heavy metal contamination. Identifying these sources could provide valuable insights into environmental management and mitigation strategies.

Response 2: In section 3.2, lines 229-233, we include the possible sources of heavy metal contamination in the studied area.

Comments 3:  There is limited discussion of the reasons behind the spatial variations in heavy metal concentrations.

Response 3: In section 3.3, lines 262-269, we made a more detailed discussion about the spatial variations of heavy metal concentrations.

Comments 4: In the article does not discuss the broader implications of the study's findings for local agriculture, human health, or the environment. This would provide a more comprehensive understanding of the significance of the results. For example, include the study of the concentration of the studied chemical elements that can be mobilized and that can in fact have an important impact in terms of agricultural production, public health and the environment.

Response 4: In the introduction section, lines 51-66, a paragraph was included about the importance of this study to contribute to sustainable agricultural production, promote soil management strategies for the production of healthy food, and reduce health and environmental risks.

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors, 

I reviewed this article "Heavy metals pollution assessment in agricultural soils of Bonao, Dominican Republic" which is an interesting article. I would like to accept this article after the suggested changes in addition to the other reviewer’s comments.

Introduction section: Needs some clarification about the rational of the study, where author listed a number on heavy metal contamination in the country, what was their focus? Did they look at Agricultural soil pollution, for certain crops or general. How does this study contribute to the knowledge using the case studies using the rice crop?  see many studies in the Asian region on this topic? Link this to the movement of pollutant, irrigation types?

Mitigation what else could be done, see the studies on how to reduce the heavy metal including Arsenic risk using a non-conventional irrigation, i.e., the sprinkler irrigation.

Methods section: Sampling strategy and provide a reference.

Physiochemical analysis? Of What Soil?

Results Section: While describing the results in the table provide, the details about the hydrogeology of the area, and sources of irrigation for the crop, that needs to be consistent for each sample, either groundwater or surface water.

Conclusion section: Needs a sentence of study implications.

I

Comments on the Quality of English Language

Acceptable 

Author Response

Manuscript ID: sustainability-2699469
Type of manuscript: Article
Title: Heavy Metals Pollution Assessment in Agricultural Soils of Bonao,
Dominican Republic
Authors: Natividad Miledy Alberto Then, Ramón Delanoy, Diana Rodríguez
Alberto, Ronaldo Méndez Hernández, Oscar Díaz Rizo, Lizaira Bello *

 The authors appreciate your valuable recommendations to enrich the content of the manuscript.

Reviewer #2

I reviewed this article "Heavy metals pollution assessment in agricultural soils of Bonao, Dominican Republic" which is an interesting article. I would like to accept this article after the suggested changes in addition to the other reviewer’s comments.

Comments 1:  Introduction section: Needs some clarification about the rational of the study, where author listed a number on heavy metal contamination in the country, what was their focus? Did they look at Agricultural soil pollution, for certain crops or general. How does this study contribute to the knowledge using the case studies using the rice crop?  see many studies in the Asian region on this topic? Link this to the movement of pollutant, irrigation types?

Response 1: In the introduction section, lines 51-66, information about the significance and contribution of this study to the Dominican Republic was included. We highlighted that there have been only a few studies conducted in the country on heavy metals in agricultural soils, such as rice, banana, and other cultivated soils. The references section includes several studies, including those from the Asian region.

Comments 2:  Mitigation what else could be done, see the studies on how to reduce the heavy metal including Arsenic risk using a non-conventional irrigation, i.e., the sprinkler irrigation.

Response 2: Mitigation was not one of the objectives of the study.

Comments 3:  Methods section: Sampling strategy and provide a reference.

Response 3: In section 2.2, lines 84-85, we mentioned the sampling strategy and included a reference.

Physiochemical analysis? Of What Soil?

Section 2.3, Our study was made in paddy soils.

Comments 4:  Results Section: While describing the results in the table provide, the details about the hydrogeology of the area, and sources of irrigation for the crop, that needs to be consistent for each sample, either groundwater or surface water.

Response 4: In section 2.2, line 77, we mentioned that the area is irrigated with superficial water supplied from the Yuna River.

Comments 5:  Conclusion section: Needs a sentence of study implications.

Response 5: In the conclusion section, lines 319-321, we included a paragraph highlighting the study implications.

