Testing and EDEM Simulation Analysis of Material Properties of Small Vegetable Seeds for Sustainable Seeding Process

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This research merely lacks innovation, but it is comprehensive. It has conducted some measurements that have never been done before. Although the work is small, it is worthy of recognition.

Author Response

We sincerely appreciate the reviewers taking time out of their busy schedules to review this manuscript. Your professional and detailed comments not only point out the deficiencies and omissions in the paper but also provide us with highly valuable revision ideas and research directions, which are crucial for improving the academic quality and rigor of the manuscript. We will carefully study each suggestion, sort them out one by one, and conduct in-depth revisions and improvements, striving to reach a higher level in terms of content depth, logical structure, and detailed presentation. Once again, we would like to express our most sincere gratitude to all reviewers for their careful guidance and selfless help!

Reviewer 2 Report

Comments and Suggestions for Authors

1. Change the Chinese in Figure 11 to English, and the legend text in Figure 12 is unclear.
2. What does' seed rope bracing machines' mean for line 244 and how does it relate to the article.
3. In Figure 3, when comparing the sliding friction angle and natural angle of repose, although the differences between nearly spherical and elongated seeds are pointed out, the reasons for the differences are not specifically analyzed.
4. When simulating parameters in EDEM (such as density, Poisson's ratio, etc. in Tables 7 and 8), the basis for determining these parameters was not specified.
5. When describing various experimental measurements (such as 1000 particle weight, sliding friction angle, etc.) in the text, the number of repetitions for some experiments is not clear enough.

Author Response

Response to Reviewer 2 Comments

 

Q1: Change the Chinese in Figure 11 to English, and the legend text in Figure 12 is unclear.
Response: The image has been modified.

Q2: What does' seed rope bracing machines' mean for line 244 and how does it relate to the article.

Response: Seed rope directing-seed technology is a precision sowing technique that can mix and arrange multiple varieties according to specific grain spacing and number, suitable for precision breeding and variety comparison research. In the preliminary research, it was found that manual rope breaking is required when seeding ropes and turning around at the boundary of the plot, which affects efficiency and accuracy.

To solve the above problems, a quantitative and directional device actuator was developed. The material of the roller for the seed rope transmission is rubber, which can effectively reduce mechanical damage to the sprouts in the seed rope, as shown in Figure 1.

The mechanical properties of the seed rope material and the integrity of the wrapped seeds are critical factors that influence the growth and development of the plants root system, which in turn is a key determinant for the optimization of the seed rope automated quantitative mechanism. This paper employed uniaxial tensile testing to investigate the mechanical properties and tensile failure characteristics of seed ropes across various materials, seed wrapping techniques, and seed soaking methods.

 

Figure 1 Automated quantitative mechanism

  

   Figure 2 Field sowing

 

Q3: In Figure 3, when comparing the sliding friction angle and natural angle of repose, although the differences between nearly spherical and elongated seeds are pointed out, the reasons for the differences are not specifically analyzed.

Response: It can be clearly seen from Figure 2 that there are specific differences in the three-axis dimensions between nearly spherical seeds and elongated flat seeds

Q4: When simulating parameters in EDEM (such as density, Poisson's ratio, etc. in Tables 7 and 8), the basis for determining these parameters was not specified.

Response: The seed density parameters in Tables 7 and 8 refer to the measurement values of similar seeds in [18-25], while Poisson's ratio and shear modulus are combined with previous laboratory test results of similar seeds

Q5: When describing various experimental measurements (such as 1000 particle weight, sliding friction angle, etc.) in the text, the number of repetitions for some experiments is not clear enough.

Response: Repeat three times and take the average

 

 

 

We would like to thank you for your professional review work,constructive comments,and valuable suggestions on our manuscript.

 

 

 

 

 

 

 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Line 16 and many following lines: Add a space behind a . if it seperates two sentences

Line 24: Resolve the abbreviation EDEM here

Chapter "Materials and Methods" - Add images of seeds, at least of 4 typical variations as shown in Fig. 2
Show an overview table for the 16 varieties here and use abbreviatons in the following text - this will make the following tables Tab. 2, 3, ... much clearer.

