Characterisation of Chamaecytisus tagasaste, Moringa oleifera and Vachellia karroo Vermicomposts and Their Potential to Improve Soil Fertility

Round 1

Reviewer 1 Report

It is an interesting article on the current and important topic related to the improvement of soil fertility in agroforestry.

The purpose of the work was clearly defined at the end of the Introduction chapter. The layout of the manuscript is correct, the article has been divided into four main chapters (Introduction, Materials and Methods, Results and Discussion, Conclusions) and sub-chapters. The authors made the correct selection of literature (78 items). Appropriate research methods were used. The research results were presented in a logical and understandable way and compared with the results obtained by other researchers (chapter Results and Discussion).

I would only suggest extending the chapter Conclusions with my own recommendations regarding the practical use of the research results obtained (how could stakeholder groups use these research results), which would result in obtaining a more utilitarian nature of the work.

Author Response

See attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

The study focuses on using common agroforestry species for vermicompost to determine if the vermicompost could be a soil fertility amendment. The potential to be used for a soil fertility amendment was determined via nutrient analysis, biological growth (micro and macro), humic and fulvic acids, and phytotoxicity. Depending on feedstock, the authors found macronutrients and some micronutrients to increase, while others decreased. They also found the earthworm populations to increase in all feedstocks and found the vermicompost to not be toxic via seed germination tests. The authors conclude with vermicompost having the potential to be a useful soil fertility amendment.

I found this study to be very interesting and important as we are facing a global food insecurity crisis as well as an invasive species invasion. However, as the paper stands, I think there is a lot of work that needs to be done to make it readable. There are many instances of incomplete thoughts and inconsistent writing (e.g. use C or carbon throughout, there was one sentence that used both). The paper needs to be spell (V. karroo is misspelled multiple times) and grammar checked as well as go through a thorough check for italics and consistencies (e.g. once you introduce a species (Moringa oleifera, you can call it M. oleifera for the rest of the paper – this is very inconsistent throughout). In addition, there are many sentences that just do not make sense.

Another issue I have with this paper is the statistics. I am concerned about the repeated measures analysis, especially for the information in Table 6. The analysis lacks the interaction of feedstock and time. For example, it seems microbial populations were measured biweekly (although I am unsure of this as the methods do not specifically say), but the feedstocks are only compared once (not sure at which time), but not over time.

Table headings and figure captions need to be looked over again as well. The headings and captions are too vague.

I am also not sure of the use of having supplemental tables if they are not mentioned in the paper. I also think that the PCA graphics (Figures 1, 2, and 3) are not necessary in the main body of the paper, but could go into the supplemental area.  

Specific line comments/suggestions:

L19-L20: Species names in italics

L24. Oleifera should not be capitalized (species) and it all should be in italics

L26. Molybdenum should be Mo to stay consistent with the rest of the elements

L28. Italics for Eisenia fetida

L28. Add an “a” between than and 450%

L29. Delete “the”

L37. Reportedly? This is confusing

L37-L39. Verb tense of this sentence is inconsistent.

L43. The system – do you mean agroforestry?

L48. Can you expand on the passive systems?

L49-L50 (and other locations). When scientific names are mentioned for the first time, the author needs to get credit. For example, Faidherbia albida should be Faidherbia albida ((Delile) A. Chev).

L49. Do you mean Sesbania seban and not Sesbania, sesban?

L58. Chamaecytisus tagaste has already been mentioned, so it can be C. tasgate from here on out.

L59. Odd spacing between words.

L63-L64. You claim that “It” (I am assuming vermicompost) reduces harmful effects of waste material – could you expand on this more?

L68. The word acacia should be capitalized.

L68-69. The sentence starting with In this study,… does not fit here. The sentence also is incomplete, and their potential as soil fertility amendment were what?

L71. Put an “are” before widespread

L74. Can you expand on how this tree has a multiplicity of uses for agroforestry and provide citations?

L77. Delete “on the other hand” and remove the genus name. Watch the spacing.

L80-L82. While this study… sentence is in a different font and is out of place. It belongs in the conclusion or not at all.

L90-95. The collection description is confusing. V. karroo can from the farm but the others are from neighbors? How can the trees be collected at Limpopo, but from other farms? How far away were the neighbors? When were the trees collected – (e.g. summer 2014, fall 2017, etc.)?

L91-92. Italics for C. tagataste.

L92. What size was the feedstock chipped to?

L94. Author for the worm scientific name.

L99. The study was conducted under ambient…

L103. What were the boxes made of?

L104. E. fetida

L108. Vermi-box? Consistency is necessary here – use this term in the previous paragraph.

