Extreme Winter Storms Have Variable Effects on the Population Dynamics of Canopy Dominant Species in an Old-Growth Subtropical Forest

Round 1

Reviewer 1 Report

Dear Authors,

Please find my comments and suggestions in the attached PDF. You could directly reply to my comments in the PDF during your revision.

Overall, I think this is a nice study and provide valuable insights into forest dynamics under extreme winter storms. But revisions are needed to improve the qa.

Comments for author File: Comments.pdf

Author Response

Please see detialed reponses in the PDF document

Author Response File: Author Response.pdf

Reviewer 2 Report

The topic of the manuscript " Extreme Winter Storms Have Variable Effects on the Population Dynamics of Canopy Dominant Species in an Old-Growth Subtropical Forest " is timely and fits within the scope of the Journal. However, I have highlighted weaknesses in the manuscript that need improvement. These are the description of the reults (Section 3) and especially the description of the results given in Section 3.3 and Figure 4. I provide detailed comments on these subsections below. 

Comments for author File: Comments.pdf

Author Response

Reviewer 2

Detailed comments:

3. Results

3.1 Changes of population characteristics of canopy dominant species

Line 176: From 2005 to 2010, the diameter structure remained basically stable (Fig. 2 a, c, e, g).

The sentence is not entirely true. There are places on Fig. 2e and 2g where there can be significant differences.

Response: Although there are some differences in the diameter structures of the two species represented in Figure 2e, g , the overall trend in the figure is consistent and the diameter structures are still relatively stable.

Line 177: The diameter structure of C. eyrei, S. superba and D. oldhamii showed bimodal distribution. The diameter structure of D. oldhamii does not have a bimodal distribution.

Response: Revised.

Lines 178-179: Individuals of C. eyrei and S. superba mainly peaked at 2cm and 30cm, while D. oldhamii showed multimodal distribution (Fig. 2 a, c, g). The statement "D. oldhamii showed multimodal distribution" contradicts the previous sentence.

Response: Thanks for point out this. This sentence changed to "The diameter structure of C. eyrei and S. superba showed bimodal distribution. Individuals of C. eyrei and S. superba mainly peaked at 2 cm and 30 cm (Fig. 2 a, c), while D. oldhamii showed multimodal distribution (Fig. 2 g)." in the revised manuscript.

Lines 180-183: The numbers of recruitments, upgrades and mortality of C. eyrei, S. superba, and D. oldhamii populations all decreased with the increase of diameter classes (Fig. 2 b, d, h), while P. massoniana showed no significant decreasing trend in any category (Fig. 2 f). The numbers of mortality (2b, 2d, 2f) is at the same level, in order to show a decrease you need to perform the appropriate statistical tests.

Response: We removed the description of mortality rate and revised this sentence. As for statistical tests, it hard to find a way to test whether the change is significant or not. We tried our best to describe the trend more carefully.

Lines 183-185: All the population change rates were negative (Table 2). The number of individuals in the small diameter class (DBH 1-1.4cm) decreased the most (Fig. 2 b, d, f, h). Fig. 2f does not show this.

Response: Although the overall variation in Figure 2f is small, the mortality rate in DBH1-1.4 cm is much greater than that in other diameter classes, we tried to make it more clear in the revised manuscript.

3.2. Differences in the distribution of dead trees in different habitats

Lines 195-196: The four dominant populations (C. eyrei, S. superba, P. massoniana and D. oldhamii ) were mainly distributed in low valleys and low ridges (Fig. 3 a, e, i, m).

Fig. 3a, C. eyrei, low ridge – is true;

Fig. 3e, S. superba, high ridge is not true;

Fig. 3i, P. massoniana, high ridge is not true;

Fig. 3m, D. oldhamii, low ridge – is true.

Response: Revised, we changed the description to "The four dominant populations (C. eyrei, S. superba, P. massoniana and D. oldhamii) were mainly distributed in low valleys and low ridges (Fig. 3 a, e, i, m). Specifically, S. superba and P. massoniana were relatively more distributed in high-altitude areas (Fig. 3 e, i).".

Lines 198-200: From low valleys to high ridges, the density of C. eyrei, S. superba and P. massoniana populations gradually increased (Fig. 3 b, f, j), and the death number and mortality rate of C. eyrei and S. superba populations gradually decreased (Fig. 3 c, d, g, h).

Fig. 3g chart does not show this.

