The Influence of Tilia tomentosa Moench on Plant Species Diversity and Composition in Mesophilic Forests of Western Romania–A Potential Tree Species for Warming Forests in Central Europe?
, Veronika Öder 3, Adrian Indreica 4, Erwin Bergmeier 3, Christoph Leuschner 5 and Helge Walentowski 1,*
Round 1
Reviewer 1 Report
This manuscript investigates the influence of silver lime on plant species diversity and composition in Romania. The findings are interesting and can attract international readers. However, the manuscript is too long and verbs such that the same concepts/descriptions are repeated with different writings. I strongly recommend streamlining the manuscript to provide the most important results and related discussion. I think the number of citations for some general descriptions is too high (e.g., lines 49-67, and also several other parts). The authors can cite one or at most two references for such descriptions. Going through the manuscript, I found several grammar and syntax errors that need the authors' attention. Finally, finish your Abstract section with a clear conclusion/ implication. I can recommend the publication of this manuscript, when these points are adequately addressed.
Author Response
General response: Please note that the given line numbers in our responses refer to the untracked version of our revised manuscript.
Comments and Suggestions for Authors
This manuscript investigates the influence of silver lime on plant species diversity and composition in Romania. The findings are interesting and can attract international readers.
Response: Thank you very much for the positive evaluation of our manuscript.
However, the manuscript is too long and verbs such that the same concepts/descriptions are repeated with different writings. I strongly recommend streamlining the manuscript to provide the most important results and related discussion.
Response: We have shortened the manuscript in several places mainly by removing repetitions (please compare the tracked version of our revision with the original version) and are more straight on the main findings of our study (e. g. see lines 438-430 and 602-607).
I think the number of citations for some general descriptions is too high (e.g., lines 49-67, and also several other parts). The authors can cite one or at most two references for such descriptions.
Response: Even though we added some references in response to reviewer 2, we have reduced the number of citations from 80 to 72. Particularly in the lines 48 to 64, when characteristics of Tilia tomentosa are described, we have reduced the number of references.
Going through the manuscript, I found several grammar and syntax errors that need the authors' attention.
Response: We are sorry for the editing and also for the formatting errors that occurred in the first version. We have carefully read through the manuscript again and hope to have eliminated the errors.
Finally, finish your Abstract section with a clear conclusion/ implication.
Response: We have changed the final sentences of the abstract and now give a clear conclusion (see lines 30-32) which reads as follows: “Thus, silver lime may have the potential as an admixed tree species forming a transitory meso-thermophilous habitat in the future. At the same time, silver lime may be limited under increasing drought frequency.”
I can recommend the publication of this manuscript, when these points are adequately addressed.
Response: Thank you very much.
Reviewer 2 Report
Generally, the manuscript is very well written and fits well the scope of Sustainability journal. Authors of this interesting study opened a relatively new idea related to changes in (not only) tree diversity in European forests under global climate change. By results of this study, Silver lime seems to be a potential future tree species with more important role in temperate mesophilic forests despite of fact it is non-native tree species. This issue (including using of non-native trees in future forest management) is in the focus of current discussions of conservationists and both forest researchers and forest-management decision makers worldwide. Similar topics are discussed about potential applying of oak species from Balcan to temperate lowland Central-European forests. Also, there are many doubts related to sustainability of the future forest management practice based on new non-native (introduced) species. Yeas, many (maybe most) tree species will change geographical areas under climate changes, but discussion is not still concluded with clear answers for such important questions as “Is wider using of non-native species – determinants of ecosystems - acceptable in the frame of biodiversity conservation?” etc. So, this study - if accepted for publication - can fits any important current knowledge-gaps in this topic. Especially Figure 3 is valuable in this context because clear shows differences in gamma diversity of forest types.
I have only some minor comments to the manuscript:
In the section Introduction, Authors should extend the scientific background to recent studies of tree-species predicted changes in Central-European temperate forests (e. g. study doi: 10.2478/jlecol-2018-0012).
Section Methods: If possible, can Authors add any detailed information about forest management history of study sites? How former coppice (line 134) influenced current ecological conditions of study sites? What current forest management is exactly applying in both study sites?
