Aerial Spray Droplet Deposition Determination Based on Fluorescence Correction: Exploring the Combination of a Chemical Colorant and Water-Sensitive Paper
and Chunling Chen 1,3,*Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThis paper investigates a UAV-based spray droplet deposition detection method based on fluorescence correction, combining a chemical colorant (Rhodamine B) with water-sensitive paper (WSP), aiming to improve detection accuracy and reduce environmental pollution. Through systematic experiments, the study analyzes the effects of different samplers (ginkgo leaves, crabapple leaves, PVC cards, and WSP), angles, and concentrations on the deposition correction coefficient and verifies the feasibility of the method. The paper has a complete structure, relatively rigorous experimental design, and detailed data presentation, providing practical reference value for the optimization of precision agriculture spraying technology. The innovation lies in proposing a correction method that integrates existing technologies and offering parameter ranges for practical application through multifactor analysis. However, some experimental details are insufficiently explained, the depth of discussion is limited, and the language expression needs further improvement.
Specific Suggestions for Revision
1. The scientific rationale for choosing Rhodamine B (RB) as the fluorescent reagent needs clarification (e.g., why were other fluorescent dyes not considered?), and the theoretical or experimental basis for setting its concentration gradient (0.1--10.0 g/L) should be provided to enhance the rationality of the experimental design.
2. The results section mentions significant differences in deposition among different samplers (e.g., differences between WSP and leaf samplers), but does not thoroughly discuss the underlying mechanisms (such as the effect of leaf surface microstructure on droplet adhesion). It is recommended to incorporate literature and expand the discussion to strengthen the scientific explanation of the results.
3. An analysis of methodological limitations should be added. For example: the experiment only targeted the DJI T30 UAV and specific nozzles--are the conclusions applicable to other models or spraying parameters? Were environmental factors (such as wind speed and light) sufficiently controlled in fluorescence detection? The external validity of the study should be clearly defined.
4. Some sentences contain grammatical errors or redundant expressions (e.g., in the abstract, "Pretests should be conducted based on the test conditions" should be revised to "Pretests should be tailored to experimental conditions"). Additionally, reference formatting should be standardized (e.g., some DOI links are not fully labeled); it is recommended to adjust according to the journal's requirements.
Author Response
Manuscript Number: agriculture-3570685
Title: Aerial spray droplet deposition determination based on fluorescence correction: exploring the combination of a chemical colorant machine and water-sensitive paper.
Dear Editor and Reviewers,
Thank you for your letter and for the valuable comments provided by the reviewers regarding our manuscript. We sincerely appreciate the time and effort you and the reviewers have devoted to evaluating our work. The feedback has been both insightful and constructive, offering meaningful guidance for improving the quality of our manuscript and contributing to the development of our ongoing research. We have carefully addressed all comments and revised the manuscript accordingly. All changes in the revised manuscript are clearly marked in red. A detailed point-by-point response is provided below for your review.
Response to Reviewer 1 Comments
Reviewer #1: This paper investigates a UAV-based spray droplet deposition detection method based on fluorescence correction, combining a chemical colorant (Rhodamine B) with water-sensitive paper (WSP), aiming to improve detection accuracy and reduce environmental pollution. Through systematic experiments, the study analyzes the effects of different samplers (ginkgo leaves, crabapple leaves, PVC cards, and WSP), angles, and concentrations on the deposition correction coefficient and verifies the feasibility of the method. The paper has a complete structure, relatively rigorous experimental design, and detailed data presentation, providing practical reference value for the optimization of precision agriculture spraying technology. The innovation lies in proposing a correction method that integrates existing technologies and offering parameter ranges for practical application through multifactor analysis. However, some experimental details are insufficiently explained, the depth of discussion is limited, and the language expression needs further improvement.
We sincerely appreciate your careful review. Your constructive suggestions have been instrumental in guiding the improvement of our study.
Q1. The scientific rationale for choosing Rhodamine B (RB) as the fluorescent reagent needs clarification (e.g., why were other fluorescent dyes not considered?), and the theoretical or experimental basis for setting its concentration gradient (0.1--10.0 g/L) should be provided to enhance the rationality of the experimental design.
