Review Reports - Application of Ecological Restoration Technologies for the Improvement of Biodiversity and Ecosystem in the River

Round 1

Reviewer 1 Report

The authors present a review of the river restoration technologies for the improved management of the river ecosystems. The review is very difficult to follow, not structured and organised well and needs proof reading by professionals. The topic fits well within the scope of the Water journal, however needs significant improvement for which I suggest major revisions.

Main Comments

1. My major concern with the manuscript is the use of the terms river technologies or river restoration technologies. Secondly, is it actually right to use the term technology? because what the authors are talking about are the techniques or methods for river restoration. The authors are strongly advised to ensure what terminology they are using and be clear about them.

2. In Section 2 Definition and concept of river restoration is actually missing the "definition" of river restoration. In this section I would expect reading different definitions provided in the literature and a review of them.

3. Figure 1 caption is not clear. I am not sure what does the caption "Core elements, structures and functions of river" mean. One of the main functions of the river involves biogeochemical processes/ water chemistry and it has not been mentioned. I assume authors put this under "self purification", however its not clear from the text.

4. Within Section 3, the information provided is vague. For example, the sentence " Human fishing directly affects the kinds of fish.". I do not understand what the authors mean by this?

5. Section 4 is not structured well and is very difficult to follow and understand. There's no introduction of different restoration methods between the lines 150 - 176. The authors mention something about "Ecological engineering" without giving a context. Several sentences are very confusing such as in lines 173 - 176 " Thus, the ecological impacts of river restoration technologies on rivers are so complicated that critically identifying characteristics of river restoration technologies is one key of the river restoration." I do not understand what the authors would like to convey?

Furthermore, I do not understand the use of term "shipping" in line 228 "Channels is the basic attributes, characterized by the function of shipping." Please clarify.

6. In the Table 1 and Table 2, I do not understand why the authors do not discuss all the river restoration methods. Why the advantages and disadvantages of Dam removal/Retrofit, Biological Water Purification Technologies and Bio-Chain Reconstruction not mentioned? In Table 2, there a mention of vegetation restoration method, which method is this? Are the authors discussing about Catchment revegetation? Please be consistent with the terms, otherwise it is very confusing for the readers.

Author Response

Reviewer #1:

Main Comments

My major concern with the manuscript is the use of the terms river technologies or river restoration technologies. Secondly, is it actually right to use the term technology? because what the authors are talking about are the techniques or methods for river restoration. The authors are strongly advised to ensure what terminology they are using and be clear about them.
Response:

Thanks for your suggestion. Ecological restoration is the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed (SER 2004). Based on this definition, restoration seeks to recover an ecosystem's ecological structure and function, including its biotic integrity. The term of ecological restoration technologies (ERTs) was used in the previous studies (Zhen et al. 2020).

Reference

SER (Society for Ecological Restoration), 2004. The SER International Primer on Ecological Restoration. (Tucson, Arizona).

Zhen L, Ishwaran N, Luo Q, et al. Role and significance of restoration technologies for vulnerable ecosystems in building an ecological civilization in China[J]. Environmental Development, 2020, 34: 100494.

In Section 2 Definition and concept of river restoration is actually missing the "definition" of river restoration. In this section I would expect reading different definitions provided in the literature and a review of them.

Response:
The term of “river restoration” was replaced with ‘Ecological restoration’ in the river.

‘Ecological restoration technologies’ in the river was defined in the section 2.

Ecological restoration in the river is the process of recovering the degraded, damaged, and destroyed ecosystem of river through restoring the ecological structure, function and biotic integrity (SER 2004; Zhen et al. 2020).

Reference

SER (Society for Ecological Restoration), 2004. The SER International Primer on Ecological Restoration. (Tucson, Arizona).

Figure 1 caption is not clear. I am not sure what does the caption "Core elements, structures and functions of river" mean. One of the main functions of the river involves biogeochemical processes/ water chemistry and it has not been mentioned. I assume authors put this under "self purification", however its not clear from the text.

Response:
The note about processes, structures and functions of river was added in the manuscript.

According the valuable suggestion, the information about biogeochemical processes was also added in the Fig 1. We also made minor modification in the Fig 1.

Fig 1 Processes, structures and functions of river. Processes are associated with physical, chemical and biological processes in the river. Structure is linked with the composition in the river. Function is that river provide the uses on human beings or society.
4. Within Section 3, the information provided is vague. For example, the sentence " Human fishing directly affects the kinds of fish.". I do not understand what the authors mean by this?

Response:
This sentence was replaced with ‘the kinds of fish are linked with human fishing due to the high consumption of certain fish by humans’.
5. Section 4 is not structured well and is very difficult to follow and understand. There's no introduction of different restoration methods between the lines 150 - 176. The authors mention something about "Ecological engineering" without giving a context. Several sentences are very confusing such as in lines 173 - 176 " Thus, the ecological impacts of river restoration technologies on rivers are so complicated that critically identifying characteristics of river restoration technologies is one key of the river restoration." I do not understand what the authors would like to convey?
Furthermore, I do not understand the use of term "shipping" in line 228 "Channels is the basic attributes, characterized by the function of shipping." Please clarify.

