Advances in Biological Nitrogen Removal of Landfill Leachate
Round 1
Reviewer 1 Report
The manuscript is clear, well-written, the scope is defined and the content of the manuscript stays within the defined scope.
The material is easy to understand and the authors have reviewed and compiled the information in a helpful manner. Thus, I find the manuscript suitable for publication.
I have a few editorial comments below:
Line 14. Is the sentence relevant to the world or a specific country?
Line 24. Replace “were” with “are”
Line 65: replace “study” with “review”
Line 77: use ANNAMOX abbreviation
Line 82: Please define nitrosation, I am not familiar with this term. How is it different than nitrification?
Line 84: delete “The following” just call out Table 1. “Table 1 shows…”
Line 89: Table 1. Dominant microbial strains. How important is this column for practical purposes? Operators do not have strong control over bacterial populations, especially when leachate itself contains microbial communities that change with different waste types and age.
Line 101. I see you’ve made some type of statement in an attempt to justify this column, but again, how much control or rather, how often would an operator test for microbical communities? Is that something that should be done more frequently? Is it possible to order these specific microorganisms to populate a reactor?
Line 119: I would delete the adverb “Obviously”. Why is it obvious? Couldn’t the algae and bacteria compete rather than work cooperatively? The authors show in the following statements that it is cooperative but I am not sure it is obvious
Line 203: wouldn’t adding food waste also add significant nitrogen to the system? Not to mention particulates
Author Response
Responses to reviews’ comments
Dear Reviewers,
Many thanks for your comments on our manuscript entitled “Advances in Biological Nitrogen Removal of Landfill Leachate” in Sustainability (Manuscript ID: sustainability-1190005). First of all, we are grateful to the reviewers for constructive, meaningful and excellent comments. We have carefully addressed all comments from the reviewers, and we sincerely believe that these comments served to strengthen and enhance the manuscript considerably. The major additions were highlighted in red. Here we present our revised manuscript which has addressed point-by-point all the comments and suggestions from the reviewers.
Reviewers comments:
The manuscript is clear, well-written, the scope is defined and the content of the manuscript stays within the defined scope.
The material is easy to understand and the authors have reviewed and compiled the information in a helpful manner. Thus, I find the manuscript suitable for publication.
I have a few editorial comments below:
Line 14. Is the sentence relevant to the world or a specific country?
Answer: Thanks for your comments，the sentence in Line 14 is relevant to the world and not only refers to a specific country. Previous studies have reported that population, urbanization, and economic growth will lead to an increase in the amount of solid waste production per capita. This is an increasingly serious global problem, and sanitary landfill is still the main method of disposing of municipal solid waste widely used worldwide, especially in developing and underdeveloped countries. Therefore, the landfill leachate produced by this treatment method is also increasing [1-5].
Line 24. Replace “were” with “are”
Answer: Thanks for your comments, and Line 24 is a format error, and has now been corrected in Line 24.
Line 65: replace “study” with “review”
Answer: Thanks for your comments, and Line 66 is a format error, and has now been corrected in Line 66.
Line 77: use ANNAMOX abbreviation
Answer: Thanks for your comments, taking into account the habit of language, we revised the manuscript and changed “anaerobic ammonium oxidation” to "ANAMMOX" in Line 78. And we have checked the whole manuscript, the rest of the “anaerobic ammonium oxidation” was replaced by its abbreviation (ANAMMOX) except for the first appearance.
Line 82: Please define nitrosation, I am not familiar with this term. How is it different than nitrification?
Answer: Thanks for your comments. The nitrosation reaction is a reaction in which the hydrogen in the molecule of an organic compound is replaced by a nitroso group (-NO). Nitrous acid is commonly used as a nitrosation reagent. Nitrification refers to the reaction in which the hydrogen atoms in the molecules of organic compounds are replaced by nitro groups under the action of nitrating agents such as nitric acid. The definition of nitrosation used in this manuscript refers to the combined process of partial nitrosation and ANAMMOX used in the biological nitrogen removal of landfill leachate. It is to add part of the nitrosation process before the ANAMMOX process. Part of the ammonia nitrogen in the influent is nitrosated into nitrite nitrogen, which produces a suitable ratio of nitrous nitrogen and ammonia nitrogen, while consuming part of the influent organic matter, ensuring the stable operation of the subsequent ANAMMOX.
