Beta Diversity Is Better—Microhabitat Diversity and Multiplet Diversity Offer Novel Insights into Plant Coexistence in Grassland Restoration

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

 This interesting methodological article deserves to be published. It raises important issues related to the restoration of grassland communities. As how Authors explained in the introduction “Restoration projects require long-term data collection and most projects which conduct monitoring prefer using simple sampling designs with few easily measurable attributes”. Most frequently alpha and gamma diversity are used. However, the Authors stated that beta diversity has great potential to reveal mechanisms behind community-level changes in succession.  They tested the behaviour and applicability of the chosen beta diversity measures (Microhabitat diversity; Multiplet diversity) taking into account a long-term dataset (9 years) from an active and passive grassland restoration project in Hungary. They found that microhabitat Diversity and Multiplet Diversity reflected well the expected differences between old fields recovering by active and passive restorations. Moreover, these beta diversity indices revealed that spontaneous self-organization was active in both sites. After 15 years, the structural complexity of sown grassland increased and the differences between sown and spontaneous grasslands started to disappear.

Below, I have included some suggestions.

I would reword the title of the article to make it more informative

Introduction

Line 141-148

It would be better to rephrase the text to underlie hypotheses and aims of the studies

We formulated the following hypotheses ….

We wanted to check if ....

The aim of studies was….

Results

I would divide the results into smaller subsections relating to the hypotheses or questions posed at the beginning of the paper

Line 280 – 281 – the first sentence is not necessary here.

I suggest dividing Results into subchapters referring to hypotheses and aims of the article

Line 354 – missing space

Line 443 – probably it should be Crepis rhoeadifolia

Line 447 – brackets not in italics

Line 478- 486 This text is a replication of a text given above

Line 490 missing space after grasslands

Line 504 – missing space after 15

Line 533 negative effect on what …

Fig. 2. C According to me it is too small and may not be readable

Latin names of plants should be written in italics (check also supplementary material

Comments for author File: Comments.pdf

Author Response

Detailed response to Referees:

 

Referee 1.

 

 This interesting methodological article deserves to be published. It raises important issues related to the restoration of grassland communities. As how Authors explained in the introduction “Restoration projects require long-term data collection and most projects which conduct monitoring prefer using simple sampling designs with few easily measurable attributes”. Most frequently alpha and gamma diversity are used. However, the Authors stated that beta diversity has great potential to reveal mechanisms behind community-level changes in succession.  They tested the behaviour and applicability of the chosen beta diversity measures (Microhabitat diversity; Multiplet diversity) taking into account a long-term dataset (9 years) from an active and passive grassland restoration project in Hungary. They found that microhabitat Diversity and Multiplet Diversity reflected well the expected differences between old fields recovering by active and passive restorations. Moreover, these beta diversity indices revealed that spontaneous self-organization was active in both sites. After 15 years, the structural complexity of sown grassland increased and the differences between sown and spontaneous grasslands started to disappear.

 

Response: Thank you for your detailed evaluation and for constructive comments. We respond point to point to your comments below. We also added here your comments written in the manuscript file.

 

Below, I have included some suggestions.

 

1, I would reword the title of the article to make it more informative

 

Response: Thank you for this important suggestion. We changed the title to more informative version as you suggested. The new title is: “Beta diversity is better – Microhabitat Diversity and Multiplet Diversity offer novel insights into plant coexistence during grassland restoration”

 

 

 

2, Introduction

    Line 141-148

   It would be better to rephrase the text to underlie hypotheses and aims of the studies

   We formulated the following hypotheses ….

   We wanted to check if ....

   The aim of studies was….

 

Response: We agree and rephrased the related text with explicit aims, questions and hypotheses. The related new text:

The aim of the study was to test the behavior and applicability of the proposed beta diversity metrics with long-term data from a restoration project in Hungary [48]. The used data represent active and passive restorations. In active restoration, the native dominant grass species of the reference community was sown in high density at the beginning of succession together with other subordinate target species. To study passive restoration we chose a spontaneously recovering site adjacent to species-rich, pristine grassland. We sampled the vegetation annually and followed the development of these sites over nine years (from ages 7 years to 15 years). We used three different sampling designs and estimated different alpha and beta diversity metrics.

