Carbon Life Cycle Assessment on California-Specific Wood Products Industries: Do Data Backup General Default Values for Wood Harvest and Processing?
Round 1
Reviewer 1 Report
Line 14 and 32 - Unnecessary copy of the sentence.
Line 14-63 -There is no clear definition of the purpose in the abstract or introduction.
Line 31-63 - Literature references are not properly formatted
Line 59-60, 107, 145-146, 158-159, 164 - some of references are missing
Line 66- „In 2016, we surveyed three large commercial sawmill owners who process sawlogs from their own timberlands.” The study basis only on three sawmill owners. It is the statistical minimum. It's hard to imagine the normal distribution from only three sources. The number of survey should be definitely increased or please explain what kind of survey it was (how many question, etc.).
65 - What kind of program or database was used? (OpenLCA?). Was everything counted manually?
104 - Nothing has been discussed - The results and discussion are in one chapter. Only the factors and numerical values from the annuals are presented.
line 115-117 - The authors should propose a wider use of logging residues than leaving or burning them on site. I propose to discuss this with reference to the articles:
Nurek, T., Gendek, A., & Roman, K. (2018). Forest Residues as a Renewable Source of Energy: Elemental Composition and Physical Properties. BioResources, 14(1), 6-20. Retrieved from https://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_14_1_6_Nurek_Forest_Residues_Renewable_Energy/6480
Tomasz Nurek, Arkadiusz Gendek, Kamil Roman, Magdalena Dąbrowska, 2019, The effect of temperature and moisture on the chosen parameters of briquettes made of shredded logging residues, Biomass and Bioenergy, Volume 130, 105368, ISSN 0961-9534, https://doi.org/10.1016/j.biombioe.2019.105368.
https://www.researchgate.net/publication/336069550_The_effect_of_temperature_and_moisture_on_the_chosen_parameters_of_briquettes_made_of_shredded_logging_residues
Especially burning them on the site increases CO2 emissions, LCA was specifically devised to prevent such practices
The notion of Life Cycle Analysis is mainstream in the energy efficiency literature, but I cannot find any reference on this issue in the paper. If the authors cannot or do not think necessary, they need to justify or recognise it in the limits of the study proposing further research in the future. There are not many, however there are published works on this topic, for example see:
Konieczna, A.; Roman, K.; Roman, M.; Śliwiński, D.; Roman, M. Energy Efficiency of Maize Production Technology: Evidence from Polish Farms. Energies 2021, 14, 170.
Line 170 - The table was not discussed.
Line 260 - Should be put some conclusion, what follows from LCA analysis. This is required by the manuscript title.
Author Response
Reviewer 1
Line 14 and 32 - Unnecessary copy of the sentence.
Done – Line 14 reworded
Line 14-63 -There is no clear definition of the purpose in the abstract or introduction.
Done – Abstract contains now a goal statement starting line19. The goal statement in the introduction is in line 57
Line 31-63 - Literature references are not properly formatted
Done – We checked the references between line 31-63 and could not find a formatting problem. There was one error message in line 60 that cross-reverenced Figure 1. That has been fixed.
Line 59-60, 107, 145-146, 158-159, 164 - some of references are missing
Done:
Line 59 missed a cross-reference to Figure 1
Line 109 missed a cross-reference to Table 1
Line 147 missed a cross-reference to section ‘Slash: fate and fossil fuel use’
Line 161 missed a cross-reference to Table 2
Line 166 missed a cross-reference to Table 2
Line 66- „In 2016, we surveyed three large commercial sawmill owners who process sawlogs from their own timberlands.” The study basis only on three sawmill owners. It is the statistical minimum. It's hard to imagine the normal distribution from only three sources. The number of survey should be definitely increased or please explain what kind of survey it was (how many question, etc.).
Done – We added ‘at 11 sawmill sites’ to clarify that this is not just three sawmills but a lot of sites. We explained (and still explain) this in more detail in the results section 3.2 but understand that it creates confusion in section 2 if there no basic information is provided.
65 - What kind of program or database was used? (OpenLCA?). Was everything counted manually?
Done – Starting in line 72 we added the following sentence: ‘Since the purpose of the study was to test standardized inputs and assumptions, all inputs relied on manual entries and no LCA database or program was used.’