Response: Thanks for the correction, here it is changed to "From low valleys to high ridges, the density of C. eyrei, S. superba and P. massoniana populations gradually increased (Fig. 3 b, f, j), the mortality rate of C. eyrei and S. superba populations gradually decreased (Fig. 3 d, h), the death number of C. eyrei population gradually decreased (Fig. 3 c), and the death number of S. superba population decreased and then increased (Fig. 3 g).".

Lines 202-204

The density of D. oldhamii population was higher in the low-altitude area, and from low valleys to high ridges, the death number and mor- tality rate of this population were gradually decreased (Fig. 3 n, o, p). Fig. 3p chart shows no gradual decline.

Response: Thanks for the correction, here it is changed to "The density of D. oldhamii population was higher in the low-altitude area, and from low valleys to high ridges, the death number and mortality rate were much greater at low-altitude areas than at high-altitude areas".

3.3. Spatial point pattern of dead trees across life stages

What is the point of section 3.3? How about removing this section?

Response: For section 3.3, we would like to show the spatial pattern of dead individuals which caused by the winter storm for the four dominate species. In the revised manuscript, we still keep this section, we think the section could provide spatial knowledge of the damage of the winter storm on the dominate species.  

The above comments call for improvements to the text in sections 4 and 5.

Response: Thanks for point out this. we revised sections 4 and 5 in the manuscript accordingly according to the comments mentioned above.

Author Response File: Author Response.pdf

Reviewer 3 Report

The paper entitled "Extreme winter storms have variable effects on the population dynamics of canopy dominant species in an old-growth subtropical forest" is topical, fits well with the Forests journal's scope, and provides valuable results about subtropical forest ecosystem dynamics after a severe winter storm. The article is well-organised, title and abstract are concisely written. English quality is acceptable; however, some typos are still present (comments below) despite native speaker proofreading. Generally, the research was consistently designed. The Introduction section could be improved. Original large datasets were comprehensively presented, analysed using adequate statistical methods, and discussed with relevant papers in the studied domain. The text should use the correct forest terminology (please see my comments below).

I have some comments and remarks below, which I would request authors to implement and consider in the manuscript body.

Ln. 46: Please consider replacing "soil" with "nutrient and water availability"

Ln. 49-50: Very propitious effect to enrich soil horizon by organic matter provide mainly pioneer tree species, such as birch, alder etc. Please, consider additional suitable references.

Ln. 57-64: This part seems more like the Material and Method section. Please, consider moving it there.

Ln. 67: "…interact directly with the external…" replace by "…interact directly through leaf area with the external…" Note: leaf area (green foliage) is the interstices between plants and the atmosphere where many physiological processes (photosynthetic uptake, respiration, transpiration etc.) are implemented.

Ln. 70: Please, consider rebuilding the sentence "Canopy-dominant species therefore reflect…" to "Therefore, canopy-dominant species reflect…"

Ln. 82: Change "Tree census" to ordinarily used "Tree inventory"

Ln. 83-89: In the title, old-growth stands are mentioned. However, please, also present the age range for the studied forest ecosystem.

Ln. 90 (Figure 1 on the left): Please, add the North and measuring scale to the map.

Ln. 90 (Figure 1 on the right): Please, add the legend representing the particular studied habitats as mentioned in the Ln. 106-107.

Ln. 117: Please, change the name of the subchapter "Importance value" to "Importance value of dominant tree species"

Ln. 138: Please, change the name of the subchapter "Division of diameter structure" to "Diameter structure classes"

Ln. 142: Please, add a histogram with DBH classes distribution at least for four main studied tree species.

Ln. 174 (Table 1): Please, check the caption of the second and third columns. Should it not be "Importance value (IV)" instead of "Important values" there?

Ln. 177: D. oldhamii did not show a bimodal distribution but multimodal (please, see Fig. 2g) and Ln. 179.

Ln. 186 (Table 2): Change "species" by "Species" and "recruitment rate" by "Recruitment rate"

Ln. 205 (Figure 3): Zoom up the chart legend (it is almost illegible) and move it to the upper right corner.

Ln. 205 (Figure 3): For better clarity, please add the C. eyrie above (a-d), S. superba above (e-h), P. manssoniana above (i-l), and D. oldhamii above (m-p) chart section.

Ln. 210-211. Please, remove the part "a, Low valley; b, Low ridge; c, Mid slope; d, High slope; e, High ridge.)." It is redundant because habitat types are evident from the chart legend.

Ln. 213-217: This paragraph is difficult to evaluate because of the very low legibility of Figure 4.

Ln. 218 (Figure 4): Zoom up the chart legend and move it to the upper right corner, and zoom up individuals' spatial point patterns.