Line 130: Did you consider to measure length and width using shape measeurement by image analysis? Although the thickness dimension is not available, the measurement could be faster, and comprise more seeds, and the thickness information could be achieved by caliper measurements on a smaller amount of samples.

Fig. 2: Add a table of the numerical results. 
"Average" is the arithmetic mean, and the whiskers show the standard deviation? Do the frequency distributions of the dimensions show (more or less) a Gaussian distribution? Show some of these distributions.

Line 172: Is this Chinese standard similar or in accordance with similar international standards like e.g. ISO 665 or the ISTA Handbook on Moisture Determination? If not, why did you use a local standard?

Line 210: What type of plastic?

Line 212: How did you determine the level 90%?

Line 264: Regarding the experiments on the sliding friction angles - does the surface material of the petri dish affect the "natural" repose angle? If not, explain why.

Fig. 5: Explain the letters a b c d - do you mean seed types?

3.3.2 ... seed particle models: Do the Models consider also surface roughness of the particles? I guess that it is not the same if the particles are smooth or rough.

Fig. 7: The quality of the screenshots is insufficient.  I suggest to use only the diagrams with a better resolution and to explain the parameters on the left seperately.

Fig. 8 right: Numbers inside the angle are not clearly visible.

Fig. 9: Same remark as for Fig. 7

Line 384: Explain the significant difference between the repose angles from simulation and from measurement.

Fig. 10 right: Parameter descriptions too small, not clearly visible.

Fig. 11: Translate the Chinese descriptions.

Fig. 12: Letters in the legend are too small.

Line 439: Do you mean "discussion" ?

Line 460: What do you mean by "plastic"?

 

 

 

 

 

Author Response

Response to Reviewer 3 Comments

Q1: Line 16 and many following lines: Add a space behind a . if it seperates two sentences.
Response: Thank you for highlighting this formatting issue. We have carefully reviewed the manuscript and added a space after all full stops (.) that separate sentences throughout the text . This revision has been systematically applied to all relevant lines using Word's "Find and Replace" function with wildcard checks to ensure accuracy. We appreciate your meticulous attention to detail.

Q2: Resolve the abbreviation EDEM here.
Response: Thank you for this important reminder. We have now resolved the abbreviation "EDEM" at its first occurrence in the main text (Line 64-65) by explicitly defining it as: "Engineering Discrete Element Method (EDEM)" All subsequent mentions consistently use "EDEM" without redefinition.

Q3: Chapter "Materials and Methods" - Add images of seeds, at least of 4 typical variations as shown in Fig. 2.Show an overview table for the 16 varieties here and use abbreviatons in the following text - this will make the following tables Tab. 2, 3, ... much clearer.
Response: We have added pictures and a table of abbreviations for seed names,And the chart and order have been readjusted.

Q4: Line 130: Did you consider to measure length and width using shape measeurement by image analysis? Although the thickness dimension is not available, the measurement could be faster, and comprise more seeds, and the thickness information could be achieved by caliper measurements on a smaller amount of samples.
Response: For the small sample size experimental needs of this study, we used vernier calipers to accurately measure the length, width, and thickness of the seeds. Given the importance of measurement efficiency for large-sample studies, we are actively considering the use of an automated shape measurement method based on image analysis for future experiments. This method can significantly increase the speed of seed length and width measurements, allowing for larger sample sizes to be processed. While image analysis is often difficult to accurately obtain thickness information, thickness data can be supplemented by vernier caliper measurements on a representative subset of samples. This combined approach promises to significantly increase experimental throughput while ensuring data accuracy in key dimensions.

Q5: Fig. 2: Add a table of the numerical results. "Average" is the arithmetic mean, and the whiskers show the standard deviation? Do the frequency distributions of the dimensions show (more or less) a Gaussian distribution? Show some of these distributions.
Response: In this analysis, the term “average” refers specifically to the arithmetic mean. Regarding the boxplots, the whiskers represent the standard deviation. Furthermore, the frequency distributions of the seed dimensions (length and width) generally exhibit a shape that is more or less Gaussian (normal).

