Spatio-Temporal Evolution and Optimization of Ecospatial Networks in County Areas Based on Ecological Risk Assessment: Taking Dalian Pulandian District as an Example
Round 1
Reviewer 1 Report
This is a typical case study in the construction and optimization of eco-spatial networks both in terms of the methodology and results and discussions. The current manuscript reflects a certain amount of work, but there are major problems with the text, especially in academic expression, where many errors have occurred. I'd recommend a major revision and the specific comments include, but are not limited as follows:
1. Title: Problem with consistency in word capitalization, as ‘Example’.
2. Abstract: Errors of repetitive expressions, as ‘…. and evaluate its ecological risk from the socioeconomic and environmental aspects to provide a basis for the construction of ecological resistance surfaces. -environmental aspects to assess its ecological risk to provide a basis for the construction of ecological resistance surface. …’. What happened to the authors at the time of submission to produce such a rudimentary error? Future submissions should be double-checked to avoid the appearance of errors that affect reading, which will inevitably negatively influence the reviewers' judgment of the authors' academic standards and level.
3. Abstract: Poor English academic expression of ‘Restoring the seven ecological sources in the central and southern regions increases the area, optimizing the number of ecological corridors to 66, and proposing an ecological spatial network optimization system of “one barrier and belt, multiple corridors and nodes”’. It is a puzzling sick sentence with incomplete components here, and what are the authors trying to say?
4. In addition, the entire Abstract is difficult to follow owing to the cumbersome formulations and confusing tenses, which must be refined and modified to enhance the brevity and accuracy of the language.
5. Keywords: Problem with consistency in word capitalization, as ‘ecological risk’.
6. I noticed that the authors referred to ‘coastal counties’ in both Title and Keywords. However, in reality, although the study area is coastal, this work is not uniquely innovative in terms of ecological risk assessment and ecological network construction in coastal areas, and it would not be appropriate to place special emphasis on it as a keyword.
7. Introduction: Problems with abbreviation. MSPA should be placed in parentheses when it is first mentioned, the same issue occurs with the DPSR and some error clearly shown in the sentence ‘this study combines the relevant literature [2-4,9-10] and utilizes the driving force-pressure-status (State) method[15]. -State-Impact-Response DPSIR model to …’. Furthermore, why did the MCR model use the acronym directly in the first reference while instead using the full (defining abbreviations) form when mentioned the second time? This is completely opposite to correct writing! The authors’ academic expression is very irregular.
8. Introduction: ‘For the study of ecological spatial net-work in coastal areas, foreign countries mainly focus on ecological security evaluation and regional planning based on ecosystems [19-20], and the progress of domestic research is also gradually shifted from ecosystem evaluation to the development of ecological spatial pattern, with more regions involving Guangdong, Hong Kong, Macao and the Greater Bay Area in the East China Sea region, Ningbo, and Sanya, etc. [21-24].’, this kind of expression is inappropriate and must be revised. Do not bring the expression habits of Chinese writing into English writing!
9. Introduction: Errors of repetitive expressions, as ‘but also has an important role in the stabilization and maintenance of the ecological environment and biodiversity, and the promotion of the harmonious development of man and nature [16]. It also plays an important role in stabilizing and maintaining the ecological environment and biodiversity, and promoting the harmonious development of human beings and nature [16].’ What happened? This is the second such mistake, and at this moment I’m worried that it might come up again later. Authors must double-check themselves before submitting the manuscript!
10. Introduction: Unable to summarize the situation and shortcomings of existing studies in a straightforward manner and, as a result, to present the innovativeness of this study. As far as I understand, the two main innovations that the authors rely on are the scale and object of the study in coastal counties, and the research methodology of assisting in the construction of ecological networks through ecological risk assessment that actually only plays a role in generating ecological resistance surfaces. These are only mentioned in the Introduction without being highlighted, leaving the reader with a poor understanding of the study’s innovations.