Ln. 231-232: "…resulting in the population exhibiting a negative growth trend." It is valid only from the viewpoint of the basal area at the plot level. DBH trend increased (see Ln. 171-172 and Ln. 239-240) because competition among surviving trees decreased after the windstorm.

Ln. 249-250: As per my previous comment, D. oldhamii did not show a bimodal distribution but multimodal (please, see Fig. 2g) and Ln. 179.

Ln. 257-258: On the contrary, the large-diameter trees have a more extended leaf area, representing the snow interception area. Please, consider this fact in the discussion.

Ln. 263: Please, replace "…with low hardness" with "…with low strength"

Ln. 275: Please, consider the change from "…and mortality. Ge et al. found a similar result." to "and mortality as similarly found by Ge et al."

Ln. 289: Replace "light-loving species" with "light-demanding tree species"

Ln. 292: Please change "causing trees to fall or die" to "causing trees' breakage or die"

Ln. 296: Replace "…between the high-altitude area and low-altitude area…" with "…between the high- and low-altitude areas…"

Ln. 299: Replace "low altitude" with "low-altitude"

Ln. 306: Please, replace "…when the conspecific density is higher" with "…when the CNDD is higher"

 

Ln. 308: Replace "low altitude" with "low-altitude"

Author Response

Reviewer 3

The paper entitled "Extreme winter storms have variable effects on the population dynamics of canopy dominant species in an old-growth subtropical forest" is topical, fits well with the Forests journal's scope, and provides valuable results about subtropical forest ecosystem dynamics after a severe winter storm. The article is well-organised, title and abstract are concisely written. English quality is acceptable; however, some typos are still present (comments below) despite native speaker proofreading. Generally, the research was consistently designed. The Introduction section could be improved. Original large datasets were comprehensively presented, analysed using adequate statistical methods, and discussed with relevant papers in the studied domain. The text should use the correct forest terminology (please see my comments below).

Response: Thank you for your recognition of our study, and thanks for the detailed comments and suggestions which helped us to improve our manuscript greatly.

I have some comments and remarks below, which I would request authors to implement and consider in the manuscript body.

Ln. 46: Please consider replacing "soil" with "nutrient and water availability"

Response: Done.

Ln. 49-50: Very propitious effect to enrich soil horizon by organic matter provide mainly pioneer tree species, such as birch, alder etc. Please, consider additional suitable references.

Response: Revised.

Ln. 57-64: This part seems more like the Material and Method section. Please, consider moving it there.

Response: In the revised version, we moved this part to Material and Method section, as part of 2.1.

Ln. 67: "…interact directly with the external…" replace by "…interact directly through leaf area with the external…" Note: leaf area (green foliage) is the interstices between plants and the atmosphere where many physiological processes (photosynthetic uptake, respiration, transpiration etc.) are implemented.

Response: Thank you for your suggestion, Revised.

Ln. 70: Please, consider rebuilding the sentence "Canopy-dominant species therefore reflect…" to "Therefore, canopy-dominant species reflect…"

Response: Revised.

Ln. 82: Change "Tree census" to ordinarily used "Tree inventory"

Response: Revised.

Ln. 83-89: In the title, old-growth stands are mentioned. However, please, also present the age range for the studied forest ecosystem.

Response: Here we defined our forest plot as old-growth forest following the definition in previous studies such as Legendre et al. (2009) and Forestry Chorography in Kaihua County. This forest has not experienced natural or human disturbances since the 2020s (Editorial Group of Forestry Chorography in Kaihua County, 1988). Based on our dataset, the maximum diameter at breast height (DBH) in the forest is 95 centimeters. Although we lack the specific age of the forest, we can define this forest as old-growth forest based on the above evidence. We added the description in the Material and Method section in the revised version.

Legendre, P., Mi, X., Ren, H., Ma, K., Yu, M., Sun, I.-F. & He, F. Partitioning beta diversity in a subtropical broad-leaved forest of China. Ecology. 2009, 90, 663-674.

Editorial Group of Forestry Chorography in Kaihua County. Forestry Chorography in Kaihua County, Zhejiang People 's Publishing House: Hangzhou, China. 1988. (in Chinese)

Ln. 90 (Figure 1 on the left): Please, add the North and measuring scale to the map.

Response: added.

Ln. 90 (Figure 1 on the right): Please, add the legend representing the particular studied habitats as mentioned in the Ln. 106-107.

Response: In the revised version, we added a description of the habitats. More detailed information could be found in Chen et al. (2010).

Ln. 117: Please, change the name of the subchapter "Importance value" to "Importance value of dominant tree species"

Response: Revised.