104 - Nothing has been discussed - The results and discussion are in one chapter. Only the factors and numerical values from the annuals are presented.
Previously addressed. We represent results and discussion in a joint section 3 as this format lend itself to the study and is the recommended format from the journal’s template. Section 3.1 provides an overview on the results only. Subsequently, we discuss the results in depth with other relevant literature. This entails a discussion in comparison to previous California based sawmill surveys (see e.g. section 3.2), in comparison to other sources regarding harvest operations (section 3.3.1), sawlog transport (section 3.3.2) energy requirements at the sawmill sites (section 3.3.3)
line 115-117 - The authors should propose a wider use of logging residues than leaving or burning them on site. I propose to discuss this with reference to the articles:
Done - We added a reference to value-added products from slash as a future opportunity in line 148. For clarification, it is true that some of the slash is burned on site but we also reported that a substantial portion of slash is being used to generate electricity (e.g. line 117; line 144 and following).
Nurek, T., Gendek, A., & Roman, K. (2018). Forest Residues as a Renewable Source of Energy: Elemental Composition and Physical Properties. BioResources, 14(1), 6-20. Retrieved from https://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_14_1_6_Nurek_Forest_Residues_Renewable_Energy/6480
Tomasz Nurek, Arkadiusz Gendek, Kamil Roman, Magdalena Dąbrowska, 2019, The effect of temperature and moisture on the chosen parameters of briquettes made of shredded logging residues, Biomass and Bioenergy, Volume 130, 105368, ISSN 0961-9534, https://doi.org/10.1016/j.biombioe.2019.105368.
https://www.researchgate.net/publication/336069550_The_effect_of_temperature_and_moisture_on_the_chosen_parameters_of_briquettes_made_of_shredded_logging_residues
Especially burning them on the site increases CO2 emissions, LCA was specifically devised to prevent such practices
The notion of Life Cycle Analysis is mainstream in the energy efficiency literature, but I cannot find any reference on this issue in the paper. If the authors cannot or do not think necessary, they need to justify or recognise it in the limits of the study proposing further research in the future. There are not many, however there are published works on this topic, for example see:
Konieczna, A.; Roman, K.; Roman, M.; Śliwiński, D.; Roman, M. Energy Efficiency of Maize Production Technology: Evidence from Polish Farms. Energies 2021, 14, 170.
Line 170 - The table was not discussed.
Done – Table 2 is discussed in section 3.2 but the cross-reference linking failed and produced an error message. We fixed this formatting issue, there is a clear reference to Table 2 in the text now.
Line 260 - Should be put some conclusion, what follows from LCA analysis. This is required by the manuscript title.
Done – We added a conclusion section (section 5).
Reviewer 2 Report
The authors updated the dataset of the wood products industry (sawmills) in California for analyzing carbon life cycle assessment. With the development of innovative technologies, the efficiency and energy consumption of wood product processing have been improved and reduced, respectively. It is time to revisit the tables and make revisions.
It is a well-written manuscript in terms of goals and objectives, accuracy of data acquired. I would like to suggest the authors double-check the references inserted in the main body of the manuscript and use the correct number to replace this message of (Error! Reference 59 source not found.).
In Table 2, the column of "Species": please add the scientific name of the species in brackets next to the commercial name.
Also, it would be nice if a "Conclusion" section can be added after section 3. Results and Discussion.
Author Response
Reviewer 2
The authors updated the dataset of the wood products industry (sawmills) in California for analyzing carbon life cycle assessment. With the development of innovative technologies, the efficiency and energy consumption of wood product processing have been improved and reduced, respectively. It is time to revisit the tables and make revisions.
It is a well-written manuscript in terms of goals and objectives, accuracy of data acquired. I would like to suggest the authors double-check the references inserted in the main body of the manuscript and use the correct number to replace this message of (Error! Reference 59 source not found.).
Done – All error references are fixed and related back to cross-referenced Tables and Figures.
In Table 2, the column of "Species": please add the scientific name of the species in brackets next to the commercial name.
Done – We added scientific/Latin names.
Also, it would be nice if a "Conclusion" section can be added after section 3. Results and Discussion.
Done – We added a conclusion section (section 5).
Round 2
Reviewer 1 Report
The manuscript was properly prepared and I have no comments about it. The authors took into account all suggestions for improvement.