Authors should highlight in the section Discussion, which forest types (based on management types) are suitable for applying non-native tree species and where it is not probably generally accepted, such as in protected areas (see doi: 10.3897/natureconservation.22.12902). It should be more discussed in details by Authors of this manuscript.
I am not sure if Western Romania is a part of Central Europe (or better of South-Eastern Europe).
Author Response
General response: Please note that the given line numbers in our responses refer to the untracked version of our revised manuscript.
Comments and Suggestions for Authors
Generally, the manuscript is very well written and fits well the scope of Sustainability journal. Authors of this interesting study opened a relatively new idea related to changes in (not only) tree diversity in European forests under global climate change. By results of this study, Silver lime seems to be a potential future tree species with more important role in temperate mesophilic forests despite of fact it is non-native tree species. This issue (including using of non-native trees in future forest management) is in the focus of current discussions of conservationists and both forest researchers and forest-management decision makers worldwide. Similar topics are discussed about potential applying of oak species from Balcan to temperate lowland Central-European forests. Also, there are many doubts related to sustainability of the future forest management practice based on new non-native (introduced) species. Yeas, many (maybe most) tree species will change geographical areas under climate changes, but discussion is not still concluded with clear answers for such important questions as “Is wider using of non-native species – determinants of ecosystems - acceptable in the frame of biodiversity conservation?” etc. So, this study - if accepted for publication - can fits any important current knowledge-gaps in this topic. Especially Figure 3 is valuable in this context because clear shows differences in gamma diversity of forest types.
Response: Thank you very much for the positive evaluation of our manuscript and for seeing the potential of our study to contribute to ongoing discussions on the suitability of non-native tree species for Central Europe in the future.
I have only some minor comments to the manuscript:
In the section Introduction, Authors should extend the scientific background to recent studies of tree-species predicted changes in Central-European temperate forests (e. g. study doi: 10.2478/jlecol-2018-0012).
Response: We have rewritten the first sentences of the introduction and now mention aspects of potential range shifts and tree species being affected by higher rates of mortality due to climate change (see lines 38-39). We have added some additional references by Machar et al. 2018 [1] and Schuldt et al. 2020 [2]. In addition, Buras & Menzel 2019 [3] provide a recent projection of future tree species composition of Central Europe under the RCP scenarios. As reviewer 1 asked for cutting the number of citations in the introduction, we have not added more studies on this topic.
Section Methods: If possible, can Authors add any detailed information about forest management history of study sites? How former coppice (line 134) influenced current ecological conditions of study sites? What current forest management is exactly applying in both study sites?
Response: We provide detailed information on forest management in lines 127-146. Forests of the three different study areas all originate from natural regeneration (lines 139-140) and are generally managed under the same management regime (group selection management, see line 128) as high forests according to management plans. Before that, irregular cutting occurred as well as coppicing and wood pasture. There is, however, no detailed stand level information from before 1960. In forests dominated by silver lime coppicing was applied in former times, currently stands are also managed using group selection cuttings.
Study areas, however, differ in disturbance and management history as far as we have been able to reconstruct this. We have moved this section from the discussion to the methods section to provide this information earlier within the manuscript (see lines 140-146). We also refer to the publication of Öder et al. 2021 [36] published in Forest Ecology and Management. Authors investigated similar study sites and provided detailed information of forest management.
Authors should highlight in the section Discussion, which forest types (based on management types) are suitable for applying non-native tree species and where it is not probably generally accepted, such as in protected areas (see doi: 10.3897/natureconservation.22.12902). It should be more discussed in details by Authors of this manuscript.
Response: We have now added to the conclusion that the introduction of silver lime as a non-native species is unadvisable within areas left for natural development and in open oak forests to avoid potential adverse effects on the forest habitat (see lines 609-612). We also make sure that this tree species presumably cannot compensate for a potential loss of native oak species (lines 557-558).
I am not sure if Western Romania is a part of Central Europe (or better of South-Eastern Europe).
Response: We investigated western Romania as part of South-eastern Europe though in transition to Central Europe as an analogous climate region with climatic conditions expected in Central Europe within the next decades. In the methods section and conclusion, we now mention the edge position of western Romania for Central Europe (see lines 50-51 and 591-592).
