A Perspective on Four Emerging Threats to Sustainability and Sustainable Development
Round 1
Reviewer 1 Report
This is a thoughtful analysis of an issue of great and growing importance. The facts that the authors are from Africa and that the paper adopts an African perspective make it a particularly welcome contribution to the debate regarding a suite of major social issues.
I think there is a publishable paper here. But I also think the impact of the paper could be enhanced greatly by restructuring the argument somewhat. Let me explain.
The four issues addressed are clearly important. But they are by no means the only important issues on the policy agenda today.
The critical insight of this paper is that plastic pollution is not only an issue of rapidly growing concern but that taking action to address the plastics problem also can contribute significantly to dealing with the problems of unemployment, affordable housing, and climate change.
Rather than discussing the four problems one at a time, it would help to consider opportunities for addressing the plastics problem first and then to show in some detail how tackling this problem could contribute at the same time to increasing employment, producing affordable housing, and reducing emissions of GHGs. Exploring these links in some detail rather than leaving them to a few cursory paragraphs at the end of the paper would yield a much stronger argument.
Author Response
Response to Reviewer 1 Comments
Kindly note that extensive editing of the English language has been completed by Busy Bee Editing.
Point 1: This is a thoughtful analysis of an issue of great and growing importance. The facts that the authors are from Africa and that the paper adopts an African perspective make it a particularly welcome contribution to the debate regarding a suite of major social issues.
Response 1: Noted, these four crises are currently emerging in South Africa and are worthy of attention.
Point 2: I think there is a publishable paper here. But I also think the impact of the paper could be enhanced greatly by restructuring the argument somewhat. Let me explain.
The four issues addressed are clearly important. But they are by no means the only important issues on the policy agenda today.
Response 2: Noted. Arguments have been restructured. However, the focus is on the four emerging crises in South Africa currently.
Point 3: The critical insight of this paper is that plastic pollution is not only an issue of rapidly growing concern but that taking action to address the plastics problem also can contribute significantly to dealing with the problems of unemployment, affordable housing, and climate change.
Response 3: Noted. There are many solutions included under each emerging threat. However, recycling is the proposed action to manufacture plastic sand bricks which will contribute significantly to the four crises. This has been demonstrated in the paper with “additional information” provided.
Point 4: Rather than discussing the four problems one at a time, it would help to consider opportunities for addressing the plastics problem first and then to show in some detail how tackling this problem could contribute at the same time to increasing employment, producing affordable housing, and reducing emissions of GHGs. Exploring these links in some detail rather than leaving them to a few cursory paragraphs at the end of the paper would yield a much stronger argument.
Response 4: The opportunities/ solutions for addressing the plastic pollution problem have been included. Figure 5 is used to demonstrate the opportunity of recycling 2 tonnes of plastic from the environment could contribute significantly to unemployment, affordable housing, and climate change has been included.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The article entitled “A perspective on four emerging threats to sustainability and sustainable development” it is divided into too many subsections and it is difficult to follow.
Figure 2 must be redone. Please delete the numbers inside the figure, can't see these numbers well.
Figure 4 can be modified; it is not very clear.
Plastic bricks manufacturing process is not described. Please see:
- Study of Plastic Bricks Made from Waste Plastic, International Research Journal of Engineering and Technology;
- Green-efficient masonry bricks produced from scrap plastic waste and foundry sand, Case Studies in Construction Materials;
- Marine plastic pollution and affordable housing challenge: Shredded waste plastic stabilized soil for producing compressed earth bricks, Case Studies in Construction Materials
- A review on utilization of plastic waste materials in bricks manufacturing process/ https://doi.org/10.1016/j.matpr.2021.04.337
Which type of plastic can be used for bricks production? All plastics are suitable for brick production? There are no differences?
Author Response
Response to Reviewer 2 Comments
Kindly note that extensive editing of the English language has been completed by Busy Bee Editing.
Point 1: The article entitled “A perspective on four emerging threats to sustainability and sustainable development” it is divided into too many subsections and it is difficult to follow.
Response 1: Noted. The last paragraph in the introduction explains the different sections of the paper. Each sub-section has been introduced.
Point 2: Figure 2 must be redone. Please delete the numbers inside the figure, can't see these numbers well.
Response 2: Figure 2 has been redrawn and figures have been removed.
Point 3: Figure 4 can be modified; it is not very clear.
Response 3: Figure 4 has been redrawn.
Point 4: Plastic bricks manufacturing process is not described.
Response 4: The manufacturing process of the plastic sand brick has been described in figure 9.
Point 5: Please see:
- Study of Plastic Bricks Made from Waste Plastic, International Research Journal of Engineering and Technology;
- Green-efficient masonry bricks produced from scrap plastic waste and foundry sand, Case Studies in Construction Materials;
- Marine plastic pollution and affordable housing challenge: Shredded waste plastic stabilized soil for producing compressed earth bricks, Case Studies in Construction Materials
- A review on utilization of plastic waste materials in bricks manufacturing process/ https://doi.org/10.1016/j.matpr.2021.04.337
Response 5: All the above articles have been consulted.
Point 6: Which type of plastic can be used for bricks production? All plastics are suitable for brick production? There are no differences?
Response 6: Types of plastic waste used for the manufacture of plastic sand brick has been explained and a table showing literature with the type of plastic used to manufacture plastic sand bricks has been included.
