Bioponic Cultivation Using Chicken Droppings to Produce Lettuce Plants (Lactuca sativa rz) Uncontaminated by Trace Metals
, Michel Mpundu Mubemba 2, Clément Burgeon 1 and M. Haïssam Jijakli 1,*Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThis article reports a practice of cultivating lettuce using fermented chicken manure as nutrient solution for soilless cultivation, aimed at vegetable cultivation in areas heavily contaminated by mining activities, which is highly significant. Overall, the author conducted detailed observations and recordings, but unfortunately, the presentation of these activities is not well articulated, with many research details being unclear, and the content of the article as a whole being lengthy, requiring improvement in many aspects, as follows:
1. In line 32 of the abstract, "In fact, bioponics not only generate lettuce plants which do not pose health risks but could also produce greater yields compared to soil crops." This conclusion is not supported by the content of this article as the study did not involve a comparison with soil cultivation.
2. The introduction part is somewhat lengthy, and some content could be omitted, such as vermicomposting, optimal conditions for nitrifying bacteria, and other content not directly related to this study.
3. In line 166, what does "biomedia (25 L)" and "prepared solution" specifically refer to?
4. In line 187, please verify the pore size of the “0.25 µm flour sieve”.
5. In line 192, why is TAN set to 150 mg/L and not another value? Does this mean that the TAN in the diluted nutrient solution (before aerobic digestion) is 150 mg/L?
6. In line 221, does this mean that the TAN in the nutrient solution in the cultivation system is adjusted to 150 mg/L every 7 days? How is this adjustment made?
7. In line 302, what is the "mother bioponic nutrient solutions"?
8. In Figure 3a, what is the unit of TAN? Please verify the data.
9. In line 312, what does "the optimum" refer to?
10. What do T1-T4 refer to? It is recommended to use line graphs or data tables.
11. In Table 2, decimal points should be represented by periods, not commas.
12. The conclusion section should briefly summarize the main findings of this article.
13. In Table B.1, according to the Materials and Methods section, the initial values of TAN in the nutrient solutions (before aerobic digestion) for all treatments should be 150 mg/L, and this value should theoretically remain constant every 7 days. Is that correct?
14. The discussion is not sufficiently in-depth and needs to be analyzed and compared with previous studies.
15. There are some grammatical issues that I have marked on the manuscript.
Comments for author File: 
Comments.pdf
There are some grammatical issues that I have marked on the manuscript.
Author Response
Please find attached the answers provided
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis may be an interesting paper, however with several inconsistencies and some faults.
Here are some of the critics which should be addressed during major revision.
1. Explain TAN in abstract!
2. What are sustainable nutrient solutions, questionable with respect to the limited availability of mineral fertilizers, worldwide, especcially P (Gerke, 2021, Agronomy, 11: 1079).
3. Give arguments why chicken manure is used, abundance, availability? Give approximate cacluations on its availability and possible vegetable production.
4. What is a 0.25 micrometer flour sieve? Explain!
5. Fig. 3. TAN, which unit?
6. Table 2, Where do the trace elements come from? Unit (mg/kg9 related to dry matter content?
7. Fig. 6 Again, TAN, P, K and NO3-N units!
8. L 417 ff. Where comes the pH changes in the nutrient solution come from?Explain in detail! It is not the N-form absorption by microorganisms.
9. L 463 ff. Decrease in phosphorus?? The following explanation highly speculative!
Comments on the Quality of English Language
see above!
Author Response
Please find attached the answers provided
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsAn article with the title "Bioponic cultivation of lettuces (Lactuca sativa rz) in an environment heavily polluted by mining activities in the Katangese Copperbelt in the Democratic Republic of Congo" needs consideration for abbreviation. Environments contaminated with metals or other undesirable substances occur globally, so omitting a specific location from the title could make it more universal and of interest to a wider range of readers. In addition, consideration should be given to revising the main objective of the study, as the overall goal of addressing environmental pollution is not clearly reflected in the title and keywords. The research objective of using chicken manure for hydroponic cultivation should also be included in the title.
The literature review is correct, but the connection between increasing poultry production and greater supplies of chicken manure and its potential use could be more emphasized.
The methodology of the experiment is described in detail and allows for potential implementation on a larger scale. The results of the study are correctly presented, but it should be noted that there are many unidentified factors that may have contributed to the high error variance in the ANOVA analysis for the initial stages of the study.
The findings and conclusions are sound and may inspire other researchers interested in conducting similar modified experiments with more controlled factors. The lack of control of many factors can be the basis for adapting the experiment to other conditions.
The literature cited is too broad and beyond the scope of the issues described. Consideration should be given to reducing less relevant items and focusing on those directly related to the topic of the article.
Minor comments:
In Table 1, the column "Crop types" is not needed because the article is only about lettuce. It is recommended to change the title of the table and add information about the plant species, instead of information about the location of the experiment, which is irrelevant in this case.
In the "Statistical analysis" section, change the numbering to "2.7. Statistical analysis."
The designation "Figure 1" is repeated in lines 141 and 159, correct to "Figure 2."
Correct the figure numbering in lines 172, 302, 320 to "Figure 3," "Figure 4," and "Figure 5," respectively.
In lines 301 and 389, describe the meaning of the various "*" symbols in the "Figure 3" and "Figure 6" diagrams.
In the text, use a period as a decimal separator, according to editorial requirements, instead of the comma used in tables.
Author Response
Please find attached the answers provided
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsOverall, the paper has seen significant improvements, with many experimental details supplemented and expressions made more accurate. However, there are still some issues, as follows:
The paper does not clarify how the TAN in the nutrient solutions (both before dilution and during cultivation) is adjusted. Is the target TAN achieved through dilution or by supplementing ammonia nitrogen?
In Table B.2, why are there data for day 14 in T2 and T3, rather than day 21? Why did the TAN on day 14 increase sharply compared to day 7? Additionally, where are the data for T4?
Comments for author File: Comments.pdf
Author Response
Hello,
Thank you for correcting our article. Please find attached the answers to comments.
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authorssee below!
Comments on the Quality of English LanguageThe authors have improved the paper according to the recommendations. Although I have some doubts that the accessability of liquid chicken manure is as high as reported I recommend - acceptance- now.
Author Response
Hello,
Thank you for correcting our article. Please find attached the answers to the comments.
Author Response File: Author Response.pdf
