The Search for the Meaning of Soil Health: Lessons from Human Health and Ecosystem Health
Round 1
Reviewer 1 Report
The authors raise a highly topical theme that requires a deeper discussion. The title foresees that they will solve and discuss the problem from west to east. However, the interpretation of this problem appears to be simplified in the text and is based on only a few facts. From this perspective, a deeper look and a review of current soil health theories as well as a presentation of real examples would be needed.
Find attached detailed review comments.
Comments for author File: 
Comments.pdf
Author Response
Q2. Soil Health, as it is Now
In the introduction, authors draw attention to different terms – soil health, soil quality andsoil fertility. The explanation and use of all these terms should be more analyzed. Soil health as a term is explained and support by literature sources. However, it should be pointed out that definitions are based on an anthropocentric or ecosystem approach. Also definitions of other two terms (soil quality, soil fertility) should be added. Deeper comparison of term soil health with terms soil quality and soil fertility supported by adequate literature would contribute to better clarification. Such analysis would point to the common features and differences of those terms.
A2. We have added the following:
These definitions are anthropocentric in nature and takes an ecosystem viewpoint of soils. While soil health, soil fertility and soil quality are used loosely and interchangeably, soil quality and soil fertility have longer history of use and are particularly closely associated with agriculture. The definition of soil health has been relatively stable since the 2000s as indicated by the list of definitions collected by Mizuta et al.[6] and efforts are now focused more on operationalising it in terms of developing integrative approach to capture soil health in its entirety and complexity despite the questions remaining about the concept itself. …... The current contention of merits of soil quality over soil health have many similarities to the contentions with the concept of soil quality in the 1990s and we refer our readers to Sojka and Upchurch [7], Karlen et al.[8],], Karlen et al.[9], Mizuta et al.[6] and Bünemann et al.[10]to the evolution in terminology and concepts.
Q3. What Can Human Health Teach Us about Soil health?
Using human health as a metaphor for soil health is very interesting and illustrative. Then it would be possible to interpret soil degradation as soil diseases that could be caused by natural of anthropogenic factors. I would prefer to use the term healthfor living organisms. Although authors name soil as living system, soil is classified as an abiotic component of the environment. From such point of view, I see more suitable term soil quality that can be defined by set of appropriate indicators with limit values taking into account different evolution stages, supplied services as well as different potential capacities of different soils to buffer stress. Anyway the term soil health has been introduced into scientific literature with different explanations and meaning like authors present. From this point of view, the article is very useful and rises many open questions. The present is typical of the accumulation of new concepts, terms and their application in science is often subjective.
A3. The reviewer’s comments remind us of the argument over soil quality concept that occurred in the 1990s and where a series of publications seek to address these issues, from camp one - Karlen et al(2003, Soil quality: Humankind’s foundation for survival. Journal of Soil and Water Conservation58.: 171–179) and camp two - Sojka and Upchurch (1999, Reservations regarding the soil quality concept. Soil Science Society of America Journal63: 1039–1054). What is valid then remains very valid to the conversation that has now shifted from soil quality to soil health. Therefore, we have added:
The current contention of merits of soil quality over soil health have many similarities to the contentions with the concept of soil quality in the 1990s and we refer our readers to Sojka and Upchurch [7], Karlen et al.[8],], Karlen et al.[9], Mizuta et al.[6] and Bünemann et al.[10]to the evolution in terminology and concepts. We share the opinion expressed by Sojka and Upchurch [7] and Karlen et al.[8], that we must not let disagreement about terminology stand in the way of keeping our children and grandchildren fed, safe and healthy within the planetary boundary.
Q4. In the third paragraph of this chapter, author cited UNCCD work showing that land degradation is both a cause and a result of poverty. Related to this sentence it is necessary to add that land degradation can be also result or negative externality of economic growth (in developed countries) oriented especially on profit and neglected unrated and unpaid services (in case of soil e.g. regulating).
A4. We agree. The negative externalities occur both in developed and developing countries. As such, we added the following:
Land degradation can also be a result of economic growth that is oriented especially on profit and neglect the unrated and unpaid services, such as regulating services.
Q5. What Can Ecosystem Health Teach Us about Soil Health?
In this chapter, author critically looked at two similar concepts, ecosystem health and soil health. They pointed out the problem that can rise. It is necessary to take into account that soil itself can be evaluated as an ecosystem, and not only as a part of terrestrial ecosystems.
A5. Indeed, soil itself can be evaluated as an ecosystem. We have included it as follows:
Based on this definition of a healthy ecosystem, and taking into account that soil itself can be evaluated as an ecosystem, a healthy soil is able to maintain a certain level of structural (physical, chemical and biological) and functional integrity under changing environment.