We addressed three main questions:

1, How do stand-scale diversity patterns and species composition change during secondary succession in active and passive restoration? We hypothesize that the sown grassland will have higher alpha and gamma diversity with little changes over time during the study period. In contrast, steady increase of alpha and similar increase of gamma diversity are expected during spontaneous recovery.

2, How does the beta diversity of microhabitats formed by the dominant species change over time? We hypothesize that the sown grassland will have lower beta diversity at the beginning. However, we expect the difference between the actively and passively recovering grasslands to decrease in succession.

3, Do the fine-scale richness of subordinate species and the related Multiplet Diversity increase in succession? Will there be a difference between active and passive forms of recovery in this respect? We hypothesize larger Multiplet Diversity during spontaneous recovery and the dominance of low diversity microsites in the sown grassland. In both, we were interested in understanding how dominant species affect the accumulation of the target subordinate species.

In this paper, we compared the effectiveness of different sampling methods, and aim to highlight the novel insights and additional details provided by the proposed metrics of Microhabitat Diversity and Multiplet Diversity.

(Note: we refer always the line numbers from the original manuscript as you referred. Since then - due to revision of the manuscript – these parts appear with different line numbers.)

 

3, Materials and Methods in L  156,  You asked details about the definition of dominant species.

 

Response: This information was already available in the original manuscript between L 198 and L 209, in section 2.3. We described explicitely how dominant species were defined using 40% abundance threshold. Please,  refer also to Figure S3 and Table S1 for additional information.

 

4, Results

I would divide the results into smaller subsections relating to the hypotheses or questions posed at the beginning of the paper

 

Response: Thank you for this important suggestion. We made three subsections:

3.1. Stand-scale trends in succession revealed by different sampling methods

3.2. Within-stand variability of species richness and Microhabitat Diversity

3.3. Fine-scale patterns and coexistence relationships of subordinate species

These subsections structured according to the main questions in Introduction and we hope that these subsections will help to follow the information in the Results section.

 

5, Line 280 – 281 – the first sentence is not necessary here.

 

Response: deleted

 

6, I suggest dividing Results into subchapters referring to hypotheses and aims of the article

 

Response: done, please see our response above

 

7, Line 354 – missing space

 

            Response:  corrected

 

8, Line 443 – probably it should be Crepis rhoeadifolia

 

Response: Thank you, it was corrected to Crepis rhoeadifolia

 

8, Line 447 – brackets not in italics

 

Response: fixed

 

9, Line 478- 486 This text is a replication of a text given above

 

Response: Thank you, we deleted the redundant text

 

10, Line 490 missing space after grasslands

 

            Response:  corrected

 

11, Line 504 – missing space after 15

 

            Response:  corrected

 

12, Line 533 negative effect on what …

 

            Response:  Thank you, we added “on diversity”

 

13, Fig. 2. C According to me it is too small and may not be readable

 

Response: Thank you for this important suggestion. We made a new version of this figure using larger letter sizes. We prefer keeping this information with the  detailed example of calculations.

We introduced simple diversity indices and wanted to demonstrate the simplicity of calculations.

 

14, Latin names of plants should be written in italics (check also supplementary material

 

Response:  Thank you. We carefully revised the whole manuscript following the journal instructions about these details.

 

 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The restoration is one of the most important tools targeted to biodiversity conservation. I red this paper twice and I can say that it is not only very interesting but also a very practically approach. Based on 15 years time span the study of the dynamics of grassland vegetation in two areas of Hungary the authors succeed to present a clear perspective using two beta diversity indices. The method is very thorough presented and the chapter of "Discussions" is solid, well grounded, really impressive. Finally, I think that this paper may offer for everybody interested/implied in biodiversity conservation a strong tool for action. 

Author Response

Detailed response to Referees:

 

Referee 2.

 

The restoration is one of the most important tools targeted to biodiversity conservation. I red this paper twice and I can say that it is not only very interesting but also a very practically approach. Based on 15 years time span the study of the dynamics of grassland vegetation in two areas of Hungary the authors succeed to present a clear perspective using two beta diversity indices. The method is very thorough presented and the chapter of "Discussions" is solid, well grounded, really impressive. Finally, I think that this paper may offer for everybody interested/implied in biodiversity conservation a strong tool for action. 

 

Response: Thank you very much for your careful read and positive evaluations. We thank your points about our approach and we hope that these simple diversity indices we introduced here will be useful and widely applied in the restoration practice.

Author Response File: Author Response.pdf