Q6:Line 172: Is this Chinese standard similar or in accordance with similar international standards like e.g. ISO 665 or the ISTA Handbook on Moisture Determination? If not, why did you use a local standard?
Response: The seed testing standard GB/T 3543.6-1995 adopted in this study carries the globally recognized UDC 633.1/.8.001.4:631.531, which categorizes it as: “Technical standards for seed treatment in cereal and industrial crops” within the international classification system. This signifies its inherent alignment with global agricultural standardization frameworks. Critically, this standard:Maintains technical equivalence with the ISTA International Rules (1993 Edition) in core methodologies; Incorporates region-specific adaptations through: Localized crop examples , Climate-adjusted testing parameters ; Holds regulatory primacy as China’s compulsory certification standard, ensuring legal compliance for domestically sourced specimens. While fully comparable with international benchmarks, GB/T 3543.6-1995 provides enhanced ecological validity for studies focused on regional crop germplasm. For cross-regional validation, ISTA-compliant replication is recommended in future work.
Q7:Line 210: What type of plastic?
Response:It made of Polyvinyl chloride (PVC).

 

Q8:Line 212: How did you determine the level 90%?
Response: The 90% threshold was determined through empirical gravimetric calibration. Specifically: Total Sample Weight: A standardized 10g seed lot was used for all tests; Progressive Measurement: The weight of seeds passing through the testing apparatus was recorded at 1-second intervals; Threshold Calculation: The timepoint at which 9.0±0.1g (90% of 10g) had passed was identified as the functional completion point of seed flow. This gravimetric approach eliminates subjectivity in visual assessment and ensures replicability across trials.
Q9:Line 264: Regarding the experiments on the sliding friction angles - does the surface material of the petri dish affect the "natural" repose angle? If not, explain why.
Response: We sincerely thank the reviewer for raising this important point. The surface material of the petri dish does indeed affect the natural repose angle measurement, as interfacial friction between seeds and the substrate directly influences particle mobility and stacking behavior. In our study, all repose angle measurements were consistently conducted using standardized glass petri dishes. While substrate properties , we emphasize that: Cross-sample comparability is preserved since identical contact surfaces were used for all seed varieties; Methodological consistency eliminates inter-material variability as a confounding factor. In order to improve the clarity, we will revise the manuscript and mark the background colour as blue, which clearly states: "In each measurement, a glass petri dish was used as the substrate to ensure a smooth and uniform base, minimizing the influence of substrate effects on the seed pile morphology. " We acknowledge that absolute repose angles may differ if measured on other surfaces (e.g., steel or textured polymers), but our conclusions regarding relative differences between seed types remain robust under controlled conditions.

Q10:Fig. 5: Explain the letters a b c d - do you mean seed types?
Response:We sincerely appreciate the reviewer's valuable observation regarding the labeling in Figure 5. We apologize for the oversight in not explicitly defining the sub-indicators "a, b, c, and d" within the manuscript text. The letters "a", "b", "c", and "d" in Figure 5 represent the four specific cultivars tested for each seed type listed in Table 6 .We thank the reviewer for highlighting this need for clarification. In the revised manuscript, we will add a detailed explanation of these labels within the caption of Figure 5 and/or the relevant Results section text. Furthermore, the background of these labels ("a", "b", "c", "d") in Figure 5 will be highlighted in blue to ensure they are easily identifiable during the review process.

Q11:3.3.2 ... seed particle models: Do the Models consider also surface roughness of the particles? I guess that it is not the same if the particles are smooth or rough.
Response: We have already taken into account the addition of static friction coefficient and rolling friction coefficient in the boundary conditions.