Response1: Thank you for your valuable suggestions.
Regarding the first question you raised about why other fluorescent materials were not considered, we would like to clarify as follows:
As mentioned in Line 94 of the manuscript, previous studies [26] have reported a variety of colorants available for analyzing droplet spraying characteristics. However, Wang et al. (2019) emphasized that Rhodamine B (RB), as a representative water-soluble colorant, offers higher fluorescence detection accuracy compared to other dyes. Due to its high recovery rate and ease of detection, RB is commonly used in aerial spray deposition studies. Rhodamine B (RB) has been widely used in numerous studies on droplet deposition detection, as noted in Line 90 of the manuscript [25]. It is frequently adopted in droplet deposition research due to its proven feasibility, extensive methodological references, and strong theoretical support. Therefore, RB was selected as the fluorescent tracer in this study, as it allows for more accurate quantification of droplet deposition when used with a fluorescence spectrophotometer. In future work, we will also consider incorporating other types of fluorescent dyes to further improve detection accuracy.
Regarding the second issue you pointed out, the experimental design adopted a concentration gradient, which is highly relevant to aerial spray droplet deposition studies and particularly important in the context of this research. Extremely high or low concentrations of the spray solution can adversely affect the accuracy and reliability of the deposition results. Although numerous studies have used dyes as tracers to evaluate pesticide spray deposition on target crops, there is currently no standardized concentration for dye application. A variety of concentrations have been reported in the literature, including 0.1 g/L (Wang et al., 2019), 1.0 g/L (Fang et al., 2019), and 5.0 g/L (Gao et al., 2019). Therefore, in this study, five concentration gradients ranging from 0.1 to 10.0 g/L were selected as the spray treatment levels, covering the range of colorant concentrations reported in the aforementioned studies. The corresponding references are listed below.
- Wang G, Lan Y, Qi H, et al. Field evaluation of an unmanned aerial vehicle (UAV) sprayer: effect of spray volume on deposition and the control of pests and disease in wheat[J]. Pest management science, 2019, 75(6): 1546-1555.
- Fang H, Zhang Z, Xiao S, et al. Influence of leaf surface wettability on droplet deposition effect of rape leaves and their correlation[J]. Journal of Agriculture and Food Research, 2019, 1: 100011.
- Gao S, Wang G, Zhou Y, et al. Water‐soluble food dye of Allura Red as a tracer to determine the spray deposition of pesticide on target crops[J]. Pest management science, 2019, 75(10): 2592-2597.
Q2. The results section mentions significant differences in deposition among different samplers (e.g., differences between WSP and leaf samplers), but does not thoroughly discuss the underlying mechanisms (such as the effect of leaf surface microstructure on droplet adhesion). It is recommended to incorporate literature and expand the discussion to strengthen the scientific explanation of the results.
Response2: Thank you for your valuable suggestions.
Regarding your suggestion to include a more thorough discussion of the underlying mechanisms, we fully agree that this addition is essential to enhancing the integrity and scientific rigor of our study. In response, we have revised the manuscript (see Line 673) by incorporating relevant literature discussing the effects of leaf surface structures and other related factors on droplet adhesion. The revised paragraph and the newly added references are provided below for your review.
The revised paragraph：
“Wang et al.[48] showed that the leaf roughness, surface free energy, its components, and work-of-adhesion for water played important roles in hydrological characteristics, especially work-of-adhesion for water. Cavallaro et al.[49] showed that found that leaf properties such as water contact angle, water droplet attachment, and water retention were determined by surface chemistry (e.g., wax content) and structure (e.g., trichomes, stomatal density, leaf angle).”
The newly added references：
[48] Wang H, Shi H, Li Y, et al. The effects of leaf roughness, surface free energy and work of adhesion on leaf water drop adhesion[J]. PloS one, 2014, 9(9): e107062.
[49] Cavallaro A, Carbonell-Silletta L, Burek A, et al. Leaf surface traits contributing to wettability, water interception and uptake of above-ground water sources in shrubs of Patagonian arid ecosystems[J]. Annals of Botany, 2022, 130(3): 409-418.
