Leveraging Unmanned Aerial Vehicle Technologies to Facilitate Precision Water Management in Smallholder Farms: A Scoping Review and Bibliometric Analysis

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This study highlights a significant increase in scholarly research on utilising UAVs for precision water management over the past decade, and indicates that UAVs in agriculture are gaining prominence and exhibit substantial potential for various precision agriculture application. It is a meaningful work, however, the manuscript does not highlight how drones can facilitate precise water management on smallholder farms, which is important for readers.

1. In the part of ‘Result’: I propose to increase the quantitative evaluation of the effectiveness of drones in improving water management.

2. In the part of ‘Discussion’: The content is rich but slightly messy, it is recommended to use  subheadings, or you can combine the results and discussion in this manuscript.

3. Figure 7 needs to be supplemented to describe what the different colors represent

Author Response

Kindly refer to the attached document.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

1. From the perspective of smallholder, the feasibility of UAV comparing with RS, including cost of UAV or operation training, etc. is suggested to analyze deeply.

2. Higher resolution and easier operation could be the advantage of UAV technology, while the discontinuous recording and equipment without high technological detectors might not be neglected.

3. It is better if the most feasible operation and analysis technology is chosen for smallholder in this study.

4. Besides getting the highest citations and maximum number of publications with statistics, the greatest contribution in this field is suggested to complemented.

 

Author Response

Kindly refer to the attached document.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

drones-3174227 “Leveraging Unmanned Aerial Vehicle Technologies to Facilitate Precision Water Management in Smallholder Farms: A Scoping Review and Bibliometric Analysis” A.Yacoob, S.Gokool, A.Clulow, M.Mahomed, T.Mabhaudhi

This review is hard to classify as there are so few papers to summarise over 11-years. The best part is Section 4 which looks at the implications for smallholder enterprises and the real-world limitations to applying these methods for poor farmers. This part however is only 2 pages long, with the rest various textual analyses and word pictures. The text is well organised and easy to read overall.

In Table 4 are the listed percentages meant to be integers, e.g., the first two values are 0.14 which is 14%? I suspect what is listed are proportions not percentages.

Author Response

Kindly refer to the attached document.

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

This paper comprehensively evaluates the application reserves of unmanned aerial vehicles (UAVs) in evapotranspiration (ET) estimation in the agricultural field through bibliometric methods. An in-depth analysis of 49 high-precision peer-reviewed papers selected from the Scopus database using Biblioshiny and VOSviewer tools shows that drones show great potential in multiple application fields of precision agriculture (PA). However, the study also has some shortcomings:

 

1. The title of the article mentioned small farmers, but there was no research on small farmers during the literature search, and there was a lack of in-depth analysis and discussion of small farmer agriculture. Is there any discrepancy between the scope of the study and the title?

 

2. Does not include non-English literature. Are too few search engines mentioned in the methods section of the article, resulting in insufficient comprehensive literature for search analysis?

 

3. Various ET estimation models are mentioned in the article, but the comparative analysis of the applicability and limitations of these models in smallholder agriculture is not in-depth enough.

 

4. The article does not explicitly mention how drone technology can effectively help small farmers improve water efficiency and crop yields. The conclusion of the article is vague, do you have any specific suggestions or solutions that impact smallholder agricultural supplementation?

Comments on the Quality of English Language

Generally speaking, the language part is relatively professional and meets the requirements of the paper, but some language descriptions are too complex and difficult to read.

Author Response

Kindly refer to the attached document.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

This paper has revised. I have no more comment. 

Reviewer 4 Report

Comments and Suggestions for Authors

I would like to thank the author for his detailed response to my last review comments and acknowledge the revisions made to the paper.  The revised paper is more explicit in the practical application of UAVs in smallholder farming environment, and the author also conducts a more in-depth comparative analysis of ET models, which solves the problem that the previous paper's comparative analysis of the applicability and limitations of ET estimation models in smallholder agriculture is not in-depth enough.  The authors explained why there were some inconsistencies between the title of the study and the scope of the study, as well as the scope of the literature search, and I understand this and accept their reasons.

Comments on the Quality of English Language

In the English language part, the language of this paper is relatively standardized and meets the requirements of literature review. For some sentences, such as: “An initial literature search was conducted using academic search engines, such asElsevier, Scopus, and Science Direct,  to identify prominent keywords in published papersfrom high-impact-factor journals that addressed three main areas of  interest:  precisionwater management (S1), unmanned aerial vehicles (S2), and crop water status (S3). "It's a bit complicated, but could be improved to make it more concise.