Q12:Fig. 7: The quality of the screenshots is insufficient.  I suggest to use only the diagrams with a better resolution and to explain the parameters on the left seperately.
Response: We sincerely thank the reviewer for the valuable suggestion regarding the image quality in Figure 8. We acknowledge that the original screenshots did not meet the required resolution for clear visualization. In direct response to the reviewer’s comments, we have implemented the following improvements: 1.The original screenshots have been replaced with new, high-resolution diagrams to ensure optimal clarity and readability. 2.As suggested, all parameters previously indicated on the left side of the diagrams have now been explicitly defined and compiled in a Table 7. This provides a clear and separate reference for readers. These revisions significantly enhance the figure’s quality and the accessibility of the presented data. The updated Figure 7 and explanatory Table 7 are now included in the revised manuscript.We greatly appreciate the reviewer’s insightful feedback, which has substantially improved the presentation of our results.

 

Q13:Fig. 8 right: Numbers inside the angle are not clearly visible.
Response: We thank the reviewer for highlighting the visibility issue in Figure 9 (right panel). The original numerical values have now been bolded for enhanced clarity, and the image resolution has been optimized. These adjustments ensure all angle labels are clearly visible in the revised manuscript.

 

 

Q14:Fig. 9: Same remark as for Fig. 7
Response: We sincerely appreciate the reviewer's constructive feedback regarding the visual clarity of Figure 10. We acknowledge that the original screenshots did not meet the required quality standards for detailed interpretation. In direct response to the reviewer's suggestions, we have implemented the following critical improvements: 1.The original screenshots have been completely replaced with professionally rendered, high-resolution diagrams to ensure optimal clarity. 2.All parameters originally displayed on the left side of the diagrams have been systematically compiled and explained in a dedicated Table 8. These modifications significantly enhance data accessibility and visual precision. The revised Figure 10 and Table 9 are now incorporated in the updated manuscript. We are grateful for the reviewer's insightful recommendation, which has substantially strengthened the presentation quality of our results.
Q15:Line 384: Explain the significant difference between the repose angles from simulation and from measurement.
Response: The instructions have been added in the corresponding position.

Q16:Fig. 10 right: Parameter descriptions too small, not clearly visible.
Response: We sincerely thank the reviewer for noting the legibility issue in Figure 10 (right panel). We regret that PDF compression reduced label clarity in the submission file. Please be assured the original high-resolution images fully meet journal standards. We will: 1.Provide uncompressed files during production. 2.Work with editors to ensure perfect clarity in final proofs. We appreciate your vigilance in enhancing our presentation quality.
Q17:Fig. 11: Translate the Chinese descriptions.
Response: We sincerely thank the reviewer for highlighting the need for translation in Figure 11. All Chinese descriptions have now been replaced with English labels to ensure international readability. The revised figure is incorporated in the updated manuscript. We appreciate this valuable suggestion for improving our presentation clarity.

 

Q18:Fig. 12: Letters in the legend are too small.
Response:We sincerely appreciate the reviewer's observation regarding the legend labels in Figure 12. To address the visibility concern: 1.All descriptive labels have been replaced with standard alphanumeric markers (a, b, c...). 2.A comprehensive reference key for these markers is now provided in Table 9. 3.This dual approach ensures both visual clarity and full parameter traceability. The revised Figure 12 and explanatory Table 9 appear in Section [3.4.1] of the updated manuscript. We thank the reviewer for this valuable suggestion to improve our data presentation.

 

 

Q19:Line 439: Do you mean "discussion" ?
Response: We sincerely thank the reviewer for identifying the typographical error in Line 439. The term "discussion" has now been correctly spelled throughout the manuscript. This correction appears in the revised version. We appreciate your meticulous proofreading.

Q20:Line 460: What do you mean by "plastic"?
Response: We thank the reviewer for requesting clarification on "plastic". In this context, "plastic" specifically denotes the engineering polymer material selected for fabricating seed box guide components. 

We would like to thank you for your professional review work,constructive comments,and valuable suggestions on our manuscript.

