Role of Spectrum-Light on Productivity, and Plant Quality over Vertical Farming Systems: Bibliometric Analysis

Round 1

Reviewer 1 Report

The review manuscript deals with an interesting and actual topic, connected with vertical farming lighting. This type of plant cultivations gain a lot of attention in recent years and has a lot of specificities, compared to greenhouse lighting. However, in this manuscript I find numerous uncertainties, providing important information. It lacks precision, and in some cases, basic knowledge. The result discussion is weak, compared to the objective of study.

 

Title “Managing lights and plant response in a vertical farming” is dedicated for lighting technologies, while large part of manuscript deals with the terms and methods above lighting? Title should be updated according contents. Managing – the contents are not about “managing”. The contents only analyze the light sources used for vertical farming research, but this does not present the real lighting choices for practical applications.

 

Introduction weak, narrow background for the necessity of the VF technology

 

Table 1, Light intensity – PPFD units and PAR meters are used to measure LED light intensity, Lux is not acceptable unit

 

Table 1, PAR “It is defined as the specific waveband which excites chlorophyll molecules, and thus initiates the flow of energy required in photosynthesis [20]” not only chlorophyll is acceptor of the photosynthetic photons, please revise the information here and definition of PAR. Picture of the PAR spectrum, please provide the source of it.

 

Table 1, LUE and RUE (equation no. 3) – please revise and clearly indicate, how RUE is different form LUE, because according current equation, they are the same.

 

Table 1, electromagnetic spectrum – the meaning of light spectrum is not explored enough.

 

Table 2. Photosynthesis is a physiological process, not a measure. Yes, it is common to deal with photosynthetic parameters, like productivity, photosynthesis intensity, stomatal transpiration etc., measured by for e.g. Licor photosynthesis system.

 

Table 2, Leaf area – “It is a parameter that determines the amount of photoassimilates produced and affects their growth, development, and productivity [27]” their=who’s?

 

Table 2, TDM – “It represents the net gain in dry matter and it is considered one of the best parameters for indicating plant quality [33]. Moreover, plants with a high TDM content show high growth potential and field yield.” – please revise the information. How authors relate TDM with the quality of plant? Too high TDM is also the reduction in quality. Field yield- is it acceptable term in VF?

 

L94 – ”Since the middle of the 20th century, no further lighting developments had been made” – Misleading contents, please provide more accurate dating for different types of lighting or rephrase. Currently it look like there was no progress for more than 150 years. Also, please include high pressure sodium and fluorescent lighting, which were the standard for the long years before LEDs.

 

L90-92 “Scientific references to the use of lamps in agriculture 90 dating back more than 150 years have been found. Mangon [34] used incandescent lighting [35], Siemens [36] used coal-generated lighting where its efficiency was also analysed economically, and Murdoch [37] made a technological leap using mercury vapor lamp – Misleading contents. Were these authors the first to introduce the  new types of lamps in scientific literature, or they were the first, who published?

 

Does the study include only sources, having key-word of vertical farming? How about numerous works, made with CEA, controlled environment systems?

 

L104-105 “economic investment in terms of electricity consumption and labour, although improvements are being sought to reduce these costs and even specific crops of higher market value have…” Please provide more correct information about economic investments in terms of electricity consumption – do you mean that LEDs require more of input, compared to other types, or you man that lighting generally is requesting high expenses for electricity?

 

L109-117 too weak substantiation for the value of light in vertical farming.

 

L269 “where the specific spectrum-LED peak 450 nm (white colour) was the most used” – 450nm is a blue light

 

L281 and elsewhere, please provide: parameters improved, compared to what?

 

L284 “with a spectrum of  435 nm on” – single wavelength is not yet a spectrum.

 

Figure 8 – nice idea, that field area represents the percentage of publications, using specific spectra. However, the proportions of the pictures in these areas should be revised equally.

 

L291 – spectrum used not in vertical farming itself, but vertical farming research

 

In table 3, several abbreviations not explained elsewhere, DDT, PFAL, WUE.

 

Result and discussion part is more like only results, as no value, meaning of results is described, While conclusions is more suitable for discussion.

 

 

 

 

 

 

Author Response

Gracias por tus comentarios. Archivo PDF adjunto con las respuestas.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors, thank you for the opportunity to contribute to your work as a reviewer. I think, that this article is a valuable summary for the present knowledge about experimental settings for plant production in PFAL systems, however, efforts have to be made in order to communicate the outcomes of the ms to the readers.

