Soil Biodiversity Integrates Solutions for a Sustainable Future

Round 1

Reviewer 1 Report

The subject of the manuscript is consistent with the scope of the Journal. The present paper is prepared in the usual manner for review manuscript, both the division into chapters, the selection of references. The results are correctly described. The conclusion corresponds with the work's content. I believe that it can contribute as a significant reference to the potential readers. The quoted literature is sufficient. The manuscript is well written, interestingly interpreted and should be disseminated.

Please, be sure that all the references are included in the reference list and vice versa with matching spellings and dates.

Author Response

Thank you for reviewing our work. We have double-checked all references and made minor adjustments to formatting and spelling as necessary.

Reviewer 2 Report

This is a review of soil biota, their role supporting ecosystem services, threats to soil biota, and ways to protect soils. I think there is a great wealth of information on the different ways in which soil organisms support the SDGs and Aichi Targets. My main issue with this paper is that biodiversity, to the extent that it's defined in this paper (L101) seems only to living communities, and not the actual diversity of those communities.There are some places where the extent of diversity is addressed implicitly (L110-113, mixed farming practices, the paper cited at L208), but much of the paper focuses on the ecosystem services provided by soil biota in general rather than how diversity of those organisms influences their functions (this is more what I was expecting). I think this is fine, but the authors may want to use a word like organisms or biota instead of biodiversity, which to me specifically indicates the extent of diversity. Although it is obvious that healthy biota are usually diverse biota, I think if the authors want to keep the term biodiversity they need to be clearer about the way that they use it in the text. 

Minor Comments:

Figure 2: "Specific SDGs are listed" <- but I don't see them, where are they?

There are a few places where I felt citations were needed: L123 "diverse soil communities are beneficial for human health", L167 (citation instead of Fig.2), L196-199, L413 "green spaces provide most biodiv"

L312-314: Can you simplify this sentence? It was a little hard to follow as written.

L331, L335: These two sentences are repetitive, I suggest combining them into one.

L88, L471: I'm not sure what the editorial board's philosophy is on this, but some consider statements like "more must be done" and "need to act now" to be subjective recommendations which can be read as biased.

Author Response

Thank you for reviewing our manuscript and making suggestions to strengthen it. Our responses appear in italics beneath your original comments.

This is a review of soil biota, their role supporting ecosystem services, threats to soil biota, and ways to protect soils. I think there is a great wealth of information on the different ways in which soil organisms support the SDGs and Aichi Targets. My main issue with this paper is that biodiversity, to the extent that it's defined in this paper (L101) seems only to living communities, and not the actual diversity of those communities.There are some places where the extent of diversity is addressed implicitly (L110-113, mixed farming practices, the paper cited at L208), but much of the paper focuses on the ecosystem services provided by soil biota in general rather than how diversity of those organisms influences their functions (this is more what I was expecting). I think this is fine, but the authors may want to use a word like organisms or biota instead of biodiversity, which to me specifically indicates the extent of diversity. Although it is obvious that healthy biota are usually diverse biota, I think if the authors want to keep the term biodiversity they need to be clearer about the way that they use it in the text. 

We have added some text to clarify our working definition of soil biodiversity in the manuscript:

Lines 53-54: “soil biodiversity - the diversity of life in soil which drives ecosystems, sustains life aboveground, and maintains healthy landscapes”

Which includes diversity, both across trophic levels and communities as well as within populations (genetic diversity).

We have changed biodiversity to biota in some places (e.g. lines 17, 21, 89, 242, 271, 309). Additional text has been added to acknowledge broader definitions of biodiversity:

Line 56-59: “Soil-dwelling organisms, including bacteria, fungi, nematodes, earthworms, moles and even plant roots, contribute the majority of living biomass on Earth [5], and represent more than 25% of all described species [6,7], not to mention the genetic diversity represented within these species.”

Lines 94-97: “For example, the majority of soil biodiversity research examines diversity at a community level, across species and trophic levels; however, diversity within species is a critical component of biodiversity which has all but ignored in soil habitats.”

Line 462-463: “Understanding and appreciating soil biodiversity within taxa is a major knowledge gap.”

Line 466-467: “Furthermore, lagging understanding genetic diversity within soil biota, both fauna and microbial could slow discovery of pharmaceuticals [22,29] as well as capacity for soil communities to respond to changing climate.”

Minor Comments:

Figure 2: "Specific SDGs are listed" <- but I don't see them, where are they?

Thank you for catching this, the text in the caption referred to an earlier version of this figure. It has been deleted.

There are a few places where I felt citations were needed: L123 "diverse soil communities are beneficial for human health", L167 (citation instead of Fig.2), L196-199, L413 "green spaces provide most biodiv"

We have added citations to these statements.

L312-314: Can you simplify this sentence? It was a little hard to follow as written.

We modified the sentence to read: “For example, using prescribed fire to reduce and prevent woody plant or invasive species encroachment in grasslands benefits soil-dwelling insects and aboveground organisms that rely on open grassland habitat [99]. Timing and intensity of fire can be modified to protect abundance and diversity of soil-dwelling insects.”

L331, L335: These two sentences are repetitive, I suggest combining them into one.

The sentence in line 331 refers to soil fauna, and the sentence in line 335 refers to microbial communities. We wrote these as separate sentences to distinguish studies focused on these two components of soil communities. We have elected to keep them as separate sentences and made some minor edits to clarify the distinction between the sentences. The section now reads:

“Soil fauna shift in community composition with time since restoration in North American tallgrass prairie [101–103], Costa Rican forests [104], and Australian mines [105], although in most cases, restored communities did not resemble communities in native reference ecosystems during the course of the study. Restoration practices in temperate woodlands and savannas increased collembola abundance and decreased non-native isopod habitat compared with no management [106]. Similarly, microbial communities show strong recovery trajectories with restoration in grasslands [107,108], wetlands [109], and forest [110], although they often fail to resemble native reference ecosystems.”

L88, L471: I'm not sure what the editorial board's philosophy is on this, but some consider statements like "more must be done" and "need to act now" to be subjective recommendations which can be read as biased.

A goal of our paper is to inspire action, supported by the research results synthesized in the manuscript, to protect and embrace soil biodiversity. As scientists who highly value objectivity, we recognize this can be uncomfortable and we respect the right of readers of Sustainability to reach their own conclusions. In this situation, as concerns have not been raised by the managing editor nor the other two reviewers, we would prefer to leave these two phrases as is.

Reviewer 3 Report

The article is top notch. I suggest that accept it with no revisions. 

Author Response

Thank you for reviewing our manuscript.

Round 2

Reviewer 2 Report

Thanks for taking the time to address all my comments. The authors further defined their use of the term biodiversity and clarified between biota and biodiversity where needed. They also clarified other points of confusion I had and addressed other minor comments to my satisfaction. I think this is a very well written and useful review and I support it's publication.