Q3. An analysis of methodological limitations should be added. For example: the experiment only targeted the DJI T30 UAV and specific nozzles--are the conclusions applicable to other models or spraying parameters? Were environmental factors (such as wind speed and light) sufficiently controlled in fluorescence detection? The external validity of the study should be clearly defined.
Response3: Thank you for your valuable suggestions.
Regarding the first question you raised about the applicability of the test method to other models or spraying parameters, this issue is of great importance to our study.The aim of this study is to propose a method for correcting deposition assay results on water-sensitive paper through fluorescence-based quantification of the eluted chemical stain and to demonstrate its feasibility. We hope that this method can be adopted by other researchers in a variety of spraying experiments, including those involving different UASS models, spraying parameters, and research subjects. The calibration parameters obtained from experiments may serve as useful references for future related studies. Moreover, this method can enhance the accuracy of subsequent experimental measurements and reduce environmental pollution during the testing process, making it highly valuable for research on spray deposition.
Regarding the second issue you pointed out—the control of environmental factors—we sincerely thank you for highlighting this omission, which is very helpful for improving both the quality and rigor of our research. In response, we have added a detailed description of the relevant environmental conditions in the revised manuscript (see Line 218), and clearly defined the external influences. The fluorescence assay in this study was conducted indoors in a designated laboratory, which was shielded from external light and free from airflow, ensuring that environmental factors remained stable throughout the assay. Thank you again for your valuable suggestions. The revised paragraph is provided below for your review.
“Fluorescence measurements were performed in an indoor laboratory, which was free of wind and shaded from outside light.”
Q4. Some sentences contain grammatical errors or redundant expressions (e.g., in the abstract, "Pretests should be conducted based on the test conditions" should be revised to "Pretests should be tailored to experimental conditions"). Additionally, reference formatting should be standardized (e.g., some DOI links are not fully labeled); it is recommended to adjust according to the journal's requirements.
Response4: Thank you for your valuable suggestions.
Regarding the first issue you pointed out, some of the sentences contain grammatical errors or redundant expressions. We are very sorry that this problem occurred due to our writing deficiencies, but your suggestions have greatly improved the quality of our articles and the reading experience, thank you very much for your suggestions. We have carefully examined and changed the entire article based on the grammatical errors and redundant expressions you have suggested. Some of the statements that have been changed include:
- (Line 33 of the article) Summary section. “Additionally, pretests should be tailored to experimental conditions, and the choice of colorant concentration should be carefully considered.”
- (Line 62 of the article) Introduction section. “Studying the effect of spraying droplets is inherently complex, and current detection methods are typically categorized into into invasive and non-invasive techniques. ”
- (Line 122 of the article) Introduction section. “However, a further review of the literature revealed that some studies do not explicitly or accurately determine of the key parameter of elution recovery. ”
- (Line 603 of the article) Discussion section. “To obtain more accurate elution recovery values for the samplers, the spray concen-tration of RB was also included in the evaluation of this study. ”
- (Line 606 of the article) Discussion section. “However, the results showed that as the concentration of the RB spraying solution in-creased, the elution recovery of the sampler decreased, with the rate of decline gradually slowing.”
Regarding the second issue you pointed out, reference format standardization. We have carefully reviewed and revised the formatting of the references to ensure consistency and accuracy. In addition, Reference [18] has been replaced due to its older publication date and the absence of a DOI link. We sincerely appreciate your guidance and support, which have been helpful in improving the quality of our study.
Replaced references:
[18] Holownicki. R.; Doruchowski, G.; Swiechowski, W.; Jaeken, P. Methods of evaluation of spray deposit and coverage on artificial targets 2002, 5, 1505-0297.
Newly added references:
[18] Simões, I.; Sousa, A.J.; Baltazar, A.; Santos, F. Spray Quality Assessment on Water-Sensitive Paper Comparing AI and Classical Computer Vision Methods. Agriculture 2025, 15, 261, doi:10.3390/agriculture15030261.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsApril 1, 2025
Dear authors,
After reviewing the article titled “Aerial spray droplet deposition determination based on fluorescence correction: exploring the combination of a chemical colorant machine and water-sensitive paper” which was submitted for possible publication in the agriculture journal. I consider that the work addresses an interesting and ad hoc topic with the theme addressed in the special issue as well as with the scope of the journal. However, I think that some aspects could help it improve.