11. In addition, it is important to note that the coastal object and the county scale do not play any special role in the methodology, discussion, or conclusion of this work, but merely add a case of relevant research in this area. In that case, the authors should have at least compared the similarities and differences between ecological network construction and optimization in coastal county areas and non-coastal urban areas in the discussion, otherwise it could not have been made a special point, especially as the authors also highlighted both the Title and Keywords, which would have made the focus of this work unclear. This comment is related to comment 6 and can be comprehensively understood.
12. Materials and Methods: Problem with consistency in word capitalization, as ‘2.1. study Area’ and ‘population density, urbanization rate’ in Table 1.
13. Materials and Methods: There should be a space between the number and the length/area unit and the square of the area should be in superscript format. The entire text should be checked and modified.
14. Materials and Methods: What are the formulas for Ci, Ni, and Di? As far as I know, there are many different calculation methods for these three indices in the existing study, and they should be clarified here instead of just labeling the references.
15. Materials and Methods: Once again, there is an error regarding repetitive expressions, as ‘... and the advantage of MSPA analysis is that it emphasizes the structural connectivity of the network, which can better promote the flow of material information and energy [7-9,22], and helps to scientifically select ecological source areas and corridors. The MSPA analysis method has the advantage of emphasizing the structural connectivity of the network, better facilitating the flow of material information and energy [7-9], and helping to scientifically select ecological source sites and corridors’.
16. The conclusion should provide readers with very direct information, a highly condensed and summarized account of the results, and some insights gained through the Discussion, rather than a redundant summary presentation of the results.
17. References: The reference format is not standardized in a number of ways, including word capitalization, spaces, and coding of document types. It is recommended that the authors use a literature management tool to standardize the formatting of references and take into account the requirements of the journal. These are details, but they reflect the level of attention the authors have paid to this manuscript, which seems to be insufficient at present.
18. The English expression in the current manuscript is headache-inducing and requires further revision and refinement before it can be accepted and published as a competent academic research article.
The English language and expression in the current manuscript is headache-inducing and requires further revision and refinement before it can be accepted and published as a competent academic research article.
Author Response
Dear Reviewers：
Thank you very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! We have tried our best to improve and made some changes in the manuscript.Please find my itemized responses in below.
Point 1:
Title: Problem with consistency in word capitalization, as ‘Example’.
Response 1:
Thank you for your suggestion, we apologize for the error, the corrected title is as follows:
Spatio-Temporal Evolution and Optimization of EcoSpatial Networks in County Area Based on Ecological Risk Assess-ment: Taking Dalian Pulandian District as an Example
Point 2:
Errors of repetitive expressions, as ‘…. and evaluate its ecological risk from the socioeconomic and environmental aspects to provide a basis for the construction of ecological resistance surfaces. -environmental aspects to assess its ecological risk to provide a basis for the construction of ecological resistance surface.
Response 2:
We apologize for giving you such a bad reading experience, we had intended to choose the better of the two translations but inadvertently kept both sentences, again, we apologize for our negligence!
Point 3:
Poor English academic expression of ‘Restoring the seven ecological sources in the central and southern regions increases the area, optimizing the number of ecological corridors to 66, and proposing an ecological spatial network optimization system of “one barrier and belt, multiple corridors and nodes”’.
Response 3:
Sorry for the bad experience, but the sentence contained a Chinese acronym that made it difficult to translate, so we had to drop the acronym and re-translate the sentence in order to make it work.
Therefore, seven new ecological source sites were added for the central and southern portions of the study area, and the number of optimized ecological corridors increased from 47 to 66. In addition, we established an ecosystem consisting of an ecological barrier, an ecological coastal zone, multiple ecological corridors, and multiple ecological sites as an optimization system.
Point 4:
In addition, the entire Abstract is difficult to follow owing to the cumbersome formulations and confusing tenses, which must be refined and modified to enhance the brevity and accuracy of the language.