General comments:

I think, that the authors have to decide about the composition of the article, to me, it seems, that now it is very segmented and the main parts (topics) do not have a strong logical line. The MS starts with an intro about PFs, then comes a table about the very basic terms used for light characterization, a detailed analysis of bibliographic data, again a part about PFs, an analysis about growing media and technology, and species, and finally, comes the analysis of light characters used. Among these subtopics there is a fluctuation in scientific level and this makes it a bit imbalanced and confusing.

The title does not reflect, what the ms deals with. I don’t understand, why light is emphasized as the MS deals with the experimental design of PFs as it is. Therefore, I suggest to change the title to something more relevant.

The abstracts is far too general, and speaks about the light related conclusions only. Please revise.

Table 1. I don’t suggest to keep this table as it is. To me it is very strange, that illustrations are stuffed into cells and the texts in the second column is also very general. Please transform this information into text and be more specific. Additionally, these terms are generally used, therefore the definition of these are very repetitive and unnecessary.

Figure 3. I don’t see the aim of this figure. It is very general and confusing, especially the terms in the top line. Their sequence means timeliness, or just a random listing?

Figure 8 is very crowded in its present state. I suggest excluding the wavelength graphs and substitute it only with colors. The right bottom part is obviously the most critical and it is unreadable now.

Table 3 is a very valuable part of the ms. I would like to see more columns here detailing the growing media and farming method as well. I also suggest to create an excel spreadsheet as a supplementary material which is searchable for the audience.

In the conclusion I would like to see more future trends regarding knowledge gaps and directions, besides general statements.

Author Response

Thank you for yours comments. Attached pdf file with answers.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Manuscript has improved after revisions, however, there are still several critical aspects.

The title must be revised, more representing the objective of the study, which is much wider than the current title of the manuscript. Speciffic comments below.

There is lack of precision in representing the main terms of the lighting and vertical farming. In my oppinion, it is of the main importance, to present the terms correctly in the review manuscript. More detailed comments below.

 

Title: „Role of light-quality parameters on productivity, resource use efficiency and bioactive compound profiles in vertical farming systems” is still not correct.: “bioactive compound profiles in vertical farming systems” – these compounds are in plants, cultivated there, but not in systems themselves; “Light quality parameters” – not so much of them discussed in the manuscript, just the “color” of the light, not giving specific information on the correct wavelengths. General Vertical farming trends and parameters, for which the largest part of the manuscript is dedicated, are not reflected in the manuscript, while the productivity and bioactive compounds are just mentioned in the manuscript.

 

L35 “With natural resources” – I would discuss about consistency of this statement within the study.

 

Table 1 :

”It is defined as the specific waveband which excites molecules, and thus initiates the flow of energy required in photosynthesis [24].” – “excites molecules” – please be more specific, photosynthetic pigment molecules, or similarly.

“Based on its SPD, a light source will have a conversion factor that can be used to determine to PPFD” Determine to PPFD – from what? Direct PPFD measurement, using PAR sensors is a standard procedure, it is used in the majority of studies revised in this paper, therefore the conversion of LUX/PPFD is only supplemental option. Can be mentioned, but not in the first place and must be expalained more specificly than in this current statement.

Electromagnetic spectrum – please do not confuse with the limits of electromagenetic spectrum and visible light. Please describe both separately.

How about UV-A ir Far red light? They are mentioned in the text. How would yoi address them to this classification of light spectrum?

The terms in the table could be rearranged starting from Electromagnetic spectrum, then PAR and PPFD.

Same remark as previously, please give appropriate descriptions of RUE and LUE, in current version ir still not clear, how are they similar/different.

 

Table 2:

I will repeat my previous comment: the description/and representation should be equal for all parameters. Its not good to present photosynthesis equation for photosynthetic parameters, but leaf area meter for leaf area, as the parameter. Please revise thoroughly, the pictures representing dry mater and productivity in this table are not specific. Maybe the “representation” section could be removed at all.

Conclusions – they are dedicated for lighting parameters, while the large part of the study is dedicated for bibliographic study of the keywords in vertical farming, cultivated plants etc.

 

 

Pictures in the manuscript, that are not the product of the authors – please revise the correct citation according journal requirements. 

Author Response

Attached file

Author Response File: Author Response.docx

Reviewer 2 Report

Dear Authors, thank you for considering my suggestions.

Author Response

Attached file

Author Response File: Author Response.docx