Abstract
The name of the species from which the leaves were used must be in italics.
Do not use abbreviations without having at least once indicated the meaning (for example, PVC, UASS). Applies to the entire document.
Check that the words are not cut with a hyphen. For example, flu-orescent, includ-ing, and samp-plers.
Introduction
The introduction is well written and includes relevant information about the topic, the research problem, the background and concludes by mentioning the objectives of the research. I consider it to be adequate.
Materials and Methods
Line 163 indicates in parentheses the five dye concentrations evaluated.
Consider that table 1 is unnecessary, just add the flow and spray nozzle model in the wording. Therefore, this table must be deleted.
The authors are obliged to disclose the experimental design employed in each of the experiments conducted, thus enabling the replication of the work. Additionally, the statistical analysis employed to identify the differences between the treatments applied must be clearly specified; it is insufficient to merely mention the level of significance.
Results
The results are presented in clear and precise tabular and graphical form, with the most salient findings highlighted in each of the aspects addressed.
Lines 402-403, declaring small differences is very subjective. Statistically speaking, were there significant differences or not?
Lines 423-430 indicate the p values both where significant differences were observed and where they were not observed.
In Table 8, please indicate in the table footer the significance of the asterisk that has been used to highlight certain data points.
Discussion
The authors undertake a thorough analysis of the data by referring to the results and providing sufficient citations to support or explain the findings, as well as to compare the observed results.
The scientific name of the plant species under discussion should be placed in italics.
Conclusions
The conclusions of the study are consistent with its objectives and are derived from the results. They are presented in a straightforward and accessible manner.
References
It is imperative to verify that all references are formatted consistently and adhere to the guidelines outlined in the journal's guide author. It should be noted that the name of the journal may be displayed in full or in abbreviated form.
The reviewer considers that the manuscript may be suitable for publication following minor revisions.
King regards
Author Response
Manuscript Number: agriculture-3570685
Title: Aerial spray droplet deposition determination based on fluorescence correction: exploring the combination of a chemical colorant machine and water-sensitive paper.
Dear Editor and Reviewer,
Thank you for your letter and for the valuable comments provided by the reviewers regarding our manuscript. We sincerely appreciate the time and effort you and the reviewers have devoted to evaluating our work. The feedback has been both insightful and constructive, offering meaningful guidance for improving the quality of our manuscript and contributing to the development of our ongoing research. We have carefully addressed all comments and revised the manuscript accordingly. All changes in the revised manuscript are clearly marked in green. A detailed point-by-point response is provided below for your review.
Response to Reviewer 2 Comments
Reviewer #2: After reviewing the article titled “Aerial spray droplet deposition determination based on fluorescence correction: exploring the combination of a chemical colorant machine and water-sensitive paper” which was submitted for possible publication in the agriculture journal. I consider that the work addresses an interesting and ad hoc topic with the theme addressed in the special issue as well as with the scope of the journal. However, I think that some aspects could help it improve.
Abstract
Q1. The name of the species from which the leaves were used must be in italics.
Response1: Thank you for your valuable comments, which have greatly contributed to improving the scientific quality of our study. We have carefully reviewed and corrected the species names of the leaves throughout the manuscript, ensuring they are properly italicized (see Lines 24 and 163).
Q2. Do not use abbreviations without having at least once indicated the meaning (for example, PVC, UASS). Applies to the entire document.
Response2: Thank you for your valuable comments. We apologize for the omission of specific definitions for some abbreviations in the manuscript due to our oversight. We have carefully reviewed the text and ensured that all abbreviations are clearly defined upon their first appearance (see Lines 23–25 and 70). We sincerely appreciate your suggestion, which has significantly improved the overall quality of our manuscript.
Q3. Check that the words are not cut with a hyphen. For example, flu-orescent, includ-ing, and samp-plers.
Response3: Thank you for your valuable comments. We apologize for the hyphenation errors that caused some words to be improperly split in the manuscript due to our oversight. We have carefully reviewed the manuscript and corrected these issues (see Lines 18, 28, and 30).