Response 4:
Thank you very much for your advice. We apologize for this grammatical problem and have corrected it based on your suggestions. In addition, we have Invited English editors to polish and modify the manuscript.
Point 5:
Keywords: Problem with consistency in word capitalization, as ‘ecological risk’.
Response 5:
The case problem in keywords has been corrected, as ‘ecological risk’.
Point 6:
I noticed that the authors referred to ‘coastal counties’ in both Title and Keywords. However, in reality, although the study area is coastal, this work is not uniquely innovative in terms of ecological risk assessment and ecological network construction in coastal areas, and it would not be appropriate to place special emphasis on it as a keyword.
Response 6:
After carefully considering your suggestion we have removed the term ‘coastal counties’ from the title and keywords. The corrected title is Spatio-Temporal Evolution and Optimization of EcoSpatial Networks in County Areas Based on Ecological Risk Assess-ment: Taking Dalian Pulandian District as an Example. and the corrected keywords are evaluation indicators; analysis of spatial patterns; ecological risk; Pulandian.
Point 7:
Introduction: Problems with abbreviation. MSPA should be placed in parentheses when it is first mentioned, the same issue occurs with the DPSR and some error clearly shown in the sentence ‘this study combines the relevant literature [2-4,9-10] and utilizes the driving force-pressure-status (State) method[15]. -State-Impact-Response DPSIR model to …’. Furthermore, why did the MCR model use the acronym directly in the first reference while instead using the full (defining abbreviations) form when mentioned the second time? This is completely opposite to correct writing! The authors’ academic expression is very irregular.
Response 7:
The above issues have been corrected in the manuscript.
Point 8:
Introduction: ‘For the study of ecological spatial net-work in coastal areas, foreign countries mainly focus on ecological security evaluation and regional planning based on ecosystems [19-20], and the progress of domestic research is also gradually shifted from ecosystem evaluation to the development of ecological spatial pattern, with more regions involving Guangdong, Hong Kong, Macao and the Greater Bay Area in the East China Sea region, Ningbo, and Sanya, etc. [21-24].’, this kind of expression is inappropriate and must be revised. Do not bring the expression habits of Chinese writing into English writing!
Response 8:
Thank you for your suggestion, we have modified the original text and re-translated it to match the English expression.
Point 9:
Introduction: Errors of repetitive expressions, as ‘but also has an important role in the stabilization and maintenance of the ecological environment and biodiversity, and the promotion of the harmonious development of man and nature [16]. It also plays an important role in stabilizing and maintaining the ecological environment and biodiversity, and promoting the harmonious development of human beings and nature [16].’ What happened? This is the second such mistake, and at this moment I’m worried that it might come up again later. Authors must double-check themselves before submitting the manuscript!
Response 9:
We apologize for our oversight and will recheck the manuscript
Point 10:
Introduction: Unable to summarize the situation and shortcomings of existing studies in a straightforward manner and, as a result, to present the innovativeness of this study. As far as I understand, the two main innovations that the authors rely on are the scale and object of the study in coastal counties, and the research methodology of assisting in the construction of ecological networks through ecological risk assessment that actually only plays a role in generating ecological resistance surfaces. These are only mentioned in the Introduction without being highlighted, leaving the reader with a poor understanding of the study’s innovations.
Response 10：
We've added a few things to make this clear.
this study combines the relevant literature [2-4,9-10] and utilizes the DPSIR model to as-sess the ecological risk estimation and incorporate ecosystem services into the DPSIR model, which highlights that ecological changes affect ecological services and also con-siders the cost-effectiveness in relation to social well-being. From the perspective of ecospa-tial network construction, most studies utilize the MCR model to construct resistance sur-faces, and construct ecospatial networks based on ecological security evaluation [15-16,27], ecosystem service assessment [22-23], and ecological sensitivity evaluation [26-27], while there are still relatively few studies on the construction of ecospatial networks from the ecological risk perspective. Constructing an ecospatial network from the perspective of ecological risk can better identify and assess the risks to the ecological environment. This new ecological environment management approach organically integrates the relationship between the ecological environment and various aspects of human society and economic activities, which can more comprehensively identify and assess the risks of the ecological environment and provide a basis for formulating a more scientific and rational ecological environment management strategy.