Line 84: delete “The following” just call out Table 1. “Table 1 shows…”
Answer: Thanks for your comments, and Line 84 is a format error, and has now been corrected in Line 85.
Line 89: Table 1. Dominant microbial strains. How important is this column for practical purposes? Operators do not have strong control over bacterial populations, especially when leachate itself contains microbial communities that change with different waste types and age.
Answer: Thanks for your comments. The basic principle of the traditional biological nitrogen removal is that in the secondary biological treatment process, the organic nitrogen is first converted into ammonia nitrogen, and then the ammonia nitrogen is converted into nitrite and nitrate nitrogen through the action of nitrifying bacteria and denitrifying bacteria, and finally the nitrate nitrogen is transformed into nitrogen through denitrification to complete nitrogen removal.
However, the progress of nitrification and denitrification reactions are mutually restricted. The traditional biological nitrogen removal mainly relies on adjusting the process flow to alleviate the contradiction between the reaction environment of nitrifying bacteria and denitrifying bacteria. This contradiction is not obvious in the treatment of municipal wastewater with low ammonia nitrogen concentration, but when dealing with high-concentration ammonia nitrogen wastewater such as landfill leachate, it greatly limits the nitrogen removal efficiency of the system. Therefore, a variety of new processes have been developed, such as ANAMMOX technology, the combination process of partial nitrification, nitrosation, denitrification and ANAMMOX, biofilm treatment process based on ANAMMOX technology and membrane bioreactor, etc. Among them, microorganisms play an indispensable role in these processes.
It has been shown that the analysis of the structure and function of the microbial community in the nitrogen removal system is important for the management of the bioreactor. Wei et al. studied the effects of microbial community structures in anammox-denitrification process using Illumina MiSeq sequencing and qPCR, and showed that the dominant microbial communities in the ANAMMOX-denitrification reactor of mature landfill leachate with different properties were different, and the nitrogen removal efficiency was different [1]. Wang et al. also showed that the mature leachate with different organic loads, BOD5/TN and NO2-N/NH4-N ratios was positively correlated with ANAMMOX microorganisms, thereby improving nitrogen removal efficiency [6]. Xu et al. found that the highly diverse microbial community in landfill bioreactors could be substantially affected by increasing biodegradable carbon and oxygen content, which led to the whole system’s intrinsic nitrogen removal capacity increasing from 50 to 70 % [3]. Hassan et al. reviewed that alternate aerobic and anaerobic zones for mature leachate create ideal conditions for denitrification and anammox bacteria to help improve nitrogen removal [5]. Wang [7, 8] and Xie [9] et al. analyzed the functional genes and microbial communities in the aging refuse bioreactor and showed that there were various nitrifying bacteria and denitrifying bacteria with different heterotrophic and autotrophic metabolic pathways in the reactor, which proved that the existence of multiple nitrogen removal pathways, thus providing important information for the management of nitrogen in landfill sites. Wei et al. showed that the spatial distribution and diversity of the microbial community could reflect the microbial ecological mechanism of organic matter removal efficiency, and thus optimize the operating conditions to quickly start the landfill bioreactor [10].
In conclusion, the analysis of microbial community structure in landfill bioreactor and its evolution process can help to link functional (microbial) communities and genes with nitrogen removal activities, thus determining nitrogen metabolism pathways and their corresponding activities at different operating stages, and laying a foundation for the improvement of reactor performance. In addition, it may be an important step for leachate management and treatment to study the functional bacterial community and reveal the mechanism and practical application of various process reactors.
Therefore, the operator can effectively control the bacterial population for different types of landfill leachate in future practical applications, thus improving the nitrogen removal performance by analyzing the microbial community and the mechanism of various process reactors.
Line 101. I see you’ve made some type of statement in an attempt to justify this column, but again, how much control or rather, how often would an operator test for microbical communities? Is that something that should be done more frequently? Is it possible to order these specific microorganisms to populate a reactor?
