Prediction of Static Bending Properties of Eucalyptus Clones Using Stress Wave Measurements on Standing Trees, Logs and Small Clear Specimens
Gonzalo P. Cetrangolo
Round 1
Reviewer 1 Report
- The paper has great merit from a technical point of view, as it presents important results for application in the country (Vietnam). However, it was not possible to detect where the scientific contribution of the paper would be, since only known and widely studied methodologies were applied and there is no new or inovative discussion.
- In lines 181 and 182 the authors indicate that they did not find papers related to hardwood species or young trees, but there are many in the literature, so it is necessary for the authors to expand their bibliographic research.
- In line 258 most of the cited articles are not related to the topic discussed in the item. It is necessary to check.
- In lines 292 to 295 the statement is already widely known and published in papers, which are not cited, so that the conclusion seems to be something new proposed by the authors.
- The first conclusion escapes the objective of the paper, which is the link between the use of stress waves to infer MOE and MOR.
Author Response
Dear Reviewer 1,
We thank you for taking time to consider our work. We would like to address your concerns as in the attached file.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The topic is very interesting and the research was very good. There are some minor comments to improve the document.
In line 123 should be mm3 idem in Fig. 1
In Figure 2 the meaning of ****
In Table 3 indicate the meaning of the letters a, b, c….
In line 255 should be SWVT instead of SWVL twice.
Table 7 the meaning of *** or * there is no explanation about what they mean.
In order the better to avoid confusion please use r o R2, but only one of those, therefore it would be easier to compare the results. In Figures 3, 4 and 5 R2 is used. In Fig. 2 it is presented r.
Caption in Figures 3, 4 and 5 may include that the graphs are of all clones specimens.
In line 341 references numbering are not correct. They start in 4 and they should start in 1.
Author Response
Dear Reviewer 2,
We thank you for taking time to consider our work. We would like to address your concerns as in the attached file.
Author Response File: Author Response.docx
Reviewer 3 Report
The overall paper is well written, nevertheless, I recommend the authors review it to fix some editing errors. The authors started by explaining the formation of the forests in Vietnam and pointing out how the forest and their products, mainly wood-based products, impact the country's economy. From that part, they contextualize the issue to be addressed in the paper. The authors aim to understand and analyze by using statistical methodologies the MOR and MOE of trees, logs, and small clear specimens by using the stress wave velocity method. Therefore, I consider this an original and a relevant topic that can be studied and addressed by other research works by applying the methodology used in the manuscript to other wood species.
In addition, among the references cited in the introduction and throughout the manuscript, the authors used some references, whose first author, is also the first author of this current manuscript. They also deal with the topic presented in this paper, the prediction of MOR and MOE values by using stress way velocity using different “elements”, the trees, logs, and small clear specimens.
The reference list shall be reviewed, since it starts with number 4 instead of number 1 since it was the first reference cited in the text, on Line 30.
Line 28: “In Vietnam the shift from harvesting native forest to plantations has occurred” – Although I could understand what the authors meant by writing the first sentence, I kindly recommend writing it because, in the way it is, it seems that some information is missing.
Have other authors used stress wave velocity methodology to determine the strength and stuffiness properties of small clear wood specimens?
As explained by the authors in Line 181, most studies have focused on studying softwoods and analyzing the SWV of logs and trees. Concerning that, it would be important to know to what this fact is due in the authors' opinion. The larger use of these species, which are softwoods, the greater ease of correlating density and measuring mechanical properties from the SWV, or there are other reasons?
Which standard did the authors use for the static bending tests? The authors explain that small clear specimens with a cross-section of 20mm x 20mm were used and a test span of 260mm. For instance, according to ISO 13061-3 (2014), “If the test is combined with the determination of the modulus of elasticity bending, the span shall be 14 times the height of the test piece, in accordance with ISO 13061-4.”. In this case, the test span should be at least 280mm.
I believe the authors might have seen this paper, but I kindly would recommend reading it: “Segregation of Eucalyptus dunnii logs using acoustics” https://doi.org/10.1016/S0378-1127(02)00519-4
Figure 2: There are *** in the value of r. What do they mean?
