3PG-MT-LSTM: A Hybrid Model under Biomass Compatibility Constraints for the Prediction of Long-Term Forest Growth to Support Sustainable Management

Round 1

Reviewer 1 Report

This article proposes a practical and effective hybrid modeling approach that combines physical constraints with simulation models to measure long-term changes in forest production.

The article should be revised with the following corrections:

1. Line 45: Please check the spelling of 'Introduction'.

2. In the introduction part, while it mentions that thinning is a common forestry management practice that improves the light and soil microenvironment and affects plant growth, it would be beneficial to elaborate on the specific benefits or outcomes of thinning.

3. How does thinning impact forest structure, ecological quality, and service functions?

4. What are the potential ecological and economic implications?

5. Line 145: Consider rephrasing the sentence "The growth rate of Norway spruce is at its peak between 20 and 90 years" to clarify whether it refers to the age of the trees or the forest stand.

6. In section 2.2, "The hybrid modeling approach":

   a. Consider providing a brief explanation of why the 3-PG model was chosen for biomass estimation. b. Clarify the specific data distribution and stand age information used for localizing the model in stages.

7. In section 2.2.3, "Loss function":

   Clarify the meaning of the variables Stem_pred, Root_pred, Leaf_pred, Aboveground_pred, and Total_pred in the loss function equation.

8. In line 293, "2 LSTM layers" should be "two LSTM layers".

 

Additionally, please check the following:

a. In line 240, "time range" should be "temporal range". b. In line 306, "loss function penalty values" can be rephrased as "penalty values in the loss functions". c. In line 369, please check "plants" and replace it with "trees".

Author Response

Dear reviewer:

The co-authors and I would like to thank you for the time and effort spent in reviewing the manuscript entitled “3PG-MT-LSTM: A hybrid model under biomass compatibility constraints for long-term forest growth prediction to support sustainable management” (Manuscript ID: forests-2499315). We have revised the whole manuscript according to your kind advices and detailed suggestions. The yellow part that has been revised according to your comments. The green part are other revisions.

 

Yours sincerely,

Jushuang Qin

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript entitled “3PG-MT-LSTM: A hybrid model under biomass compatibility constraints for long-term forest growth prediction to support sustainable management” reflects the development of applied research, the topic is interesting. However, the methods are not fully described, and results and discussion need to be improved. Thus, major changes are recommended.

 

Comments

1) Line 61 – the model refers to MAESTRA or TRIPLEX

2) Figure 1 – please include acronyms meaning

3) Lines 175 – please include a short summary of the method of Trotsiuk, to enable a better understanding of the method

4) Lines 178-180 – how was biomass estimated

5) Equations 2 to 6 – please include in the text the meaning of the variables

6) Line 208 – provide name prior to acronym

7)Line 223 – please describe shortly the scenarios

8) Lines 224-225 – the thinning method is missing. It is of primordial importance that the authors identify clearly the thinning method as well as if it was used only one thinning method or several. The interpretation of the results cannot be done without knowing the thinning method.

9) Line 225 – thinning intensity was 10%, 20% and 30% of what? Number of trees? Basal area? Volume? Or other variable?

10) Results section – it is not possible to fully analyse the results as thinning method is missing

11) Lines 234-235 – these methods are not in the methods section

12) Line 234 – reference of the software used (R program) should be added

13) Lines 293-296 - these methods are not in the methods section

14) Figure 6 – is difficult to read as graphics are too small

15) Line 349 – what do the author mean by thinning technique?

16) Line357 – what do the authors mean by “other thinning methods? thinning method was not defined

17) Lines 362-364 – please clarify text

18) Lines 399-401 – please clarify text

19) Lines404-405 – what do the authors mean by “When the canopy structure of the forest stand is reasonable”? please clarify text

20) Lines 477 – “Different tending and thinning techniques had a substantial impact on stand growth in addition to climate change”. Not possible to follow as thinning method was not defined

21) Line 480 – cultivation or production?

22) Line 487 – trimming branches or pruning?

23) Lines 487-497 – please revise English

24) Discussion – check for contradictions between results and discussion

Moderate editing of English language required

Author Response

Dear reviewer:

The co-authors and I would like to thank you for the time and effort spent in reviewing the manuscript entitled “3PG-MT-LSTM: A hybrid model under biomass compatibility constraints for long-term forest growth prediction to support sustainable management” (Manuscript ID: forests-2499315). We have revised the whole manuscript according to your kind advices and detailed suggestions. The green part that has been revised according to your comments. The yellow part are other revisions.

 

Yours sincerely,

Jushuang Qin

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The manuscript has improved in its second version. However, there is confusion between thinning method, intensity, and frequency. It is considered that without including in the text the thinning methods and the variable used for thinning intensity it is not possible to accept the manuscript in the present form. In the file response to reviewer 2 some explanations are given however they are not included in the revised version of the manuscript. Also, what is the meaning of Y, L, M, H, and T in table 1?

 

Comments

1) Line 64 – “The model exhibits” Which model? MAESTRA? TRIPLEX?

2) Line 261 - thinning methods are missing. The authors refer only to thinning intensity but not thinning method. Thinning method in the text or else the analysis of the results is not possible. Was the thinning method: thinning from above? Thinning from below? mechanical thinning? selective thinning? Moreover, the authors should specify of only one method was used or inversely several thinning methods.

3) Line 262-263 – thinning intensity was 10%, 20%, and 30% of what? In the response to reviewer 2, it is clear that the number of trees was used. Yet it is not in the text.

4) Line 279 - reference of the software used (R program) should be added

5) The former thinning technique should be replaced by the thinning regime. Thinning regime is the technical term that includes thinning method, intensity, and frequency.

6) Former “other thinning methods” as far as I understand are related to thinning intensity. Thus, thinning intensity should be used. Again, it is not clear if the thinning method is the same, so maybe thinning regime would be better suited.

7) Lines 519-520 – what about the thinning method?

Moderate editing of English language required

Author Response

Dear reviewer:

The co-authors and I would like to thank you for the time and effort spent in reviewing the manuscript entitled “3PG-MT-LSTM: A hybrid model under biomass compatibility constraints for long-term forest growth prediction to support sustainable management” (Manuscript ID: forests-2499315). We appreciate your detailed and professional suggestions. According to your comments, we have carefully amended the manuscript and answered the questions point by point. The blue part that has been revised according to your comments.

 

Yours sincerely,

Jushuang Qin

Author Response File: Author Response.docx