Ln. 138: Please, change the name of the subchapter "Division of diameter structure" to "Diameter structure classes"

Response: Revised.

Ln. 142: Please, add a histogram with DBH classes distribution at least for four main studied tree species.

Response: In the revised version, we added DBH classes distribution histogram as supplementary materials.

Ln. 174 (Table 1): Please, check the caption of the second and third columns. Should it not be "Importance value (IV)" instead of "Important values" there?

Response: Revised.

Ln. 177: D. oldhamii did not show a bimodal distribution but multimodal (please, see Fig. 2g) and Ln. 179.

Response: We changed to “The diameter structure of C. eyrei and S. superba showed bimodal distribution. Individuals of C. eyrei and S. superba mainly peaked at 2cm and 30cm (Fig. 2 a, c), while D. oldhamii showed multimodal distribution (Fig. 2 a, c, g).”

Ln. 186 (Table 2): Change "species" by "Species" and "recruitment rate" by "Recruitment rate"

Response: Revised.

Ln. 205 (Figure 3): Zoom up the chart legend (it is almost illegible) and move it to the upper right corner.

Response: The legend has been enlarged and moved to the upper right corner.

Ln. 205 (Figure 3): For better clarity, please add the C. eyrie above (a-d), S. superba above (e-h), P. manssoniana above (i-l), and D. oldhamii above (m-p) chart section.

Response: Species information has been added to each panel map

Ln. 210-211. Please, remove the part "a, Low valley; b, Low ridge; c, Mid slope; d, High slope; e, High ridge.)." It is redundant because habitat types are evident from the chart legend.

Response: Done.

Ln. 213-217: This paragraph is difficult to evaluate because of the very low legibility of Figure 4.

Response: We revised this paragraph according Figure 4 to make it more legibility.

Ln. 218 (Figure 4): Zoom up the chart legend and move it to the upper right corner, and zoom up individuals' spatial point patterns.

Response: Done.

Ln. 231-232: "…resulting in the population exhibiting a negative growth trend." It is valid only from the viewpoint of the basal area at the plot level. DBH trend increased (see Ln. 171-172 and Ln. 239-240) because competition among surviving trees decreased after the windstorm.

Response: This conclusion is obtained from the population change rates in Table 2, which are negative for all four species. Although the DBH at the plot level increased, the number of individuals in the population and the basal area at plot level decreased. The increase in DBH at the plot level is mainly due to the creation of forest gaps after the winter storm and accelerated plant growth.

Ln. 249-250: As per my previous comment, D. oldhamii did not show a bimodal distribution but multimodal (please, see Fig. 2g) and Ln. 179.

Response: Revised. This sentence was changed to “We found that the diameter structure of the three evergreen broad-leaved species (C. eyrei, S. superba, and D. oldhamii) populations showed bimodal and multimodal distribution. This distribution indicates that the population has developed to more advanced stages, and the whole population is relatively stable.” (The multimodal distribution in the literature also represents population stability)

Ln. 257-258: On the contrary, the large-diameter trees have a more extended leaf area, representing the snow interception area. Please, consider this fact in the discussion.

Response: Thanks for the suggestion. We revised this part to “The large-diameter trees have a more extended leaf area, representing the snow interception area is larger. Small-diameter individuals do not have strong trunk support and are susceptible to mechanical damage caused by the pressure of snow and nearby large tree branches.”

Ln. 263: Please, replace "…with low hardness" with "…with low strength"

Response: Revised.

Ln. 275: Please, consider the change from "…and mortality. Ge et al. found a similar result." to "and mortality as similarly found by Ge et al."

Response: Revised.

Ln. 289: Replace "light-loving species" with "light-demanding tree species"

Response: Revised.

Ln. 292: Please change "causing trees to fall or die" to "causing trees' breakage or die"

Response: Revised.

Ln. 296: Replace "…between the high-altitude area and low-altitude area…" with "…between the high- and low-altitude areas…"

Response: Revised.

Ln. 299: Replace "low altitude" with "low-altitude"

Response: Revised.

Ln. 306: Please, replace "…when the conspecific density is higher" with "…when the CNDD is higher"

 Response: Revised.

Ln. 308: Replace "low altitude" with "low-altitude"

Response: Revised.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The manuscript has been improved, but I strongly suggest another round of thorough English checking!

I can easily spot some grammar issues, such as, in Line 175, change stand for to 'stands for'. 

Reviewer 2 Report

My comments have been taken into account in the revised version.

I consider the form of the article revised and acceptable.

Reviewer 3 Report

After thorough re-reading, I recommend the paper mentioned above for publishing in the Forests journal.