Lines 178-179: I would suggest the authors state in the Results and Discussion part that the result of r=0.85 is for the used wood species planted in Vietnam under the conditions mentioned earlier.
Table 2: I kindly recommend the authors use the following legend that they used in Table 3 for Table 2 –“ The same alphabet letters used after values indicate no significant differences between radial positions or among provenances based on Tukey’s HSD test at 5%.”.
Since the authors used different statistical tools to analyze the results, for instance, Pearson's correlation coefficient and regression models, would it not be interesting to present the equation to calculate the Pearson's correlation coefficient like the authors did for the regression model in Equation (2)?
How were the models (equations) presented in Tables 6 and 7 established? In other words, did the authors use the least squares technique to determine the linear regression models?
The authors presented the values of the R-squared, which is fine. However, I kindly would like to know why you did not use the adjusted R-squared instead, since it might bring more precision and reliability.
Overall, the discussions presented by the authors are supported by the results they have.
Author Response
Dear Reviewer 3,
We thank you for taking time to consider our work. We would like to address your concerns as in the attached file.
Author Response File: Author Response.docx
Reviewer 4 Report
Comments and Suggestions for Authors:
The authors' goal was to verify the reliability of using of stress waves measurements on standing trees, logs and small clear specimens to prediction mechanical properties of Eucalyptus clones. This is an interesting topic.
Overall, the title, abstract and the keywords correspond to the aims and objectives of the manuscript.
I have a few comments on the manuscript:
Comment 1: The paper needs to be carefully revised to improve terminology.
... acoustic velocity ... is not correct, correct is ... speed of sound.
Speed of sound is speed at which sound waves propagate through different materials.
.... not weight ... but mass...
Comment 2: The reviewer thinks that the authors could add more information into „Introduction” about acoustic methods assessing properties on standing trees before harvest or sorting logs before processing to ensure lumber meets specified mechanical property design values.
Comment 3:
Lines 89 - 90: ... not (1660 89 tree ha-1) but .... (1660 89 tree ha-1).
Comment 4:
Lines 106 -107: .... (SWVT) was assessed by measuring the time of flight between two measurement points
The reviewer thinks that better is …. (SWVT) was calculated as described by Ishiguri et al. [19].
Lines 117: .... by average of five readings of stress wave transmission time between sensors...
The reviewer thinks that better is …. by average of five readings of stress wave propagation time between sensors...
Table 2. ... mising units of SWV...
Table 3: ... AD (g/cm3) ... better is AD (kg/m3)
Line 223: ... the mean magnitude of dynamic ... mean value of dynamic ...
The Conclusion part reflects the main findings of the manuscript.
The References cited are appropriate to the research topic.
The research presented in the article is interesting. It is consistent with the scope of the Forests Journal.
Best regards.
Author Response
Dear Reviewer 4,
We thank you for taking time to consider our work. We would like to address your concerns as in the attached file.
Author Response File: Author Response.docx
Reviewer 5 Report
The topic of the research work and manuscript is interesting, it provides new information and its text is quite well-prepared. However, there are some issues to be addressed towards its quality improvement before its publication.
In line 22, the “was be achieved” should be corrected. In line 57, you refer “wood quality may be an issue”, please provide more details to be more clear. In line 57, probably a preposition is missing contributing to vagueness. Please add the relevant paper entitled “Prospects for the utilization of black locust wood (Robinia pseudoacacia L.) coming from plantations in furniture manufacturing”, in the introduction chapter in the part where you refer to acacia species. I would rather substitute the word “ramet” with another word (probably trunk). You should provide all the necessary details for the equipment used (model, manufacturer, country etc.). Leave space between the value of temperature and the unit of degrees Celsius. Could you incorporate as well in the text an image of your raw material (Eucalyptus Clones specimens during testing for example?, since that would be much attractive to the readership. You could add a brief comment highlighting in the conclusions section the potential of utilizing these findings of yours in other areas as well (out of Vietnam).Author Response
Dear Reviewer 5,
We thank you for taking time to consider our work. We would like to address your concerns as in the attached file.
Author Response File: Author Response.docx