 

 

 

 

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

1. Redo the figures and graphs, make them more legible.
2. How does the shape of seeds (spherical vs. elongated) influence their weight, dimensions, flowability and overall sowing performance?
3. Why do plastic plates reduce friction more than other materials, and how does this parameter optimize the design of seed guides?
4. What physical parameters (shape, mass, friction) need to be precisely defined in EDEM simulations to accurately model the tribological behavior of seeds?
5. How can the accuracy of EDEM models be improved to reduce the discrepancy between simulated and measured angles of repose (e.g. 2.86° difference)?
6. What is the influence of particle-particle and particle-surface interactions in the simulation of angles of repose, and how do these affect the results?
7. To what extent can the natural angle of repose be used as a reliable criterion for designing hoppers and preventing blockages in seeding equipment?
8. How does the cross-validation of simulated and experimental EDEM results enhance the predictive design of agricultural equipment?
9. What experimental conditions need to be rigorously standardized to ensure valid comparisons with numerical simulations?
10. What are the current limitations of pelleted seeds in terms of germination?

11. Enrich your work with bibliographical references.

Author Response

Response to Reviewer 4 Comments

Q1：Redo the figures and graphs, make them more legible.
Response: Thank you for your valuable feedback regarding the clarity of our figures. We sincerely apologize for any inconvenience caused by the suboptimal image quality in the original submission. All figures and graphs have been comprehensively redesigned to enhance legibility. We appreciate your guidance in elevating the visual communication of our research. Should further adjustments be needed, we will promptly implement them.

Q2：How does the shape of seeds (spherical vs. elongated) influence their weight, dimensions, flowability and overall sowing performance?
Response: The shape of seeds can affect their test weight. The closer they are to a sphere, the better their fluidity, making it easier to separate and count them during the sowing process, thus facilitating single-seed sowing.

Q3: Why do plastic plates reduce friction more than other materials, and how does this parameter optimize the design of seed guides?
Response: The surface of the plastic board is smooth, and the flowability of the seed group is better. The seed group is not easily arched and lifted, so compared to other materials, the angle of inclination on the side of the plastic seed box does not need to be very large, which can accommodate more seeds.

Q4: What physical parameters (shape, mass, friction) need to be precisely defined in EDEM simulations to accurately model the tribological behavior of seeds?
Response: To accurately model the tribological behavior of seeds in EDEM simulations, the following key physical parameters must be precisely defined: For shape, appropriate geometric representation methods (e.g., multi-sphere clusters, CAD models) based on seed morphology (e.g., ellipsoidal, irregular) are required, along with dimensional metrics (length, width, thickness, equivalent diameter) and surface texture. In terms of mass and density, seed density (accounting for moisture effects) and particle size distribution (PSD) are critical to ensure accurate mass calculations and realistic interaction replication. Tribological parameters include inter-particle and particle-wall sliding/rolling friction coefficients. Contact mechanics parameters encompass Young’s modulus, Poisson’s ratio, and normal/tangential restitution coefficients, which influence contact deformation and energy loss. Adhesion-related parameters such as surface energy or liquid bridge properties should be considered when necessary. These parameters must be experimentally determined for specific seed species and environmental conditions.

Q5: How can the accuracy of EDEM models be improved to reduce the discrepancy between simulated and measured angles of repose (e.g. 2.86° difference)?
Response: To reduce the discrepancy between simulated and measured angles of repose (e.g., 2.86°) in EDEM models, multiple optimizations are needed: precisely measure and iteratively adjust tribological and contact parameters such as inter-particle/particle-wall sliding/rolling friction coefficients and Young’s modulus; replace simplified shapes with high-fidelity geometric models (multi-sphere clusters, CAD-imported models) to capture real seed morphology; calibrate boundary conditions (container geometry, wall properties, particle release methods) to match experiments; optimize simulation parameters (time step, particle count); systematically calibrate coupled parameters using methods like response surface methodology; and validate against reliable measured data to minimize deviations.