Response:

The structure of sentences has been revised.

In line 150 – 176, the content of River Restoration Technologies generally related to ‘Ecological Engineering’ was added.

In the line 173-176, the content was replaced with ‘Thus, the ecological impacts of river restoration technologies on rivers are so various that critically identifying characteristics of river restoration technologies is the key of the river restoration’.
In line 228, this sentence was replaced with “Channels in the river provides the available function of shipping for the shipping”.

In the Table 1 and Table 2, I do not understand why the authors do not discuss all the river restoration methods. Why the advantages and disadvantages of Dam removal/Retrofit, Biological Water Purification Technologies and Bio-Chain Reconstruction not mentioned? In Table 2, there a mention of vegetation restoration method, which method is this? Are the authors discussing about Catchment revegetation? Please be consistent with the terms, otherwise it is very confusing for the readers.

Response:

The advantages and disadvantages of river restoration technologies has already been stated in the manuscript, and re-tabulation will cause repetition. However, the advantages and disadvantages of Dam removal/Retrofit was added in the manuscript. Biological Water Purification Technologies was various. Most of the technologies in our manuscript was related wo the water purification. Thus, it is not reasonable to list the advantages and disadvantages of biological water purification technologies. The advantages and disadvantages of Bio-Chain Reconstruction was present in the content, so the table was not showed in the manuscript. Vegetation restoration help enhance the plant cover in the river through replanting, transplanting mature plants into the river, especially along the river bank. Catchment revegetation was deleted.

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper:

„Application of river restoration technologies for the improvement of biodiversity and ecosystem“

The paper brings river restoration techniques on the element reproduction are more helpful to promote the restoration of the natural appearance and function of the river.

The literature review is good showing the relative broad horizons of the authors.

The main idea is establishing a unified river health evaluation system will help to promote a virtuous cycle of positive feedback of healthy rivers and the further development of river restoration technologies.

Theoretical knowledge contributes to this scientific field. I have some questions, comments:

Specific comments or questions:

Abstract – of about 200 words maximum …. Can you edit this paragraph? It has 299 words
Introduction:
Ecological Flow Modification – processes such as water erosion, sediment transport (together with pesticides, harmful substances, heavy metals ...). environmental hazards should also be addressed
The reservoirs have problems with sediment, the process of clogging (volume reduction). flood protection does not meet the criteria (long-term plan)
Environmental flow is equivalent to ecological flow? Minimum flow .... how are the flows defined?
discussion? Conclusion?

The editors must decide on the possibility of publishing the article

Author Response

Reviewer 2#

The paper brings river restoration techniques on the element reproduction are more helpful to promote the restoration of the natural appearance and function of the river. The literature review is good showing the relative broad horizons of the authors. The main idea is establishing a unified river health evaluation system will help to promote a virtuous cycle of positive feedback of healthy rivers and the further development of river restoration technologies. Theoretical knowledge contributes to this scientific field. I have some questions, comments:

Specific comments or questions:

Abstract – of about 200 words maximum …. Can you edit this paragraph? It has 299 words.

Response:

The Abstract was reduced to 198 words.

Introduction:

Ecological Flow Modification – processes such as water erosion, sediment transport (together with pesticides, harmful substances, heavy metals ...). environmental hazards should also be addressed. The reservoirs have problems with sediment, the process of clogging (volume reduction). flood protection does not meet the criteria (long-term plan)

Response:

We agree with the opinion of review. The content of ‘Environmental hazards include water erosion, sediment transport together with pesticides, harmful substances, heavy metals’ was added in the section 4.1.1.

Environmental flow is equivalent to ecological flow? Minimum flow .... how are the flows defined?

Response:

"Flow" specifically refers to the flow of water in the river, that is, the amount of water passing through a section of the river in a unit time (usually m³/s).

The European Union's Water Framework Directive in 2000 defined ecological flow as the amount of water needed to maintain the health of aquatic ecosystems and provide the services we rely on.

In 2010, The Nature Conservancy in the United States defined environmental flow, that is, to maintain the components, functions, processes and elasticity of water ecosystems, and to determine the amount and time scale of water amount to meet human material and service needs.

Minimum Flow is defined as "the minimum flow in the river that maintains the basic morphology and ecological functions of the river.

Theses phrases of ‘Environmental flow’ & ‘ecological flow’ was replaced with ‘ecological water transfer’.

discussion? Conclusion? The editors must decide on the possibility of publishing the article.

Response:

In the section “River management”, the contents include the discussion.

The concepts of ERTs and management are interrelated. Generally, the theory of management contributes to identify strengths and weaknesses in ERTs and enhance the improvement of ERTs. The management of ERTs play an important role on the improvements of river health. Taking into account the macro theory of the management of the restoration in a basin is conducive to the restoration of the biodiversity in the river watershed.

We conclude the problems of ERTs and the management of ERTs. In addition, several prospects were provided in the manuscript.

We changed the structure of this mini review according to the demand of our manuscript.

We hope the approval from the reviewers and editors. Many thanks.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Authors have addressed my concerns in a satisfactory way. I still think English can be improved.

Reviewer 2 Report