An Assessment of Two Types of Industrially Produced Municipal Green Waste Compost by Quality Control Indices
Peter Von Fragstein
Round 1
Reviewer 1 Report
Reviewer: This paper evaluated the quality of two kinds of industrial composts by comparing their physicochemical properties, hygienic safety, fertilization potential and heavy metal pollution potential. The following are my critical comments for the submitted manuscript which need attention.
Detailed Comments:
1. There is a lack of discussion about seed germination index and the index of humic acid detection.
2. Please revise the grammar of the introduction, it is confusing.
3. How to sample？ Please describe in detail. What is the depth?
4. Please pay attention to verb tenses：Line 291, Line 294, Line 310 and so on.
Author Response
The authors of the article thank the reviewer for professional and constructive suggestions for improving the manuscript, as well as for correcting some errors and inaccuracies. In order to clarify the information provided, we have made revisions as reviewer recommended. The revisions were highlighted by using the "Track Changes" function in Microsoft Word, so that changes are easily visible. Our detailed explanations, point by point are as follows:
Point 1: There is a lack of discussion about seed germination index and the index of humic acid detection.
Response 1: The aim of this study was to make a quality assessment of the produced composts by means of fertilizing index (FI) and clean index (CI) using parameters included in Bulgarian and EU legislation. The seed germination index and the index of humic acid detection are not among them.
Point 2: Please revise the grammar of the introduction, it is confusing.
Response 2: The grammar of the introduction was revised. We hope we have achieved the desired result. All changes are visible in the revised version of the manuscript.
Point 3: How to sample? Please describe in detail. What is the depth?
Response 3: A text was added to clarify at what depth the compost samples were taken for testing - approximately 200 g spot sample was taken at 5 cm from the surface and at 20 cm from the bottom level from all 12 sample sites of each of the both windrows.
Point 4: Please pay attention to verb tenses: Line 291, Line 294, Line 310 and so on.
Response 4: Apart in the above mentioned lines, grammatical corrections have been made throughout the manuscript. All changes are visible in the revised version of the manuscript.
Reviewer 2 Report
The manuscript is well synthesized, clear, and accurately structured. I do not find any major or minor flaws in content, structure, scientific presentation, or logical arguments to support the findings.
Author Response
The reviewer there is no comments and suggestions for authors. We thank for it positive assessment of the article.
Reviewer 3 Report
Please look into uploaded file
Comments for author File: 
Comments.pdf
Author Response
The authors of the article thank the reviewer for professional and constructive suggestions for improving the manuscript, as well as for correcting some errors and inaccuracies. In order to clarify the information provided, we have made revisions as reviewer recommended. The revisions were highlighted by using the "Track Changes" function in Microsoft Word, so that changes are easily visible. On the comments and suggestions for authors, presented in a table our responses are as follows:
Point 1: Line 69, old: …An extensive researches…; Change proposal: …An extensive research…
Response 1: Changed as suggested
Point 2: Line 128, old: …R1, capacity – 292,254.2 t and R2, capacity – 157,102 t),
Response 2: Changed: …R1, capacity – 292,254.2 t and R2, capacity – 157,102 t), …
Point 3: Line 129/130, old: … 30 000 t/y and … up to 2756 t/y …
Response 3: Changed: … 30 000 t y-1 and … up to 2756 t y-1 …
Point 4: Line 196, old: … mg.kg-1…
Response 4: Changed: … mg kg-1…
Point 5: Line 253, old:
Table 2
header: … mg.kg-1…;
line 3 No 3: all figures only with one decimal
Response 5: Changed as suggested
Point 6: Line 297, old:
Table 3
No 3 mS.cm-1
No 13 – 19 mg.kg-1
No 20 CFU / g
No 21 CFU / 25g
Response 6: Changed:
Table 3
No 3 mS cm-1
No 13 – 19 mg kg-1
No 20 CFU g-1
No 21 CFU 25g-1
Point 7: Line 307, old: …mS.cm-1…
Response 7: Changed: …mS cm-1…
Point 8: Line 316, old: …mS.cm-1…
Response 8: Changed: …mS cm-1…
Point 9: Line 384, old: Organic elements ratios
Response 9: Changed: Carbon ratios
Point 10: Line 428/429, old: …mg.kg-1…
Response 10.: Changed: …mg kg-1…
Point 11: Line 466, old: CFU / g
Response 11: Changed: CFU g-1
Point 12: Line 483, old: C2compost
Response 12: Changed: C2 compost
Point 13: Line 521/524, old: …mg.kg-1…
Response 13: Changed: …mg kg-1…
Point 14: References, old: Bioresour. Technol., Waste Manag.
Response 14: The proposed changes were made everywhere in the list of references -Bioresource Technol., Waste Manage.
Reviewer 4 Report
The purpose of this article is to study the evaluation of two types of compost from industrial green waste in terms of quality control, which is undoubtedly an urgent task, the solution of which contributes to the achievement of the goals of the circular economy. The article is written in good scientific language, well structured, and the data obtained are adequately described. A lot of qualified work has been done, so I propose to accept the article in present form.
Author Response
The reviewer has no comments and suggestions for authors. We thank for his positive assessment of the article.
Reviewer 5 Report
The authors propose an interesting comparison between two types of industrial compost. In both, there was the predominant presence of green waste. This is one of the most controversial urban waste management due to the heavy metals present in this waste due to the urban environment in which the plants grow. However, these wastes are an important carbon source for biotic industrial processes. The authors demonstrated the possibility of producing good quality compost starting from green waste, demonstrating that the concentration of metals was within the norm. The manuscript can be published after minor amendments. Details are in the attached file.
Comments for author File: Comments.pdf
Author Response
The reviewer has made very relevant editorial notes in the attached file. They are all taken into account and are visible in the revised version of the manuscript.
Point 1: Please, specify the modifications of the culture media used?
Response 1: At the selective enrichment step RVS (RAPPAPORT-VASSILIADIS-Soya, Merck, Germany) broth was used: a modification of the original Rappaport medium, where tryptone was replaced with soya peptone to improve Salmonella recovery rates.