Answer: Thanks for your comments. As mentioned in the previous question, the functional microbial flora plays an important role in the nitrogen removal of the landfill leachate. It may be an important step for leachate management and treatment to study the functional bacterial community and reveal the mechanism and practical application of various process reactors. Regarding the reviewer’s question “how much control or rather, how often would an operator test for microbial communities? Is that something that should be done more frequently?”, the following information can be obtained through referencing to the literature. The biological nitrogen removal of landfill leachate is carried out by the combination of multiple processes or reactors, and there are different operating stages and operating conditions in this process [1, 11]. Therefore, the monitoring of the microbial community is carried out at the completion of different operation stages [1, 6, 7]. At the same time, the microbial community is constantly changing and enriching, so sampling and monitoring should be carried out at the stable period of each operation stage [3, 6, 7]. In addition, the analysis of microbial community structure in landfill bioreactor and its evolution process can help to link functional (microbial) communities and genes with nitrogen removal activities, thus determining nitrogen metabolism pathways and their corresponding activities at different operating stages, and laying a foundation for the improvement of reactor performance. Therefore, the microbial community plays an indicator role, and more and more studies have been conducted on the diversity of microorganisms in different processes. Just as the reviewer proposed whether it is possible to order these specific microorganisms to populate a reactor in the future, this is also the significance of our review and the prospect of the future. The functional microflora of representative processes was summarized to provide support information for the subsequent improvement of process performance, and it was proposed that more attention should be paid to the dynamic changes of microbial strains in the subsequent studies from the perspective of microorganisms to improve the efficiency of nitrogen removal.
Line 119: I would delete the adverb “Obviously”. Why is it obvious? Couldn’t the algae and bacteria compete rather than work cooperatively? The authors show in the following statements that it is cooperative but I am not sure it is obvious
Answer: Thanks for your comments, I'm sorry that there is an ambiguity of the adverb "obviously" due to insufficient information. So we provided detailed information in the revised manuscript in Line 140-145. As the reviewer said and we mentioned in the manuscript, cultivating microalgae in landfill leachate is a viable bioremediation option because they can remove nutrients, mainly ammonia nitrogen and other pollutants. At the same time, other microorganisms in the landfill leachate, such as bacteria, can co-exist with the microalgae to form a microalgae-bacterial combination, and jointly carry out biological treatment of the landfill leachate. In fact, we use the adverb "obviously" here to show that the co-treatment of microalgae and bacteria has a more obvious efficiency of nitrogen removal than the treatment of landfill leachate by microalgae alone. However, the specific values for comparison may not be given in the manuscript, which aroused the doubts of the reviewer. In the revision, we compared the literatures about nitrogen removal of landfill leachate on single treatment by microalgae and co-treatment by microalgae and bacteria in more detail, and the effect of co-treatment was significantly improved compared with that of single treatment. Previous studies have shown that removal of ammonia nitrogen by microalgal assimilation can remove 65-85% of nitrogen from leachate during growth and deposition of organic nitrogen in a stabilizer tank [12]. A microalgae-bacteria consortium has removed 90% of total nitrogen in 10% landfill leachate [13]. Therefore, we provided detailed information in the revised draft in Line 140-145 in combination with the comment of reviewer to avoid ambiguity.
Line 203: wouldn’t adding food waste also add significant nitrogen to the system? Not to mention particulates
Answer: Thanks for your comments, as the reviewer said, adding food waste would also add significant nitrogen to the system. Therefore, food waste with high C/N ratio and low nitrogen content should be selected as far as possible in the biological nitrogen removal of landfill leachate. The main purpose is to provide carbon sources for denitrification to speed up the denitrification process. For example, an acid-producing liquid can be selected from the intermediate product produced by the fermentation of food waste, and its components mainly include volatile fatty acids, ethanol and soluble proteins. Moreover, it is relatively easy to control only hydrolysis and acidification in the anaerobic fermentation process of food waste to obtain high-quality carbon sources for denitrification. Previous studies have shown that it can improve the efficiency of nitrogen removal to add fermentation liquid of food waste as an external carbon source in the nitrogen removal bioreactor. Tang et al. used fermentation liquid of food waste (FLFW) as an external carbon source to treat domestic wastewater with low COD/TN ratio in a pilot-scale anoxic/oxic-membrane bioreactor (A/O-MBR) system. The results showed that the total nitrogen removal increased from less than 20% to 44-67% over 150 days of operation with the addition of FLFW [14]. Therefore, we have added instructions in the manuscript in Line 256-267 in order to make the logic more rigorous.
Once again, thank you very much for your comments and suggestions.
