An Immense Knowledge Gap Relative to Regulated Logging Impacts in Tropical Forests

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This work provides insight into what additional information should be included in the work of other scientists studying forest management, such as the cycle of selective logging repetitions and the intensity of the treatment analyzed by the authors.

The work is methodically well-structured and well-organized, with explanatory figures.

It is not fully explained what the authors mean by the terms used in the article. Clear and understandable definitions or standardization of the terms used in the article are needed:

1. selective logging
2. regulated logging
3. selective "low-impact" logging
4. industrial-scale regulated logging

The authors seem to be somehow linking selective logging with forest area reduction, which would be a serious mistake. These two issues should be clearly distinguished and not conflated. Forest management (in any form consistent with forestry knowledge) has nothing to do with excluding forest areas and reclassifying them for other purposes. The bias of such an approach would be striking in the reviewed article and would undermine its scientific value. In other words, invalid conclusions would be drawn based on the results of metadata analysis. 376-389

The title of the paper is catchy, but there's little mention of the "hidden costs" mentioned in the title. The title, however, certainly lacks any information about the benefits of conducting reliable, true, and honest forest management, as precisely outlined in the Discussion. Such unequal treatment of forest use seems unjustified. 390-398.

So, perhaps – keeping the science serious - the title should be: The hidden costs and revealed profits of selective logging: what can be learnt from metadata analysis...?

Remove all „sees’ in citations (see Sist et al., 2021; Tritsch et al., 2020). 72

(see Chan, 2017) with public concessions achiev- 80

(see also Azevedo-Ramos et al.,) 84

 

Repetition:

Our database is available on GitHub (github.com/miralaba/logging scientiometrics). 153

The information extracted from each document, and the 212 metadata with the appropriate category description, is available on GitHub 213 (github.com/miralaba/logging scientiometrics). 214

 

Author Response

Revisor 1

1. It is not fully explained what the authors mean by the terms used in the article. Clear and understandable definitions or standardization of the terms used in the article are needed:

1. selective logging
2. regulated logging
3. selective "low-impact" logging
4. industrial-scale regulated logging

R: Done.

 

1. The authors seem to be somehow linking selective logging with forest area reduction, which would be a serious mistake. These two issues should be clearly distinguished and not conflated. Forest management (in any form consistent with forestry knowledge) has nothing to do with excluding forest areas and reclassifying them for other purposes. The bias of such an approach would be striking in the reviewed article and would undermine its scientific value. In other words, invalid conclusions would be drawn based on the results of metadata analysis. 376-389

R: Now the text is clearer (lines 374-384) "We refer to expressive habitat loss and forest degradation promoted by other land uses rather than regulated logging (e.g., crop/cattle production), embedding logging forests into degraded landscapes and then turning these forests much more vulnerable to edge-effects, wildfires and defaunation for instance. In synthesis, regulated logging via presumable sustainable under approaches operates and continues to expand a high level of uncertainty, which emerges from the current knowledge gaps [31,32,43,44,100] plus those induced by changes in the ecological context logging are expected to occur. As old-growth forests become increasingly embedded within human-modified landscapes, long-term assessments of logging sustainability become more uncertain, particularly under ecological conditions that differ from those examined by the current literature [97,101].”.

 

398. The title of the paper is catchy, but there's little mention of the "hidden costs" mentioned in the title. The title, however, certainly lacks any information about the benefits of conducting reliable, true, and honest forest management, as precisely outlined in the Discussion. Such unequal treatment of forest use seems unjustified. 390-398.

So, perhaps – keeping the science serious - the title should be: The hidden costs and revealed profits of selective logging: what can be learnt from metadata analysis...?

R: Thank you very much for the suggestion. We changed the title to "An immense knowledge gap relative to regulated logging impacts in tropical forests".

 

1. Remove all „sees’ in citations (see Sist et al., 2021; Tritsch et al., 2020). 72

(see Chan, 2017) with public concessions achiev- 80

(see also Azevedo-Ramos et al.,) 84

R: Done.

 

 

Reviewer 2 Report

Comments and Suggestions for Authors

The paper does not contain gross violations of citation ethics (such as plagiarism or fictitious references). However, there is a systematic problem of selective citation: the authors refer to studies that support the "sustainability" of logging, but do not adequately represent the literature that calls this sustainability into question. This contradicts their stated aim to "question the empirical support for the alleged sustainability" and undermines confidence in the objectivity of the review.