 

Reviewer 3 Report

Comments and Suggestions for Authors

Dear Authors

In the work "Heavy metals pollution assessment in agricultural soils of Bonao, Dominican Republic", the authors assessed the concentration of some heavy metals in agricultural soils. The topic of the work fits well into the content of the Sustainability magazine. The study correctly selected and used statistical analyzes and indicators of heavy metal contamination. In my opinion, the purpose of the work was not properly or sufficiently specified. The objectives show that it was an analysis of the concentrations of pollution indicators. However, it follows that the authors did not properly highlight the research problem. In the work, the reader will not find information about the sources of pollution, i.e. the background, which poses a problem of control of the obtained results and lack of comparison. On the other hand, the authors calculated the PI and used the background. Whether the reference data - the background was used only based on literature or other data - should be provided.

The aspect of potential ecological risk was also not highlighted. The conclusions themselves contain information about the local background. However, it may also be insufficient for the reader.

I suggest analyzing the goals at work and specifying and supplementing them in accordance with the above comments.

Author Response

Manuscript ID: sustainability-2699469
Type of manuscript: Article
Title: Heavy Metals Pollution Assessment in Agricultural Soils of Bonao,
Dominican Republic
Authors: Natividad Miledy Alberto Then, Ramón Delanoy, Diana Rodríguez
Alberto, Ronaldo Méndez Hernández, Oscar Díaz Rizo, Lizaira Bello *

The authors appreciate your valuable recommendations to enrich the content of the manuscript.

Reviewer #3

In the work "Heavy metals pollution assessment in agricultural soils of Bonao, Dominican Republic", the authors assessed the concentration of some heavy metals in agricultural soils. The topic of the work fits well into the content of the Sustainability magazine. The study correctly selected and used statistical analyzes and indicators of heavy metal contamination.

Comments 1: In my opinion, the purpose of the work was not properly or sufficiently specified. The objectives show that it was an analysis of the concentrations of pollution indicators. However, it follows that the authors did not properly highlight the research problem. In the work, the reader will not find information about the sources of pollution, i.e. the background, which poses a problem of control of the obtained results and lack of comparison.

Response 1: In the introduction section, lines 51-66, information about the significance and contribution of this study to the Dominican Republic was included. 

In the discussion section, lines 233-240, we mentioned that there have been no studies on the status of heavy metal pollution in agricultural soils of the Dominican Republic to compare the results, for this reason, the maximum permitted levels of heavy metals in agricultural soils established by the FAO and the normal range of concentrations of heavy metals in agricultural soils introduced by Kabata-Pendias were used.

In section 3.2, lines 229-233, we include the possible sources of heavy metal contamination in the studied area.

Comments 2:  On the other hand, the authors calculated the PI and used the background. Whether the reference data - the background was used only based on literature or other data - should be provided.

Response 2: In section 2.2, lines 85-87, we mentioned that three soil samples were collected in the positions BG01-BG03 at 50 cm deep to determine the local background. The data set has been incorporated into the supplementary material (Table S4). The pollution index (PI) was calculated using the mean value of the local background as a reference value.

Comments 3:  The aspect of potential ecological risk was also not highlighted. The conclusions themselves contain information about the local background. However, it may also be insufficient for the reader.

Response 3: In the subtitle of section 3.4, the potential ecological risk index was included.

Comments 4: I suggest analyzing the goals at work and specifying and supplementing them in accordance with the above comments.

Response 4: Suggestions were accepted and included in the introduction, lines 51-66.

Reviewer 4 Report

Comments and Suggestions for Authors

This article needs a very serious revision. Detailed comments are provided below:

General comment 1: This study’s novelty should be highlighted more.

General comment 2: Objectives of the work should be made more clear.

1.      Introduction - requires supplementation, reference should be made to more recently published research.

2.      The introduction contains basic information. No new aspects are presented. The authors could better emphasize the novelty of the research carried out.

3.      Introduction - briefly explain the motivation for undertaking this research, its relevance and originality, where it fits into the development of the field, and why it should be of interest to sustainability readers.

4.      The weaknesses and limitations of this study compared to other studies should be considered.

5.      Section material and methods: were samples collected only once?

6.      Section material and methods: The levels of these elements in the soil were below the detection limits…”- Add LOD and LOQ.