Yours sincerely,
Ye Li, Fan Tang, Dan Xu, Bing Xie
Corresponding author: Bing Xie, Professor
Corresponding author at: Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences,
East China Normal University, Shanghai 200241, China.
E-mail address: bxie@des.ecnu.edu.cn (Bing Xie)
References
- Wei, H.; Wang, J.; Hassan, M.; Han, L.; Xie, B., Anaerobic ammonium oxidation-denitrification synergistic interaction of mature landfill leachate in aged refuse bioreactor: Variations and effects of microbial community structures. Bioresource Technology 2017, 243, 1149-1158.http://dx.doi.org/10.1016/j.biortech.2017.07.077
- Hassan, M.; Wang, X.; Wang, F.; Wu, D.; Hussain, A.; Xie, B., Coupling ARB-based biological and photochemical (UV/TiO2 and UV/S2O82-) techniques to deal with sanitary landfill leachate. Waste Management 2017, 63, 292-298.http://dx.doi.org/10.1016/j.wasman.2016.09.003
- Xu, W.; Wu, D.; Wang, J.; Huang, X.; Xie, B., Effects of oxygen and carbon content on nitrogen removal capacities in landfill bioreactors and response of microbial dynamics. Applied Microbiology and Biotechnology 2016, 100, (14), 6427-6434.http://dx.doi.org/10.1007/s00253-016-7460-5
- Wu, D.; Wang, T.; Huang, X.; Dolfing, J.; Xie, B., Perspective of harnessing energy from landfill leachate via microbial fuel cells: novel biofuels and electrogenic physiologies. Applied Microbiology and Biotechnology 2015, 99, (19), 7827-7836.http://dx.doi.org/10.1007/s00253-015-6857-x
- Hassan, M.; Xie, B., Use of aged refuse-based bioreactor/biofilter for landfill leachate treatment. Applied Microbiology and Biotechnology 2014, 98, (15), 6543-6553.http://dx.doi.org/10.1007/s00253-014-5813-5
- Wang, X. Y.; Xie, B.; Zhang, C. Q.; Shen, Y. W.; Lu, J., Quantitative impact of influent characteristics on nitrogen removal via anammox and denitrification in a landfill bioreactor case. Bioresource Technology 2017, 224, 130-139.http://dx.doi.org/10.1016/j.biortech.2016.11.078
- Wang, C.; Zhao, Y. C.; Xie, B.; Peng, Q.; Hassan, M.; Wang, X. Y., Nitrogen removal pathway of anaerobic ammonium oxidation in on-site aged refuse bioreactor. Bioresource Technology 2014, 159, 266-271.http://dx.doi.org/10.1016/j.biortech.2014.02.093
- Wang, C.; Xie, B.; Han, L.; Xu, X. F., Study of anaerobic ammonium oxidation bacterial community in the aged refuse bioreactor with 16S rRNA gene library technique. Bioresource Technology 2013, 145, 65-70.http://dx.doi.org/10.1016/j.biortech.2013.01.170
- Xie, B.; Xiong, S. Z.; Liang, S. B.; Hu, C.; Zhang, X. J.; Lu, J., Performance and bacterial compositions of aged refuse reactors treating mature landfill leachate. Bioresource Technology 2012, 103, (1), 71-77.http://dx.doi.org/10.1016/j.biortech.2011.09.114
- Wei, H. W.; Wang, X. Y.; Hassan, M.; Huang, H.; Xie, B., Strategy of rapid start-up and the mechanism of de-nitrogen in landfill bioreactor. Journal of Environmental Management 2019, 240, 126-135.http://dx.doi.org/10.1016/j.jenvman.2019.03.111
- Xie, B.; Lv, Z.; Hu, C.; Yang, X. Z.; Li, X. Z., Nitrogen removal through different pathways in an aged refuse bioreactor treating mature landfill leachate. Applied Microbiology and Biotechnology 2013, 97, (20), 9225-9234.http://dx.doi.org/10.1007/s00253-012-4623-x
- Martins, C. L.; Fernandes, H.; Costa, R. H. R., Landfill leachate treatment as measured by nitrogen transformations in stabilization ponds. Bioresource Technology 2013, 147, 562-568.http://dx.doi.org/10.1016/j.biortech.2013.08.085
- Zhao, X.; Zhou, Y.; Huang, S.; Qiu, D. Y.; Schideman, L.; Chai, X. L.; Zhao, Y. C., Characterization of microalgae-bacteria consortium cultured in landfill leachate for carbon fixation and lipid production. Bioresource Technology 2014, 156, 322-328.http://dx.doi.org/10.1016/j.biortech.2013.12.112
- Tang, J. L.; Wang, X. C. C.; Hu, Y. S.; Ngo, H. H.; Li, Y. Y.; Zhang, Y. M., Applying fermentation liquid of food waste as carbon source to a pilot-scale anoxic/oxic-membrane bioreactor for enhancing nitrogen removal: Microbial communities and membrane fouling behaviour. Bioresource Technology 2017, 236, 164-173.http://dx.doi.org/10.1016/j.biortech.2017.03.186
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This manuscript aimed at reviewing Advances in Biological Nitrogen Removal of Landfill. The topic for this is currently relevant. However, this manuscript has several major issues.
