Comparisons between Aquaponic and Conventional Hydroponic Crop Yields: A Meta-Analysis
Round 1
Reviewer 1 Report
Carefully designed meta-analysis. Technical details clearly explained.
Well-written and easy to read. Some errors in English require attention.
From my point of view, the last part of the introduction, explaining how authors made the estimation of an effect size which enables comparison across studies, choosing the ‘log response ratio’…should be removed from this part as it belongs to the methodology.
Line 29 and 47 and many other. It is written conventional HP when it was said to be specified by cHP. It is a bit confusing.
Line 86. Is it WAS or were captured?
Line 96. Data extraction and processing
Author Response
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Reviewer 2 Report
An interesting and innovative work, I congratulate the authors.
I believe that to improve this work, the following issues should be considered:
In the Introduction, the characteristics of the cultivation systems are defined, it would be appropriate to introduce in this section the concept or the characteristics that differentiate a “coupled system” from an “uncoupled system” or “decoupled”. On line 54, only the type of coupling is indicated, I think this is not enough to properly understand the comparative analysis performed, the figures, the discussion and the conclusions. On line 60, it is indicated:…. c cHP systems. What does the first c mean? It will be convenient to use a letter different from the “n”, to indicate the number of works, or observations (lines 139-140), letter widely used in statistics, of the letter “n” (number of effects) indicated in line 231, and in the figures, etc. On line 139, .. in 2011 (n = 10) On line 151, indicate the meaning of “to ca” On line 162, it is pointed to Figure 3B. What figure is this? On lines 341 and 351, Figure 6A is indicated. Where is this figure?
Author Response
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Reviewer 3 Report
From my view this is an interesting research that could help famers and technicians meeting the demands of the growing population foreseen by FAO in a more sustainable way.
Although, hydroponic systems dated for much longer than aquaponics ones, indeed, this paper presents a quite sound review on the behaviours of certain crops for both production systems: aquaponics and hydroponic, likewise their differences.
Having read the review article, and despite its relevance, I would still suggest authors to improve it making taking into account some comments.
Some time it is quite confusing when talking about cHP conventional Hydroponic Systems or just Hydroponic Systems. Please, if authors think there is a difference in between them, please make it relevance and do explain it.
Regarding the keywords, all the key words are related to statistical terms, but ‘nutrient supplementation, I wonder whether it would be better to set down with some key words more linked to the subject, such as aquaponics and hydroponic productions.
It would be of much interest to show in a table all the data extraction that were taken into account for this review. Authors name, year of publication, fish/aquatic species used in the study, etc…even where the research took place (region or country).
Line 139. (n=10), One bracket missing
Line 151. Is something missing in this sentence…’to ca. 53 kg m-3?
Line 185. Figure 2A. Density should have its units. Be careful because OVERALL EFFECT SIZE is above the 0.0 and 0.2 (x-axis)
It says there is a middle thick line, but in fact it is not very thick.
Figure 2A could be smaller.
Line 218. Figure 5B. Names with capital letter
Line 229. Figure 6. Names with capital letter
Line 233. Aquaculture component. I think should be B (not A)
Line 234. 1. Capital letter for aquatic
Line 248. Figure 7A. Names with capital letter.
Line 249. Figure 7B. Names with capital letter.
Line 252. It is point 2 (not 1) Type of aquaponics system
Line 296. Introducing the sentence with capital letter…Therefore, …
Line 306. There are two brackets with nothing else. (). Please remove them or introduce whatever you wish.
Line 341. It is not Figure 6A but Figure 6.
Line 351. It is not Figure 6A but Figure 6.
Line 372. Conclusion should be in bold like the other sections of the review article.
Objectives are clear stated in the introduction part and the conclusion is coherent with them. Maybe, I would still suggest authors to be more explicit on the conclusions regarding the two last objectives, which are very clear on the results but maybe they are not so clear on the conclusion part.
Line 493. Reference 34 should be in lowercase letters.
Author Response
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