Point 11:
In addition, it is important to note that the coastal object and the county scale do not play any special role in the methodology, discussion, or conclusion of this work, but merely add a case of relevant research in this area. In that case, the authors should have at least compared the similarities and differences between ecological network construction and optimization in coastal county areas and non-coastal urban areas in the discussion, otherwise it could not have been made a special point, especially as the authors also highlighted both the Title and Keywords, which would have made the focus of this work unclear. This comment is related to comment 6 and can be comprehensively understood.
Response 11:
Thank you for your suggestion, we have changed the title and keywords based on the previous question and added something to the discussion section to show the importance of using the county as the subject of the study.
At the same time, county-level administrative units, as the fusion zones of industry and agriculture, and of urban and rural areas in China, are able to provide enormous support in terms of capital, land, labor and other resources for the development of regional central cities, and are also the key to integrating the development of urban and rural areas in Chi-na and to consolidating and safeguarding the basic power of the people.
Point 12:
Materials and Methods: Problem with consistency in word capitalization, as ‘2.1. study Area’ and ‘population density, urbanization rate’ in Table 1.
Response 12:
The capitalization problem in table1 has been corrected
study Area Study Area ‘population density, urbanization rate’ ‘Population density, Urbanization rate’
Point 13:
Materials and Methods: There should be a space between the number and the length/area unit and the square of the area should be in superscript format. The entire text should be checked and modified.
Response 13:
We have corrected the above mistakes, thank you for your careful review!
Point 14:
Materials and Methods: What are the formulas for Ci, Ni, and Di? As far as I know, there are many different calculation methods for these three indices in the existing study, and they should be clarified here instead of just labeling the references.
Response 14:
We have added formulas and paraphrases in the text for c, n, d
where ni is the number of patches of landscape type i , and Ai is the area of landscape type i ; its value is used to express the stability and degree of fragmentation of the internal units of the landscape, and the smaller the value, the higher the stability of the internal units of the landscape and the smaller the degree of fragmentation.
where Ai is the total area of landscape type i ; Li is the distance index of landscape type i ; ni is the number of patches of landscape type i ; and A is the total area of the landscape, the value of which expresses the degree of separation of the individual distribution of different elements or patches of a certain landscape type, and the greater the degree of separation, the more complex the distribution of the landscape, and the more dispersed the landscape is in terms of geographical distribution.
where Rd is the density, Rf is the frequency, and Lp is the proportion of the landscape. The dominance value plays a significant role in the analysis of the spatial structure of the landscape pattern, and can be used to judge the dominance of a certain block type in the landscape.
Point 15:
Materials and Methods: Once again, there is an error regarding repetitive expressions, as ‘... and the advantage of MSPA analysis is that it emphasizes the structural connectivity of the network, which can better promote the flow of material information and energy [7-9,22], and helps to scientifically select ecological source areas and corridors. The MSPA analysis method has the advantage of emphasizing the structural connectivity of the network, better facilitating the flow of material information and energy [7-9], and helping to scientifically select ecological source sites and corridors’.
Response 15:
The duplicates have been removed, and again, we apologize for the error!
Point 16:
The conclusion should provide readers with very direct information, a highly condensed and summarized account of the results, and some insights gained through the Discussion, rather than a redundant summary presentation of the results.
Response 16:
Thank you for your suggestion, as suggested we have summarized and rewritten the conclusion section
Point 17:
References: The reference format is not standardized in a number of ways, including word capitalization, spaces, and coding of document types. It is recommended that the authors use a literature management tool to standardize the formatting of references and take into account the requirements of the journal. These are details, but they reflect the level of attention the authors have paid to this manuscript, which seems to be insufficient at present.