- The language used in this paper needs extensive review.
- There are several instances in sections 1 and 2, the authors haven't been able to cite relevant references for the statements and arguments.
- But the main issue with this manuscript is the lack of breadth in the review. For example, in section 2.2.1, the authors unable to cite all the relevant papers published in the area. There are close to 22 papers published on this particular section over the last few years, however the authors only able to reference 5-6 papers in this section.
Author Response
Responses to reviews’ comments
Dear Reviewers,
Many thanks for your comments on our manuscript entitled “Advances in Biological Nitrogen Removal of Landfill Leachate” in Sustainability (Manuscript ID: sustainability-1190005). First of all, we are grateful to the reviewers for constructive, meaningful and excellent comments. We have carefully addressed all comments from the reviewers, and we sincerely believe that these comments served to strengthen and enhance the manuscript considerably. The major additions were highlighted in red. Here we present our revised manuscript which has addressed point-by-point all the comments and suggestions from the reviewers.
Reviewers comments:
This manuscript aimed at reviewing Advances in Biological Nitrogen Removal of Landfill. The topic for this is currently relevant. However, this manuscript has several major issues.
- The language used in this paper needs extensive review.
Answer: Thanks for your comments, by scanning the full manuscript, we have tried our best to correct the grammatical mistakes and beautified the language. For example, we changed “according to statistics” to “It is reported that” in Line 43, “instead” to “In compost” in Line 56 and so on.
- There are several instances in sections 1 and 2, the authors haven't been able to cite relevant references for the statements and arguments.
Answer: Thanks for your comments, we have supplemented relevant references for the statements and arguments in section 1 and 2. For example, in section 2.4.4, there were arguments about the application of Microbial Fuel Cell in nitrogen removal of leachate. So we added some papers which supported this statement in Line 339-340. And we also supplemented some references in other sections to complete our manuscript, and detailed information was highlighted in red in the revised manuscript.
- But the main issue with this manuscript is the lack of breadth in the review. For example, in section 2.2.1, the authors unable to cite all the relevant papers published in the area. There are close to 22 papers published on this particular section over the last few years, however the authors only able to reference 5-6 papers in this section.
Answer: Thanks for your comments, we have supplemented relevant and latest references in this manuscript, and detailed information was highlighted in red in the revised manuscript. For example, in section 2.2.1, we searched the relevant papers with “nitrogen removal”, “leachate” and “Algae bacteria” as the key words. By screening all the results, we added some papers which were more closely related to the topic of the co-cultivation of microalgae and bacteria system in Line 135-145 and 164-175.
Once again, thank you very much for your comments and suggestions.
Yours sincerely,
Ye Li, Fan Tang, Dan Xu, Bing Xie
Corresponding author: Bing Xie, Professor
Corresponding author at: Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences,
East China Normal University, Shanghai 200241, China.
E-mail address: bxie@des.ecnu.edu.cn (Bing Xie)
Author Response File: 
Author Response.docx
Reviewer 3 Report
The Authors describe important issues and the article „Advances in Biological Nitrogen Removal of Landfill Leachate” will be of interest to the readers of "Sustainability". The article would be more valuable if with each method basic information about the leachate, (e.g. pH, redox potential, concentrations of nitrogen compounds, sum of dissolved components, etc.,) were added. This would make it easier for the reader to assess the effectiveness of the method depending on the degree of contamination of the leachate with nitrogen compounds. It would also facilitate the possible choice of the method in one's own case.
