Influence of Mechanical and Intelligent Robotic Weed Control Methods on Energy Efficiency and Environment in Organic Sugar Beet Production
Round 1
Reviewer 1 Report
Thank you for presenting an interesting paper based on an agricultural experience conducted according to accepted principles in agronomy. The work is well written, readable for the audience, the results clearly and logically elaborated. Please respond in detail to the comments below.
I think that one of the serious shortcomings of the work is insufficient confrontation of the obtained results in the research with the state of knowledge in a similar area. I think that the authors should separate a separate part "discussion" in which they describe exactly what was obtained and what is known.
Comments on the title. I am of the opinion that the title of the article is inconsistent. On the one hand you point to energy and greenhouse gas efficiency, on the other you suggest an interest in intelligent weed control systems. Please restructure it so that it forms one common content. It is worth including in the title that you are working with sugar beet.
Abstract
In the abstract it is useful to write where and when the research was conducted.
Introduction
Please briefly mention which weed species are particularly troublesome in sugar beet production with reference to Lithuania.
Can the use of mechanical weed control alone fully protect the crop? Should herbicides still be used?
Have you looked at the impact of intensified mechanical protection on soil properties? Is the yield being reduced by chance, not just because of the presence of weeds, but because the soil is too compacted?
Materials and methods
The assumptions you have made about yields for a robotic or automated system unfortunately do not convince me. I think it is too broad an interpretation. You refer to scientific papers, but these show that experiments were carried out under different conditions. This is a serious methodological error.
I would like you to briefly explain how the robot works. How does it select the right working area? How does it recognise weeds? Which beet/weed development stage can it be used for?
Results
Have you made calculations to indicate after how many years the investment in an automated/robotic system would pay off for the farmer?
Author Response
Dear Reviewer,
Thank you very much for taking the time to review our manuscript and provide valuable comments. The manuscript was corrected based on all the reviewer comments. Each of the comments helped to improve the quality of the individual sections and subsections and the overall manuscript.
Please see the attachment
Author Response File: 
Author Response.docx
Reviewer 2 Report
The manuscript with the title „Analytical assessment of energy use efficiency and greenhouse gas emissions: intelligent robotic weed control systems against conventional methods” is addressing an important part of modern resp. future weed control systems: their energy use efficiency within a cropping system. The manuscript is good to read and easy to follow. Still some points are missing or not yet ready.
First is the title: I don’t know if your use of the word “analytical” in the title and throughout the paper is correct. But I am not an native speaker. Still, I think there are better titles. Think about including cropping system to it, but avoid the term “conventional” at all. In connection with weed control, this is associated with herbicides and your work does not address chemical weed control.
L39 5 weeds/ha reduce the yield is not from Kunze et al. 2015. They cited Kropff and Spitters 1991 with this value. You did the same mistake in Table 2. I.e. the value of 0.071 MJ^-1 is not part of your cited references. It is only a cited in the references. The value originates from: “On the study of energy use and GHG (greenhouse gas) emissions in greenhouse 479 cucumber production in Yazd province” J.A. Dyer, R.L. Desjardins, 2006.
Please correct that and carefully revise your references!
L44 (52% of the EUROPEAN organic farmland)
L57 you claim that chemical weed control is expensive. Please give a reference that compares methods. Best would be one that includes your methods as well.
L64-70 I stumbled over the second sentence, when you mention living mulch after anouncing “crop mulching”. I propose to change the paragraph to: “Mulching is another method of weed control that can be also used in organic 64 crops. Plant mulch residues on the soil surface alter the physical and chemical environment 67 of weed seeds, thereby inhibiting weed germination and growth. As an alternative to me-68 chanical weed control, thermal weed control with heat, electricity, flame, hot water, and 69 foam can be used [4,23]. The work of Kunz [22] revealed that the use of a living mulch in sugar beet produc-65 tion can reduce the amount of herbicide by up to 65% and the number of weeds by up to 66 83%.
L118-121 I propose: Therefore, the aim of this study is to analyse, evaluate, and compare the impact of conventional as well as robotic weed control methods regarding the energy and environmental performance in organic sugar beet production.
Additionally, I propose a sentence where describe that you are doing a calculation of a standardised cropping system.
L122 M&M: You describe the methods and underlying principles, but the actual way how you calculate your result is missing. I miss the part, where you present your formula(s) and how they combine to the cropping system. You mentioned "average” values (L282) so you did more than one calculation for every method? The name of the methods include "3x" what does it mean? Three time applications? Please clarify this in the text.
L125 please avoid the word “conventional”
L126 what do you mean with "with weeds"?
L130-134 Do you mean something like: "the analysis of another three... were based on literature rather than trial results.”
L135-144 Please refer to the EX numbers in this paragraph? I can’t find, which working speed/information is for the methods.
L187 Table2. Think about an additional column to identify input and output variables.
L195 I do not understand „additional“. Do you mean together E6 and E7 get 18% advantage?
L203 Even though it is possible to combine results with discussion think about separating them. In that way, it is easier to discuss the results together and come to a clear and sound finding.
L228 Figure 2 The weed control part is very thin in this graph. Could you try a graph with proportions? All bars would be at 100% and weed control would have always the same colour. The method is described by EX.
L233 The result on the yield more or less reflect your fixed parameters on the yield estimation: 11% and "additional" 7%. You made these corrections with purpose, but I think you should discuss it.
L240-241 What years do you refer to? You did not account for years in your calculations, did you?
L257 This would be a nice sentence in the method part! I missed it there.
L382 we can draw THE important
L385 what is the promising future you conclude?
Author Response
Dear Reviewer,
First of all we would like to thank Reviewer for valuable comments, detailed recommendations and contributions to improving the quality of this manuscript. All of the issues raised in the Reviewer comments were corrected. All revisions are highlighted in the text.
Please see the attachment
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Dear Authors,
congratulations on the good corrections to your article. I think, that it is acceptable in its present form.
Author Response
Dear Editor,
Thank you for the positive evaluation of our manuscript. Following to your remark, we have supplemented the discussion section of the manuscript with the limitations of the study.