7.      Table 1 and Table 2- adjust the font and its size to sustainability requirements.

8.      Line 256-264  and Line 302-315 - You should remove all blank lines as follows.

9.      Highlight the main difficulties and challenges and your original achievements in overcoming.

10.   Results and Discussion - It is important to check that the writing text clearly expresses and explains each idea and result obtained.

11.   The conclusions needs improvement - highlight the most important findings and identify the added value of the main finding.

12.   Conclusions should state the main findings. Conclusions - consider adding numerical results to this section.

Author Response

Manuscript ID: sustainability-2699469
Type of manuscript: Article
Title: Heavy Metals Pollution Assessment in Agricultural Soils of Bonao,
Dominican Republic
Authors: Natividad Miledy Alberto Then, Ramón Delanoy, Diana Rodríguez
Alberto, Ronaldo Méndez Hernández, Oscar Díaz Rizo, Lizaira Bello *

The authors appreciate your valuable recommendations to enrich the content of the manuscript.

Reviewer #4

Comments 1:  This article needs a very serious revision. Detailed comments are provided below:

General comment 1: This study’s novelty should be highlighted more.

General comment 2: Objectives of the work should be made more clear.

• Introduction - requires supplementation, reference should be made to more recently published research.
• The introduction contains basic information. No new aspects are presented. The authors could better emphasize the novelty of the research carried out.
• Introduction - briefly explain the motivation for undertaking this research, its relevance and originality, where it fits into the development of the field, and why it should be of interest to sustainability readers.

Response 1: In the introduction section, lines 51-66, information about the significance and contribution of this study to the Dominican Republic was included. We highlighted that there have been only a few studies conducted in the country on heavy metals in agricultural soils, such as rice, banana, and other cultivated soils. The references section includes several studies, including those from the Asian region.

Comments 2:  The weaknesses and limitations of this study compared to other studies should be considered. Highlight the main difficulties and challenges and your original achievements in overcoming.

Response 2: In the discussion section 3.2, lines 233-241, we mentioned that there are no official guidelines for healthy concentrations of metals in agricultural soils in the Dominican Republic, nor has a baseline been established for making comparisons. For this reason, the comparisons were made with the maximum heavy metals concentration values for healthy agricultural soil, according to the Food and Agriculture Organization (FAO), and the normal range of concentrations of heavy metals in agricultural soils introduced by Kabata-Pendias.

Another limitation of our study is that the analytical technique we used was unable to detect the presence of Hg and Cd, these two metals are highly toxic and pose a significant environmental risk. Therefore, in the conclusion section, we suggested that future studies employ a more sensitive analytical technique to analyze these metals.

Comments 3:  Section material and methods: were samples collected only once?

Response 3: In the Caribbean region, two seasons are distinguished: the dry season and the rainy season. Soil samples were collected during the dry season due to the soil surface is more stable. Furthermore, the seasonal variation was not included as part of the objectives of this study.

Comments 4:  Section material and methods: The levels of these elements in the soil were below the detection limits…”- Add LOD and LOQ.

Response 4: The detection limits (DL) and Quantification Limit (QL) for each element of the EDXRF technique were included in supplementary materials (Table S1).

Comments 5:  Table 1 and Table 2- adjust the font and its size to sustainability requirements. Line 256-264  and Line 302-315 - You should remove all blank lines as follows.

Response 5: Suggestions were made.

Comments 6:  Results and Discussion - It is important to check that the writing text clearly expresses and explains each idea and result obtained.

 Response 6: Suggestions were included.

Comments 7:  The conclusions needs improvement - highlight the most important findings and identify the added value of the main finding.

Response 7: Conclusions should state the main findings. Conclusions - consider adding numerical results to this section.

The conclusions mentioned the heavy metals present in studied soils, highlighting the pollution level of these elements according to the calculated indexes, the distribution patterns of the elements, and the potential ecological risk index.

In the conclusion section, lines 315-322, we included a paragraph highlighting the study implications.

 

 

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

I would like to thank the Authors for taking into account their comments, suggestions and explanations.

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Reviewer 4 Report

Comments and Suggestions for Authors

The comments are addressed properly and necessary corrections have been done.