Introduction
The introduction is well written and includes relevant information about the topic, the research problem, the background and concludes by mentioning the objectives of the research. I consider it to be adequate.
Response: We sincerely appreciate your careful review. Your constructive suggestions have been instrumental in guiding the improvement of our study.
Materials and Methods
Q4. Line 163 indicates in parentheses the five dye concentrations evaluated.
Response4: Thank you for your valuable comments. We have added the spray concentrations of the five dyes in parentheses to clarify the information (see Line 165 of the manuscript).
Q5. Consider that table 1 is unnecessary, just add the flow and spray nozzle model in the wording. Therefore, this table must be deleted.
Response5: We sincerely appreciate your insightful comments, which have significantly enhanced the conciseness and scientific rigor of our manuscript. In response to your suggestions, we have removed Table 1 due to its limited content and have incorporated the relevant information into the main text (Line 170). All subsequent table throughout the manuscript have been updated accordingly to reflect this change.
Q6. The authors are obliged to disclose the experimental design employed in each of the experiments conducted, thus enabling the replication of the work. Additionally, the statistical analysis employed to identify the differences between the treatments applied must be clearly specified; it is insufficient to merely mention the level of significance.
Response6: Thank you for your valuable comments. We have reviewed the manuscript and added statistical descriptions for the relevant treatments and formulas, including the coefficient of variation and standard deviation, to enhance the clarity and rigor of the statistical analysis (see Line 342).Furthermore, we adopted different analytical methods tailored to specific parts of the study. To evaluate the performance of the atomization nozzles, we analyzed the diffusion values and relative span of each nozzle, and quantified their variability by calculating the coefficient of variation, standard deviation, and conducting significance testing.For the analysis of elution recovery rates, a one-way analysis of variance (ANOVA) was conducted, followed by multiple comparisons using the least significant difference (LSD) method to identify significant differences among treatments.In the correction of water-sensitive paper deposition, several methods were employed to calculate correction coefficients, including the ratio method, integral method, and linear fitting method. We sincerely appreciate your careful review. Your constructive suggestions have been instrumental in guiding the improvement of our study.
Results
The results are presented in clear and precise tabular and graphical form, with the most salient findings highlighted in each of the aspects addressed.
We sincerely appreciate your careful review. Your constructive suggestions have been instrumental in guiding the improvement of our study.
Q7. Lines 402-403, declaring small differences is very subjective. Statistically speaking, were there significant differences or not?
Response7: Thank you for your valuable comments. To reduce subjectivity, we calculated the coefficient of variation (CV) and standard deviation of the RS values for the 12 SX110015VS aerial nozzles, which were 3.4% and 0.0384, respectively. These metrics were used to assess the overall significance and variability of the data (see Lines 403–406 of the manuscript). The manuscript has been revised accordingly as follows:
“Additionally, the RS values for the 12 nozzles ranged from 1.07 to 1.23, showing no statis-tically significant differences among them. The coefficient of variation (CV) was 3.40%, with a standard deviation of 0.0384, indicating minimal variability within the dataset.”
Thank you again for your kind help and guidance on our research.
Q8. Lines 423-430 indicate the p values both where significant differences were observed and where they were not observed.
Response8: Thank you for your valuable comments. In the significance analysis, we examined the elution recovery of the same sampling material under different spraying concentrations. A one-way analysis of variance (ANOVA) was conducted, followed by multiple comparisons using the least significant difference (LSD) method to determine significant differences between treatments.The results revealed significant differences not only among different spraying concentrations for the same type of material, but also among different types of samplers under varying colorant concentrations. Due to the large volume of data, the results were presented in graphical form for clarity.In response to your suggestion, we provide p-values reported in the significance analysis to provide a more detailed interpretation (see Lines 426–432 of the manuscript).Thank you once again for your helpful suggestions, which have contributed to the improvement of our study. The manuscript has been revised accordingly as follows:
“As shown in Fig. 7(b), the significance analysis indicated that elution recovery dif-fered significantly among samplers at the p < 0.05 level across the five RB spray solution concentrations. Specifically, significant differences were observed between the PVC sam-pler and both types of leaves, while no significant difference was found between the two leaf types. Furthermore, the elution recovery of the PVC sampler varied significantly with RB concentration, whereas the two leaf samplers exhibited no significant variation, con-sistent with the overall elution recovery trends.”
