Carbon Mineralization Dynamics of Organic Materials and Their Usage in the Restoration of Degraded Tropical Tea-Growing Soil

Round 1

Reviewer 1 Report

Dear Authors!

I carefully examined the Manuscript, which you submitted to the Agronomy journal. I find that the topic of the MS is not new, but the results are original and worth consideration. It is relevant for the wide audience of the journal. The quality of the manuscript is appropriate but the language needs a strong revision. It still contains a couple of typos that can be confusing in areas that use different dialects. For example, in line 59: “Tea waste is a waste byproduct of the tea processing system generated about 4-6% of the total made tea production depending on the quality of the leaf.” - Grammar is not correct, please check the sentence construction.
In addition, the introduction does not clearly edited. For example, in line 55 when you mention first the compost, Gliricidia plants, and biochar without any definition or description. 

Methods
The experiment was properly projected and implemented, but the applied analytical and statistical methods are missing. Please explain which statistical test was applied for which data.
Other comments for this chapter:
Please add the grades of the chemicals and their purity.
Why did the authors choose exactly 450°C temperatures for the pyrolyzation?

Result
The results and discussion chapters should be enriched with dose-dependent results of the soil improvers.
Objections:
Put Table 1-2 in this chapter. 
What do you mean under “raw biochar“ and “charged biochar”? Please explain it in the introduction.
In this case, Figure 3 is not informative. Please consider its re-editing.
In the case of Table 5, what are the values of the correlation levels of Pearson coefficients? Are you sure that the 0.452 value is a strong correlation? Please detail the calculation in the methods chapter. One-tailed or two-tailed etc…

Apologies to criticize but this MS needs a strong rework.

Author Response

The file attached in this submission is in the “word tracking”.  Therefore, the line and page are referred to this new file.  Your comments (line and page) are in the original word file.  We copied directly in the column 2 for your perusal.  You can check the correction made by clicking the red vertical line at the left page of manuscript.

Author Response File: Author Response.pdf

Reviewer 2 Report

Scientifically based management of carbon sequestration in soils and incresing of SOM recalcitrance to mineralisation in various natural zone is quite important topic for current soil science and soil ecology. Thus this paper is interesting for broad audience of selceted journal.

Following suggestions are made with aim to increase a quality of paper: 

 

-Abstract - soils A and B - clafiry accodring to WRB - soils designation by letters of alpha bet is not possible. Even if it was one soil, it should be named in Abstract

-Abstract - the working hypothesis is not evident here, just some achievements are described.

-What is "soil quality measure" - fro me it is not clear

-Introduction - I think that it should be starte with problems of soil organic matter stabilization in general, afterwhat the stock of SOM in tropical soils can be discussed with other objects.

-The introduction chapter should e finales not only by formulation of aim, but, also , few more precise objectives,

-MandMs chapter - what is Ap horizon? which classification?

-"soil A and low carbon – soil B"  - you have started from experimental design, but A and B - not cler. Provide more detailed info about soil origin, solum horizontal organisation, regional setting insert map and so on

-"soils were air-dried and sieved through a 2 mm sieve" - question - was it grounded or not? this is quite importan for characterization of further mineralisation

-Fig 3 is not easy to understand what is presented on graphs. need to be imroved.

-"3.44% carbon soil (Siltyclay) " - here I understand, the difference betwenn soils - initial carbon contnet. thus, the density fractionation could help to understand initial recalcitrance of SOM to mineralisation. Do you have any idea on this topic.

-here "Higher CO2 emission recorded in soil A could be attributed to the higher initial organic C content in soil A"  - I agree - but how to characterize initial differences in SOM origin and organic precursors between soils A and B?

-"Many scholars" - many researchers?

-Conclusion "Incorporation of RBC, CBC and compost enrich the soil recalcitrant C pool ensuring the greater potential of restoring the soil health in long term" - this is good working hypothesis, in shoretened form it would be showen in Abstract and in whole text.

-some idea on soil ecosystems services in context of environmental management and suggestions for desigion makers should be provided.

 

 

Author Response

The file attached in this submission is in the “word tracking”.  Therefore, the line and page are referred to this new file.  Your comments (line and page) are in the original word file.  We copied directly in the column 2 for your perusal.  You can check the correction made by clicking the red vertical line at the left page of manuscript.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Generally:

The quality of the MS is highly improved. The introduction is well documented. The methods are clear as well and the results are well-founded. I suggest acceptance after a minor revision.

 

Detailed comments:

Please attach the correlation analysis chapters into one, and put it at the end of the results.

Line 37: please change the „goals” word to „aim”.

Line 73: “Hance” unknown word.

Line 102: The sentence is not readable in the uploaded version.

Line 141: Please delete the duplicate sub-heading.

Line 156: different word type.

Line 207: Please delete the duplicate sentence.

Line 453: „proliferate” is an uncommon word. Please change it.

Line 527: Please detail what type of soil.

If I were to look for the weakness of the manuscript now, I would say that there are few references made in the last years. Therefore, I would suggest to the authors some new references relevant to the topic.

Suggestions

Kocsis, T., Kotroczó, Z., Kardos, L., & Biró, B. (2020). Optimization of increasing biochar doses with soil–plant–microbial functioning and nutrient uptake of maize. Environmental Technology & Innovation, 20, 101191.

Puttaso, P., Namanusart, W., Thumanu, K., Kamolmanit, B., Brauman, A., & Lawongsa, P. (2020). Assessing the Effect of Rubber (Hevea brasiliensis (Willd. ex A. Juss.) Muell. Arg.) Leaf Chemical Composition on Some Soil Properties of Differently Aged Rubber Tree Plantations. Agronomy, 10(12), 1871.

Gaffar, S., Dattamudi, S., Baboukani, A. R., Chanda, S., Novak, J. M., Watts, D. W., ... & Jayachandran, K. (2021). Physiochemical Characterization of Biochars from Six Feedstocks and Their Effects on the Sorption of Atrazine in an Organic Soil. Agronomy, 11(4), 716.

Kotroczó, Z., Juhos, K., Biró, B., Kocsis, T., Pabar, S. A., Varga, C., & Fekete, I. (2020). Effect of detritus manipulation on different organic matter decompositions in temperate deciduous forest soils. Forests, 11(6), 675.

Author Response

Pls see the attachment and also green highlighted text in the main manuscript.

Author Response File: Author Response.pdf