Q6: What is the influence of particle-particle and particle-surface interactions in the simulation of angles of repose, and how do these affect the results?
Response: Particle-particle and particle-surface interactions are core factors influencing the simulation of angles of repose. Sliding and rolling friction between particles determine the resistance to their relative movement: higher friction coefficients make particles less likely to slide or roll, leading to steeper堆积 angles when piled up. Additionally, the interlocking effect of particle shapes (such as the uneven structures of non-spherical particles) further enhances this resistance, improving the stability of the pile. Meanwhile, the frictional interaction between particles and container surfaces is also crucial: higher particle-wall friction restricts the sliding of particles along the wall, causing particles at the edges to pile up more steeply and increasing the overall angle of repose; conversely, lower wall friction allows particles to spread more easily, resulting in a smaller angle. These interactions collectively balance the downward movement tendency of particles caused by gravity and the resistance generated by friction. Discrepancies between the parameter settings and reality (such as inaccurate friction coefficients or excessive simplification of shapes) will directly lead to differences between the simulated angle of repose and the measured value.

Q7: To what extent can the natural angle of repose be used as a reliable criterion for designing hoppers and preventing blockages in seeding equipment?
Response: The natural angle of repose is a useful foundational criterion for designing hoppers and preventing blockages in seeding equipment, providing a baseline for hopper wall inclination—typically, walls are angled steeper than the repose angle to ensure gravity-driven flow, which works well for free-flowing, uniform particles like dry, spherical seeds. However, its reliability is limited by context and material-specific factors: it is highly sensitive to particle size distribution, shape, moisture content, and other properties, and real-world changes (such as seeds absorbing moisture or containing debris) can make it inaccurate in reflecting flow resistance. Additionally, the dynamic conditions of seeding equipment (vibration, impact, varying feed rates) alter actual flow behavior, which static repose angles cannot fully capture. Thus, it must be combined with dynamic flow tests, measurements of internal friction/cohesion, and considerations of operational variables to reliably guide design.

 

 

 

 

Q8: How does the cross-validation of simulated and experimental EDEM results enhance the predictive design of agricultural equipment?
Response: In the research on seed material properties and the design of seed metering boxes, the cross-validation of EDEM simulation results and experimental data is particularly crucial. By comparing the simulated and measured seed flow characteristics (such as seeding rate, retention areas of seeds in the box, and uniformity of seed filling), key material property parameters of seeds (including friction coefficients, shape parameters, and bulk density) can be accurately calibrated. This ensures that the model can truly reflect the behaviors of different seeds (such as grains and beans) in the seed metering box, such as sliding, filling, and collision.  

A validated model can reliably predict the impact of the seed metering box structure (such as the inclination angle of the box wall, the shape of the guide plate, and the size of the seeding outlet) on seed flow. For example, simulations can pre-identify problems such as seed retention in the corners of the metering box caused by excessive inter-seed friction, or uneven seeding due to insufficient wall smoothness. This allows for the optimization of structural parameters during the design phase, avoiding the high costs associated with repeated testing on physical prototypes.  

Such cross-validation enables designers to improve the seed metering box according to the specific material properties of seeds, enhancing seeding accuracy and stability, reducing failures like seed jamming and missing, and ultimately achieving a more efficient seed metering equipment design that is better adapted to seed characteristics.

 

Q9: What experimental conditions need to be rigorously standardized to ensure valid comparisons with numerical simulations?
Response: To ensure valid comparisons between experimental data (such as seed sliding friction angles and repose angles) and EDEM simulations of flow behavior, several experimental conditions must be rigorously standardized: Unify the seed type, moisture content, cleanliness, size and shape distribution, and integrity to avoid fluctuations in material properties. For sliding friction angle measurements, fix the contact surface material, roughness, and hardness (matching those in the simulation model), and control seed placement, loading force, and tilt rate. When measuring repose angles, standardize the method (e.g., funnel or tilting box), funnel dimensions, discharge rate, seed volume, and eliminate external vibrations or air currents. Maintain stable temperature and humidity to match simulation assumptions, calibrate measuring instruments, and standardize data collection procedures (such as image capture angles for repose angles). These standardized measures provide a reliable benchmark for validating EDEM parameters, ensuring simulations align with actual seed flow behavior.