Q9. In Table 8, please indicate in the table footer the significance of the asterisk that has been used to highlight certain data points.
Response9: Thank you for your valuable comments, which are of great help in improving the quality of our article. Due to our omission resulting in the lack of asterisk annotations, we have added the significance of the asterisks after Table 8, which represent coefficients of variation greater than 15% for this data.
Discussion
The authors undertake a thorough analysis of the data by referring to the results and providing sufficient citations to support or explain the findings, as well as to compare the observed results.
We sincerely appreciate your careful review. Your constructive suggestions have been instrumental in guiding the improvement of our study.
Q10. The scientific name of the plant species under discussion should be placed in italics.
Response10: Thank you for your valuable comments, which have played an important role in enhancing the scientific accuracy of our research. We have carefully reviewed and corrected the plant species names throughout the manuscript, ensuring that they are properly italicized (see Lines 664, 666–668, 671, and 727 of the manuscript).
Conclusions
The conclusions of the study are consistent with its objectives and are derived from the results. They are presented in a straightforward and accessible manner.
We sincerely appreciate your careful review. Your constructive suggestions have been instrumental in guiding the improvement of our study.
References
Q11. It is imperative to verify that all references are formatted consistently and adhere to the guidelines outlined in the journal's guide author. It should be noted that the name of the journal may be displayed in full or in abbreviated form.
Response11: Thank you for your valuable comments. We have carefully reviewed and revised the formatting of the references to ensure consistency and accuracy. In addition, Reference [18] has been replaced due to its older publication date and the absence of a DOI link. We sincerely appreciate your guidance and support, which have been helpful in improving the quality of our study.
Replaced references:
[18] Holownicki. R.; Doruchowski, G.; Swiechowski, W.; Jaeken, P. Methods of evaluation of spray deposit and coverage on artificial targets 2002, 5, 1505-0297.
Newly added references:
[18] Simões, I.; Sousa, A.J.; Baltazar, A.; Santos, F. Spray Quality Assessment on Water-Sensitive Paper Comparing AI and Classical Computer Vision Methods. Agriculture 2025, 15, 261, doi:10.3390/agriculture15030261.
The reviewer considers that the manuscript may be suitable for publication following minor revisions.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsDear Authors,
I enjoyed reading this publication.
General comments:
The topic of pesticide drift is super important, both for the environment and for treatment efficiency. This study focused on providing more information regarding both of these questions. It provides an abundance of new or re-evaluated information that can be used by practitioners or researchers in future studies.
Please my specific comments for some issues in the methodology that need addressing:
- Line 170: “table 1” – the table is not referenced in the text anywhere. Please revise.
- Line 170: “Repetition” – it is not clear what repetition means. In the text above it states 5 different concentrations. Not repetition of the exact same experiment. Please clarify.
- Line 178-180: “FALL … VUASS… “ - the parameters in the equation is F_ALL (FALL). either use underscore here as well, or use the full name in the equation as well but the parameters notation MUST MATCH completely. This is something that was done accurately for equations 3 onward. An oversight perhaps here. Please revise.
Furthermore, the units in equation 1 do not match. You are missing factor corrections at the very least. [m/s]*[m]*60[s/min]*[L/min] = m^2*L/(min^2). Which is not [L/min]. please revise and correct. - Line 313: ‘equation 6’ – what is R? is it the same R in equation 10? If so, why are you dividing by it again? Please clarify and revise.
Author Response
Manuscript Number: agriculture-3570685
Title: Aerial spray droplet deposition determination based on fluorescence correction: exploring the combination of a chemical colorant machine and water-sensitive paper.
Dear Editor and Reviewers,
Thank you for your letter and for the valuable comments provided by the reviewers regarding our manuscript. We sincerely appreciate the time and effort you and the reviewers have devoted to evaluating our work. The feedback has been both insightful and constructive, offering meaningful guidance for improving the quality of our manuscript and contributing to the development of our ongoing research. We have carefully addressed all comments and revised the manuscript accordingly. All changes in the revised manuscript are clearly marked in blue. A detailed point-by-point response is provided below for your review.