Author Response File: Author Response.pdf
Reviewer 3 Report
Manuscript ID: earth-1989540
Title: A perspective on four emerging threats to sustainability and sustainable development
This paper examines four emerging global crises that has been identified (plastic pollution, unemployment, shortage of affordable housing and climate change) as a threat to sustainability. Results show that the manufacturing of plastic sand bricks and other building products from waste plastic is proposed to reduce plastic pollution, unemployment, shortage of affordable housing, and climate change.
I appreciate the opportunity to review the proposed article and hope that my considerations will help to improve the work. My detailed comments are as follows:
Abstract: The abstract section should clearly mention the objective, methods, and concise results in sequence. Revise accordingly
Introduction: In the introduction section, research objectives are missing. Clarify the background, objectives, research gaps, and innovations in this section. Further introduction section is too short as not enough literature on environmental threats is included. Add more appropriate literature in this section or add an additional section of literature review to give detailed background of the study.
Add subsections carefully of four emerging threats to sustainability and sustainable development which you discussed in detail.
Add more detailed solutions in each treat to sustainable development. Further, explain the process of plastic conversion into bricks. Is this procedure pollution free? Explain briefly.
Discuss solutions in detail and mention the innovative outcome. Further solutions should be backed with appropriate literature.
Conclusion: Add limitations and future research ideas in the conclusion section
Avoid grammatical and typo errors, and revise the manuscripts for these two concerns
Author Response
Response to Reviewer 3 Comments
Kindly note that extensive editing of the English language has been completed by Busy Bee Editing.
Point 1: I appreciate the opportunity to review the proposed article and hope that my considerations will help to improve the work.
Response 1: Noted. Review comments were valuable.
Point 2: My detailed comments are as follows:
Abstract: The abstract section should clearly mention the objective, methods, and concise results in sequence. Revise accordingly
Response 2: The abstract has been revised accordingly.
Point 3: Introduction: In the introduction section, research objectives are missing. Clarify the background, objectives, research gaps, and innovations in this section. Further introduction section is too short as not enough literature on environmental threats is included. Add more appropriate literature in this section or add an additional section of literature review to give detailed background of the study.
Response 3: The introduction has been revised accordingly.
Point 4: Add subsections carefully of four emerging threats to sustainability and sustainable development which you discussed in detail.
Response 4: The flow of the subsections has been checked and adjusted.
Point 5: Add more detailed solutions in each treat to sustainable development.
Response 5: The solutions under each threat have been included.
Point 6: Further, explain the process of plastic conversion into bricks. Is this procedure pollution free? Explain briefly.
Response 6: The process of plastic conversion to plastic sand bricks has been diagrammatically explained with descriptions in figure 9.
Point 7: Discuss solutions in detail and mention the innovative outcome. Further solutions should be backed with appropriate literature.
Response 7: The opportunities/solutions for each emerging threat have been included. However, the review paper focuses on one opportunity in detail i.e. the feasibility of using plastic waste to manufacture bricks (as a solution) to address all four crises.
Point 8: Conclusion: Add limitations and future research ideas in the conclusion section
Response 8: Point 8 has been addressed and included.
Point 9:Avoid grammatical and typo errors, and revise the manuscripts for these two concerns
Response 9: Kindly note that extensive editing of the English language and style has been completed by Busy Bee Editing.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
This is a revised version of a paper I reviewed in its original form.
The authors have taken my suggestions seriously and worked hard to revise the paper constructively. The new version seems considerably stronger to me, and I think it is publishable.
I do have one suggestion that I hope the authors will think about it preparing a final text for publication. The idea of using recycled plastic in the production of sand bricks is appealing. It may well be that this initiative can make a difference as well in addressing the problems of unemployment, affordable housing, and climate change.
BUT it would help to offer at least some preliminary evidence regarding how these desirable side effects would work. For example, how would the manufacture of sand bricks generate employment opportunities? How can the bricks be used in the construction of affordable housing? Would these desirable side effects occur naturally? Or would it be necessary to introduce policy measures to maximize the achievement of these side effects?
Author Response
Response to Reviewer 1 Comments
Kindly note that extensive editing of the English language has been completed by Busy Bee Editing.
This is a revised version of a paper I reviewed in its original form.
The authors have taken my suggestions seriously and worked hard to revise the paper constructively. The new version seems considerably stronger to me, and I think it is publishable.
I do have one suggestion that I hope the authors will think about it preparing a final text for publication. The idea of using recycled plastic in the production of sand bricks is appealing. It may well be that this initiative can make a difference as well in addressing the problems of unemployment, affordable housing, and climate change.
Point 1: BUT it would help to offer at least some preliminary evidence regarding how these desirable side effects would work. For example, how would the manufacture of sand bricks generate employment opportunities? How can the bricks be used in the construction of affordable housing? Would these desirable side effects occur naturally? Or would it be necessary to introduce policy measures to maximize the achievement of these side effects?
Response 1: The suggestion made by the reviewer is a thought-provoking one. The manufacturing of plastic sand bricks is a totally new innovation in the construction industry in South Africa. The manufacturing of plastic sand bricks to address the four crises will not take place naturally or automatically but needs government intervention. Recently, the South African government designed guidelines whereby waste pickers have been incorporated into the waste management system and into the formal industry. This is predicted to have positive ramifications for our economy and all sectors of society. Therefore, the extent of how the plastic sand brick will generate employment and the potential/feasibility of using plastic sand brick to construct affordable houses has been demonstrated in the case analysis in the review paper.
Reviewer 2 Report
The authors have considerably improved the manuscript.
Author Response
Response to Reviewer 2 Comments
Point 1: The authors have considerably improved the manuscript
Response 1: The authors appreciate the positive feedback.