Q6. The Practical Challenges of Operationalising Soil Health
Authors deal with agricultural soils and their main food provisioning services supporting by soil management what have negative impact on other services. Authors present case study from China and draw attention to negative consequences of overestimation of one (provisioning) service at the expense of other services and soil health. As a good examples authors present appropriate incentives and implementation of top-down policies for ecosystem subsidies to ensure soil health. I miss in this chapter more concrete practical measures that could be implemented not only in developing but also in developed countries. And author should pay attention also to forest soil or urban soil and their health and practical challneges.
A6.We have added concrete practical measures implemented in China. There were many measures implemented. These actual implementation are highly variable because they are determined by the local government. Taking that into consideration, we summarised the characteristics of success. The additions are as follows:
To these end, a series of measures were taken by the Ministry of Agriculture of China. Some of the successful practical measures include conservation tillage, national soil testing and fertilizer recommendation (STFR), straw return, and zero growth plan in chemical fertilizer use [27, 28]. These policies that have achieved some degree of success in promoting soil health share common features – they are national policies with central investment and legal instruments that were matched with local government’s investment, enforcement and locally-relevant concrete actions to implement the policies, and willing farmers. The latter, remains the most difficult factor to change in a country of 200 to 300 million smallholder farmers of diverse socioeconomic background. Subsidies in variable forms are critical, particulars in cash and fertilizers, as these smallholder farmers usually have low risk tolerance for change. These farmers also need to perceive clear gains; such as the case of clear sky when straw was returned instead of burnt. And finally, these changes need to be perceived as socially acceptable; such as the case of cover cropping in vineyard, whereby farmers were unwilling to implement it for fear of being perceived as lazy farmers by their community if the grounds are not kept clear of undergrowth.
We agree with the reviewer that the health of forest soil and urban soil and the practical challenges deserve attention and we deliberated over this in the initial drafts of this manuscript. The challenges to forest soils and urban soils are different to that of agriculture and we believe that deserved to be addressed separately. In this manuscript, we decided ultimately to focus on agricultural soils, which represent some 1/3 of total land area, and it is the epicentre of the current soil health debate.
Reviewer 2 Report
The present Ms was aiming to discuss about the concept of "Soil Health". Unfortunately, the reader gets quickly lost with a wording text without any illustrations (figures or tables), with a limited scientific content. There are very relevant and up-to-date review papers on "Soil Health” and they all discuss science and importance for agriculture. This does not exist in the present study.
Having said that, it becomes almost impossible to make specific comments as the whole Ms is subject to debate because of its content.
In conclusion, there is no obvious reason to recommend the present Ms for publication in an International scientific journal such as “Sustainability”.
Author Response
Q7: The present Ms was aiming to discuss about the concept of "Soil Health". Unfortunately, the reader gets quickly lost with a wording text without any illustrations (figures or tables), with a limited scientific content. There are very relevant and up-to-date review papers on "Soil Health” and they all discuss science and importance for agriculture. This does not exist in the present study. Having said that, it becomes almost impossible to make specific comments as the whole Ms is subject to debate because of its content.
In conclusion, there is no obvious reason to recommend the present Ms for publication in an International scientific journal such as “Sustainability”.
A7: We thank the reviewer for the comments. We are particularly glad that the reviewer is of opinion that the manuscript’s content is subject to debate because that is precisely the purpose of our discussion paper. It is our opinion that the concept of soil health has a wider reach beyond agriculture and it is therefore important to consider the fundamental challenges brought upon us by this term and the current iterations of definition of this term. The unique feature of the journal Sustainability is the broad audience base, and we hope our language is accessible to all to stimulate a broader discussion on soil health that goes beyond the science.
With regards to how our work fit into the context of the existing literature, we repeated the lit search. Using the keywords “soil health” AND review in Scopus, we extracted 193 papers from 2012 to 2019, of which 4 papers were related to the consideration of definition/ concept of soil health; the rest of the papers used the concept of soil health for various purpose including i) assessing agricultural management practices, ii) indicators/ tools for measuring soil health, iii) consequences of poor soil health etc. Almost all papers looked at soil health within agriculture or other production system, and none have taken the approach to look at soil health through the lens of human and ecosystem health. These two areas, in particular the human health develops very rapidly.
As reviewer 1 noted, we raised many questions, which is the aim of our discussion paper – to stimulate a discourse on fundamentals of the concept of soil health. The basis of progress in any science lies in the conceptual development. Yet in the context of soil health, its widespread use continues to be ahead of the fundamental development of the concept.