The article fully aligns with the scope of journals focused on forest ecology and forest resource management. The research question is clearly formulated: the authors aim to identify spatial, temporal, and thematic gaps in the literature on selective logging in the tropics. The research question itself is not novel, but the originality of the work lies in the fact that the authors, for the first time on such a scale, analyze not only thematic coverage but also how often researchers control for key variables: logging intensity, number of cycles, and time since logging. This is a truly important aspect that has not been systematically assessed before.

The authors convincingly demonstrate that nearly half of the studies (47%) do not report logging intensity — a critical shortcoming that makes it impossible to compare results. They find that most studies focus on the first logging cycle in old-growth forests, whereas repeated logging cycles (which occur in practice) remain largely unstudied. It is shown that even when key variables are controlled, the number of studies on most topics does not exceed five — an important empirical argument against claims of "proven sustainability."

At the same time, the following shortcomings can be noted:

The authors state that they intend to question the empirical basis of alleged sustainability. However, in the text (especially in the Introduction and Discussion), they cite studies that support sustainability, but do not cite, or cite insufficiently, studies demonstrating negative long-term consequences even under "sustainable" logging regimes. This creates a false impression of balance.

The Introduction and Discussion sections need to be revised by adding explicit references to studies showing negative long-term consequences. Only then will the conclusion about "uncertainty" and "insufficient evidence" become truly justified. In its current version, the review creates an illusion of greater support for sustainability than actually exists in the literature, which contradicts the stated aim.

The article is a descriptive review, but even in this format, several testable hypotheses could have been formulated. The findings regarding geographical (Brazil, Malaysia) and taxonomic (birds, mammals, trees) biases in the research are not new — they have been described repeatedly before. Furthermore, at least a comparative analysis across regions could have been conducted.

The authors used only one source (Scopus). Although Scopus is a major database, the exclusion of Web of Science, Google Scholar, and regional databases (e.g., SciELO for Latin America) may have exacerbated geographical bias. This is a serious methodological limitation.

Statistical methods are practically absent. The authors report only frequencies and percentages. There is no testing for significance of differences between regions or time periods. No analysis of temporal trends (e.g., Poisson regression for the number of publications per year) is provided. The review lacks formal comparison between regions or time periods; the authors simply list numbers. For example, they state that in Africa, 12 topics have 1–5 studies, whereas in the Neotropics, 9 topics fall into this range. But is this difference statistically significant?

Author Response

Revisor 2

1. However, there is a systematic problem of selective citation: the authors refer to studies that support the "sustainability" of logging, but do not adequately represent the literature that calls this sustainability into question. This contradicts their stated aim to "question the empirical support for the alleged sustainability" and undermines confidence in the objectivity of the review.

R: Thank you very much for your important observation. Now, some references that question the sustainability of the activity have been clearly included.

 

1. At the same time, the following shortcomings can be noted:

The authors state that they intend to question the empirical basis of alleged sustainability. However, in the text (especially in the Introduction and Discussion), they cite studies that support sustainability, but do not cite, or cite insufficiently, studies demonstrating negative long-term consequences even under "sustainable" logging regimes. This creates a false impression of balance.

R: Same answer as the previous question.

 

1. The Introduction and Discussion sections need to be revised by adding explicit references to studies showing negative long-term consequences. Only then will the conclusion about "uncertainty" and "insufficient evidence" become truly justified. In its current version, the review creates an illusion of greater support for sustainability than actually exists in the literature, which contradicts the stated aim.

R: Done.

 

1. The authors used only one source (Scopus). Although Scopus is a major database, the exclusion of Web of Science, Google Scholar, and regional databases (e.g., SciELO for Latin America) may have exacerbated geographical bias. This is a serious methodological limitation.

R: We acknowledge the limitation, and the text already has a section making that very clear. “2.3. Potential limitations and caveats. Our review was based on a systematic and validated procedure, while our search was limited to the Scopus platform. However, Scopus' extensive coverage of nearly 28,000 active titles, stands as a widely recognized and comprehensive repository, minimizing the potential impact on the robustness of our review's conclusions. By restricting search to papers available via public platforms, we assumed that they provide a good proxy to the current accumulated knowledge on the impacts by selective logging in tropical forests.”.

 

1. Statistical methods are practically absent. The authors report only frequencies and percentages. There is no testing for significance of differences between regions or time periods. No analysis of temporal trends (e.g., Poisson regression for the number of publications per year) is provided. The review lacks formal comparison between regions or time periods; the authors simply list numbers. For example, they state that in Africa, 12 topics have 1–5 studies, whereas in the Neotropics, 9 topics fall into this range. But is this difference statistically significant?

R: We acknowledge the absence of statistical methods, but our goal has always been a descriptive, not a comparative, diagnosis. Given the results we found, the lack of information/data would even make some analyses impossible.