In the end of the manuscript, it is worth summarizing under what conditions the method can be used, i.e. the leachate parameters (as above) and the type of the landfill (size, age, amount of waste). I would expect the above-mentioned information as a reader of this article. I suggest adding them.
Author Response
Responses to reviews’ comments
Dear Reviewers,
Many thanks for your comments on our manuscript entitled “Advances in Biological Nitrogen Removal of Landfill Leachate” in Sustainability (Manuscript ID: sustainability-1190005). First of all, we are grateful to the reviewers for constructive, meaningful and excellent comments. We have carefully addressed all comments from the reviewers, and we sincerely believe that these comments served to strengthen and enhance the manuscript considerably. The major additions were highlighted in red. Here we present our revised manuscript which has addressed point-by-point all the comments and suggestions from the reviewers.
Reviewers comments:
The Authors describe important issues and the article „Advances in Biological Nitrogen Removal of Landfill Leachate” will be of interest to the readers of "Sustainability". The article would be more valuable if with each method basic information about the leachate, (e.g. pH, redox potential, concentrations of nitrogen compounds, sum of dissolved components, etc.,) were added. This would make it easier for the reader to assess the effectiveness of the method depending on the degree of contamination of the leachate with nitrogen compounds. It would also facilitate the possible choice of the method in one's own case.
In the end of the manuscript, it is worth summarizing under what conditions the method can be used, i.e. the leachate parameters (as above) and the type of the landfill (size, age, amount of waste). I would expect the above-mentioned information as a reader of this article. I suggest adding them.
Answer: Thanks for your comments. In this paper, basic leachate information (such as pH value, COD concentration, total nitrogen content, etc.) has been added for each nitrogen removal method. And the efficiency of nitrogen removal and dominant microbial strains in different processes and reactors shown in Table 1 has been added the basic properties of leachate for each nitrogen removal process. After the table, leachate has been divided into young leachate, intermediate leachate and old leachate according to the standards of COD concentration and pH value, and then the optional process for different types of leachate nitrogen removal has been summarized in Line 93-109. Similarly, in the nitrogen removal process combined with ecological or other solid wastes and in microbiological processes for direct nitrogen removal of Leachate, the relevant properties of leachate have been added accordingly. And detailed information was highlighted in red in the revised manuscript. At the end of the paper, what types of nitrogen removal processes can be selected for leachate with different landfill ages and properties have been summarized in Line 433-448. Hopefully, these changes would make it easier for the reader to assess the effectiveness of the method depending on the degree of contamination of the leachate with nitrogen compounds. It would also facilitate the possible choice of the method in one's own case.
Once again, thank you very much for your comments and suggestions.
Yours sincerely,
Ye Li, Fan Tang, Dan Xu, Bing Xie
Corresponding author: Bing Xie, Professor
Corresponding author at: Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences,
East China Normal University, Shanghai 200241, China.
E-mail address: bxie@des.ecnu.edu.cn (Bing Xie)
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Minor language enhancements required.
Author Response
Dear Reviewers,
Many thanks for your comments on our manuscript entitled “Advances in Biological Nitrogen Removal of Landfill Leachate” in Sustainability (Manuscript ID: sustainability-1190005). First of all, we are grateful to the reviewers for constructive, meaningful and excellent comments. We have carefully addressed all comments from the reviewers, and we sincerely believe that these comments served to strengthen and enhance the manuscript considerably. The major additions of this modification were highlighted in blue. Here we present our revised manuscript which has addressed point-by-point all the comments and suggestions from the reviewers.
Reviewers comments:
Minor language enhancements required.
Answer: Thanks for your comments, we have carefully revised the manuscript according to the reviewers' comments, and also have re-scrutinized to improve the English. We have tried our best to correct the grammatical mistakes and beautified the language in the revised manuscript. The major additions of this modification were highlighted in blue.
Once again, thank you very much for your comments and suggestions.
Yours sincerely,
Ye Li, Fan Tang, Dan Xu, Bing Xie
Corresponding author: Bing Xie, Professor
Corresponding author at: Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences,
East China Normal University, Shanghai 200241, China.
E-mail address: bxie@des.ecnu.edu.cn (Bing Xie)
Author Response File: Author Response.pdf