 

 

 

 

 

Q10: What are the current limitations of pelleted seeds in terms of germination?
Response: What limitations do pelleted seeds have in terms of germination, despite their ability to improve sowing efficiency? Pelleting materials (such as clays and polymers) may hinder water and gas exchange, leading to delayed water absorption by seeds and insufficient oxygen supply, which can be exacerbated in waterlogged environments. Overly hard or dense pellets can physically block the radicle and plumule from emerging, while overly fragile pellets may break prematurely during handling, which is instead detrimental to seed protection. Adhesives, pesticides, or fertilizers in the pellets may release toxic components under high humidity, and processing involving high pressure, temperature, or drying can stress seeds, reducing their vitality. Additionally, pelleted seeds have a narrower adaptability to environmental conditions like temperature and humidity, making them prone to poor germination in arid or highly humid environments. Variations in the time it takes for seeds within a batch to break through the pellets can result in poor germination synchrony, affecting the uniformity of crop growth. These limitations vary depending on pellet composition, seed type, and processing methods, increasing the difficulty of standardized application in diverse agricultural scenarios.

 

 

Q11: Enrich your work with bibliographical references.
Response: Thank you for emphasizing the importance of scholarly context. We have added    key references to strengthen the theoretical foundation and methodological rigor, focusing on:
These additions substantiate our innovations in   . All new citations are highlighted in blue in the revised manuscript.

 

 

 

 

 

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

With regard to the responses in the file sustainability-3770087-coverletter.pdf - following corrections are still required in the paper: 

Q5 / Fig. 2: Explanation of "average" is not just for the reviewer, it should also appear in the paper. No table of numerical results added?
Maybe you forgot to add a new Tab. 3.1?
Line 167: New Tab. 32 - do you mean Tab 3.2?

Q7 / Line 210: Mention the type of plastic here for the readers, not just for the reviewer.

Q12 / Fig. 7: You mean the new explanatory Table 8?

Q18 / Fig. 12: Add a reference to Table 1 where the letters are explained.

 

 

 

Author Response

Response to Reviewer 3 Comments

Q1:  Q5 / Fig. 2: Explanation of "average" is not just for the reviewer, it should also appear in the paper. No table of numerical results added?
Response: Thank you for this important feedback. We have addressed both points:

1. A clear explanation of "average" has been added directly to the new Fig. 3 caption.
2. Key numerical results have been incorporated directly into new Fig. 3.

Both modifications are highlighted in yellow in the revised manuscript.

 

Q2: Maybe you forgot to add a new Tab. 3.1?

Response: Thank you for noting this. There was a table numbering error. We have corrected the table sequence accordingly. The updated numbering is highlighted in yellow in the revised manuscript.

Q3: Line 167: New Tab. 32 - do you mean Tab 3.2?

Response: Thank you for catching this typo. This should reference Table 3 (not 3.2). We have corrected this reference in the text. The change is highlighted in yellow in the revised manuscript.

 

Q4: Q7 / Line 210: Mention the type of plastic here for the readers, not just for the reviewer.

Response: Thank you. We have added the specific type of plastic directly in the manuscript text at this location. The revision is highlighted in yellow.

 

Q5: Q12 / Fig. 7: You mean the new explanatory Table 8?

Response: Yes, this refers to the new Table 8.

 

Q6: Q18 / Fig. 12: Add a reference to Table 1 where the letters are explained.

Response: Thank you. The explanation of the letters has been added directly to the new Fig. 13 caption. This revision is highlighted in yellow.

Reviewer 4 Report

Comments and Suggestions for Authors

Insert these comments into the article.

Author Response

Response to Reviewer 4 Comments

Questions:

Q1: Insert these comments into the article.

Response: Thank you for your valuable suggestions. We have incorporated some of these explanations into the manuscript text. The added content is highlighted in yellow.