We are aware of the literature focus in the recent years on developing/ refining indicators. We do not wish to produce another iteration of this discussion at this point when others have done so well in this. But this development brings us back to the importance of the conceptual development of soil health as the philosophy of choice for managing a finite resource. What we measure decides what we do, and if our measurements are flawed, decisions that we make too may be biased. When we examine the current concept through the lens of human health and ecosystem health, there is a clear mismatch between our idealised soil health, and the reality of tradeoffs we are making to achieve an ecosystem state of high vigor.
There are dimensions of health that are hard to be measured currently, and our discussion attempts to bring to light the fundamental and practical challenges involved as scientists working with land managers to protect a common good. For example, we believe there are ethical and philosophical components that are brought to light when we consider soil health from the perspective of human health; e.g. A healthy soil determined purely on its ability to supply goods is equivalent to measuring human health based on the person’s ability to do work, or the person’s economic value as a member of the society.We believed this fits the journal’s aim –Ethical and philosophical aspects of sustainable development, which we think is often neglected when we talk about soil health from an purely soil science perspective.
Author Response File: 
Author Response.docx
Reviewer 3 Report
The article concerns an important issue which is Soil Health. However, in my opinion, it is not enough scientific to be published in Sustainability. The presented content does not bring any new, valuable information regarding the issue related to "Soil Health".
The paper that I reviewed needs to be rewritten. It is not acceptable in its current form. I think that the authors should include more specific data related to the soil quality (e.g. the indicators, the quality standards). In the literature we can find a lot of articles about this subject. The authors focused only on the definitions which does not bring anything new and interesting to the soil quality subject. The indicators mentioned by the authors should be described numerically- it may increase the value of the article.
Author Response
Q1. The article concerns an important issue which is Soil Health. However, in my opinion, it is not enough scientific to be published in Sustainability. The presented content does not bring any new, valuable information regarding the issue related to "Soil Health".
The paper that I reviewed needs to be rewritten. It is not acceptable in its current form. I think that the authors should include more specific data related to the soil quality (e.g. the indicators, the quality standards). In the literature we can find a lot of articles about this subject. The authors focused only on the definitions which does not bring anything new and interesting to the soil quality subject. The indicators mentioned by the authors should be described numerically- it may increase the value of the article.
The authors raised a highly topical theme that requires a deeper discussion. They raised many interesting questions. The title foresees that they will solve and discuss the problem from west to east. However, the interpretation of this problem appears to be simplified in the text and needs deeper analysis and more examples illustrating fundamental and practical challenges to sustainably manage soil health.
A1: In light of the comments of both reviewers that we did not offer anything new and interesting, we rerun the literature search. Using the keywords “soil health” AND review in Scopus, we extracted 193 papers from 2012 to 2019, of which 4 papers were related to the consideration of definition/ concept of soil health; the rest of the papers used the concept of soil health for various purpose including i) assessing agricultural management practices, ii) indicators/ tools for measuring soil health, iii) consequences of poor soil health etc. Almost all papers looked at soil health within agriculture or other production system, and none have taken the approach to look at soil health through the lens of human and ecosystem health. These two areas, in particular the human health develops very rapidly.
As the reviewer correctly noted, we raised many questions, which is the aim of our discussion paper – to stimulate a discourse on fundamentals of the concept of soil health. The basis of progress in any science lies in the conceptual development. Yet in the context of soil health, its widespread use continues to be ahead of the fundamental development of the concept.
We are aware of the literature focus in the recent years on developing/ refining indicators. We do not wish to produce another iteration of this discussion at this point when others have done so well in this. But this development brings us back to the importance of the conceptual development of soil health as the philosophy of choice for managing a finite resource. What we measure decides what we do, and if our measurements are flawed, decisions that we make too may be biased. When we examine the current concept through the lens of human health and ecosystem health, there is a clear mismatch between our idealised soil health, and the reality of tradeoffs we are making to achieve an ecosystem state of high vigor.
There are dimensions of health that are hard to be measured currently, and our discussion attempts to bring to light the fundamental and practical challenges involved as scientists working with land managers to protect a common good. For example, we believe there are ethical and philosophical components that are brought to light when we consider soil health from the perspective of human health; e.g. A healthy soil determined purely on its ability to supply goods is equivalent to measuring human health based on the person’s ability to do work, or the person’s economic value as a member of the society.We believed this fits the journal’s aim –Ethical and philosophical aspects of sustainable development, which we think is often neglected when we talk about soil health from an purely soil science perspective.
We have also changed the title to In search of the meaning of soil health: lessons from human health and ecosystem health.
Round 2
Reviewer 1 Report
No further comments and suggestions. I agree with the text in present form.
Reviewer 3 Report
Dear Authors,
I see a significant improvement in the manuscript. I will recommend the acceptance.
I suggest that the authors in the next work devoted to this issue develop a universal system of assessing soil health, so that you can assess the health of soils in various regions of the world on a simple score-scale.
Best regards,
Reviewer