L111-112. If you don’t report leachate results in this paper, why bother mentioning?

L113. What kind of block digester did you use (e.g. Model, company, location)? This needs to be mentioned for any equipment.

L114. Confusing sentence: organic carbon by was estimated by…?

L115. Model, company, and location for pH and EC meters.

L115. You say respectively here, but don’t actually list them in the correct order you started with.

L116. Model, company, and location for spectrophotometer.

L118. Grounded should be ground.

L118. Compost or vermicompost – be consistent.

L135. Phyochemicals is misspelled.

L137…using the method by… - by who (Odebiyi and Sofowora)? You mention the authors in other spots, but not here.

L140. Counts “were” done.

L141. How often did you do the microbiological analyses?

L141. E. coli should be in italics.

L143. Agar should be lower case.

L144-146. More methods details for these microbes (similar to what was mentioned for total bacteria).

L144. CFU is all caps here but throughout the paper it is lowercase, pick one.

L144. E. coli should be in italics.

L145. Phosphate is missing before solubilizing bacteria.

L148. Repeated can be lowercase.

L149. Location of software.

L158. Are you reporting content or concentration, these are two different things and the words seem to be used interchangeably throughout.

L159. Who are the researchers – cite the papers.

L162. Between should be among (when talking about two things, it’s between, when more than two it is among – this occurs throughout the paper).

L168. You mention N, but what about P and K they are important too.

L171. Delete the period after week 6.

L177-L184. What about N in this paragraph? You led with N, but didn’t discuss it!

L182. Wheat straw? In the previous sentence you say it was rice straw.

L189-191. The N discussion should be included when you first mention N in the paragraph above.

L199. On should be in.

L200-201. This is a weird title for this table as I think the table is reporting the nutrient values and not the repeated measures ANOVA results. What are the units? What do the letters mean?

L200. At different times? How about 2 week intervals or biweekly, different times is too vague.

L204. M. oleifera

L204. “way above” – that is not a scientific term.

L207-208. You attribute the higher P to increased phosphatase activity, but how do you know this, you did not measure phosphatase activity nor to you provide a citation.

L208-209. Odd spacing.

L211. B not boron

L213. Spacing after [37].

L221. “basic concentrations” do you mean basic cations?

L227-228. “However, the values observed were still rather too low than expected.” Confusing.

L228-231. Mabapa and Ayisi measured dry biomass – what values did they get? We need this information to “see” the significantly higher amounts compared to those reported here.

L238-239. The sentence, “It has already been observed that vermicompost tend to have higher N levels.” Says who, do you have a citation for this?

L244. M. not Moringa.

L250. Delete the “the” before pH.

L250-251. As pH increases… this sentence is random and does not flow with the paper.

L262. C. not Chamaecytisus

L263. Write out three not 3.

L268. “dominance occurrence” this doesn’t make sense.

L274. Significance should be significant

L275-276. Put V. karroo in italics and spell karroo correctly.

L277. Spell 3 out.

L277. Species is strong influence… - confusing.

L278. The Table 2 title should not be placed here.

Table 2 title. Use italics.

L323. “higher” do you mean highest?

L324. The C what? Concentration?

L324. HA (HA), what is the point of this, they are the same?

L325. TEB?

L327. Higher should be highest

L328. Higher should be highest

L331. The title heading is too vague. What maturity indices did you measure – spell them out. What are the letters (significant differences)?

L337.Did the vermicomposts have too low of a maturity level?

L341. Who reported the results in [50]?

L356-357. Scientific names can be abbreviated.

L373 (Figure 4). This figure has 3 graphs and they are not differentiated. They should be labeled as A, B, and C and the figure caption should describe that. They should also be referred to that in the text.

L373 (Figure 4). I’m unsure of what the y axis label means.

L378. Multiple problems with this sentence – verb tense and spelling.

L382-383. The two sentences are confusing and contradict each other and the table. The table indicates that there is 0 E-coli for V. karroo and C. tagasate.

L391. Eisenia can be E.

L405. Table 6. The title isn’t very descriptive. Also, what about the interaction of time and vermicompost feedstock? How do we know what the fungi count was for V. karroo at week 2?

L427. The result should be results.

L450-451. What is the importance of this sentence? It seems out of place.

L457-458. The section on phytotoxicity is kind of short. Did the phytotoxcity vary among feedstocks? What were the actual results?

L475-476. This sentence is awkward and vermicomposting does not need to be capitalized.

L477. The “a” should be removed.

Author Response

See  attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Thank you for addressing the comments provided by the reviewers.