Response to Reviewer 3 Comments
Reviewer #3: The topic of pesticide drift is super important, both for the environment and for treatment efficiency. This study focused on providing more information regarding both of these questions. It provides an abundance of new or re-evaluated information that can be used by practitioners or researchers in future studies.
We sincerely appreciate your careful review. Your constructive suggestions have been instrumental in guiding the improvement of our study.
Q1. Line 170: “table 1” – the table is not referenced in the text anywhere. Please revise.
Response1: Thank you for your valuable suggestions. Your advice has greatly contributed to enhancing the conciseness and scientific rigor of our paper. Given the limited content of Table 1, we have decided to remove it and integrate the relevant information into the main text at line 168. The manuscript has been revised accordingly as follows:
“The experiment consisted of 12 treatment groups (N1 to N12), each repeated five times under identical conditions to minimize the influence of experimental error on the results. The spraying flow rate was set at 0.465 L/min.”
Q2. “Repetition” – it is not clear what repetition means. In the text above it states 5 different concentrations. Not repetition of the exact same experiment. Please clarify.
Response2: Thank you for your valuable comments. We sincerely apologize for any confusion caused by the insufficient clarity in our previous description. In this context, “repetition” refers to the repeated measurement and collection of multiple datasets under identical experimental settings and conditions. This approach is employed to reduce the impact of experimental errors on the final results. We have added a clarification of the term “repetition” in the revised manuscript (line 168). The manuscript has been revised accordingly as follows:
“The experiment consisted of 12 treatment groups (N1 to N12), each repeated five times under identical conditions to minimize the influence of experimental error on the results. The spraying flow rate was set at 0.465 L/min.”
Q3. Line 178-180: “FALL … VUASS… “ - the parameters in the equation is F_ALL (FALL). either use underscore here as well, or use the full name in the equation as well but the parameters notation MUST MATCH completely. This is something that was done accurately for equations 3 onward. An oversight perhaps here. Please revise.
Furthermore, the units in equation 1 do not match. You are missing factor corrections at the very least. [m/s]*[m]*60[s/min]*[L/min] = m^2*L/(min^2). Which is not [L/min]. please revise and correct.
Response3: Thank you for your valuable comments.
Thank you for pointing out the inconsistency between the parameters and the textual description. We sincerely apologize for the oversight. Due to our carelessness, the parameters in the formula did not align with the corresponding explanations in the text. We have carefully revised the relevant section (lines 178–182) and thoroughly reviewed all formulas in the manuscript to ensure consistency between the equations and their associated parameter definitions.
Thank you for pointing out the issue of unit inconsistency in Formula 1. We have thoroughly reviewed the formula and corresponding units. We apologize for the misunderstanding caused by our unclear description. The formula has now been revised and clarified accordingly. Specifically, in the expression [m/s] × [m] × 60 [s/min] × [L/min], the last term [L/min] corresponds to the DMED term in the formula, which represents the spray volume per hectare. Its correct unit should be (L/hm²), rather than [L/min], where 1 hm² = 10,000 m². We sincerely appreciate your insightful comments, which helped us improve the accuracy of our work.
The correct unit corresponds to (m/s) * (m) * (s) * (L/hm²) *10000 = (L/min).
Q4. Line 312: ‘equation 6’ – what is R? is it the same R in equation 10? If so, why are you dividing by it again? Please clarify and revise.
Response4: Thank you for your valuable suggestions. We sincerely apologize for the confusion caused by the repeated use of the symbol R in both Formula (6) and Formula (10). R represents the elution recovery rate (%). Due to the lack of clarity in the original expression of Formula (6), we have now moved R to Formula (10) to better emphasize that the elution recovery rate was considered when calculating the amount of droplet deposition per unit area. We have revised the formulas accordingly and added a clear description of R in the main text.(lines 312–325) Once again, we greatly appreciate your insightful feedback, which has helped us improve the quality of our work.
Author Response File: Author Response.pdf