Response 17:
We apologize for such an error and we will recheck the references section
Point 18:
The English expression in the current manuscript is headache-inducing and requires further revision and refinement before it can be accepted and published as a competent academic research article.
Response 18:
We are very sorry to have brought you such a bad reading experience, and we will do our best to remedy the situation regarding the English expression, including but not limited to seeking the help of a professional English editor.
Reviewer 2 Report
I am happy to review the manuscript. I think the manuscript need some minor corrections as below.
1. Study area is obscure. International audience can not identify the study area without its country name both in text and figure 1. The caption of the figure 1 should modify and try to write it more meaningful way.
2. Authors should mention the landuse source in the result section as well both in text and in the figure 2, as they mentioned in the materials and methods.
3. In the conclusion section, numbering can be omitted.
4. Landuse data were taken from other works, and missing the consent or data availability of these data.
Author Response
Dear Reviewers：
Thank you very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! We have tried our best to improve and made some changes in the manuscript.Please find my itemized responses in below.
Point 1:
Study area is obscure. International audience can not identify the study area without its country name both in text and figure 1. The caption of the figure 1 should modify and try to write it more meaningful way.
Response 1:
Thanks to your suggestions, we have redrawn Figure 1, using a higher resolution image, added country names, coordinates and renamed the title to Geographical location of the study area.
Point 2:
Authors should mention the landuse source in the result section as well both in text and in the figure 2, as they mentioned in the materials and methods.
Response 2:
Thank you very much for your suggestion, we have added this aspect to the corresponding section of the manuscript.
Point 3:
In the conclusion section, numbering can be omitted.
Response 3:
Thank you very much for your suggestion,The numbering in the conclusions has been deleted.
Point 4:
Landuse data were taken from other works, and missing the consent or data availability of these data.
Response 4:
A portion of the land use data used in the paper are derived from the dataset published by Prof. Yang and Prof. Huang, which is publicly available data.
Reviewer 3 Report
It is not clear what data the authors worked with. In the data series, the author refers to the data: "The dataset created by Yang and Huang [25] served as this study’s data source for land use information", however, this source mentions the year of publication 2008, which does not correspond to the analyzed data series. Even other links to databases (https://www.casdc.cn/ and https://www.tianditu.gov.cn) are not relevant and do not allow to verify specific data series. In addition, these sources are not listed in the bibliography. I recommend authors to specify data sources so that they are verifiable.
It is not clear enough in the tables how the authors obtained the relevant values, for example in table 1 I would like more detailed information about the values of the individual weights and the justification of the standardized layer and indicator layer used, it is not possible to just refer to the literature.
In the article, I lack familiarity with methods of analysis, I consider only references to literary sources to be insufficient.
There are minor formal flaws in the thesis, for example, the text lacks a reference to literature 29, on page 15 there is a link to table 6-18, a reference to table 4 and figure 2 is missing, images and tables are formatted outside the document margins, etc.
The conclusion, especially point 1, is too general, it is not clear what these conclusions and research results are for. I recommend adding in the contribution, on the basis of which research question, or hypothesis, the research was carried out.
Author Response
Dear Reviewers：
Thank you very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! We have tried our best to improve and made some changes in the manuscript.Please find my itemized responses in below.
Point 1:
It is not clear what data the authors worked with. In the data series, the author refers to the data: "The dataset created by Yang and Huang [25] served as this study’s data source for land use information", however, this source mentions the year of publication 2008, which does not correspond to the analyzed data series. Even other links to databases (https://www.casdc.cn/ and https://www.tianditu.gov.cn) are not relevant and do not allow to verify specific data series. In addition, these sources are not listed in the bibliography. I recommend authors to specify data sources so that they are verifiable.
Response 1:
Dear reviewer, We are very grateful for your suggestion.The download address of the dataset mentioned in the paper is (https://zenodo.org/record/5210928#.Y2dDTctByUk).
The cited literature is written by Prof. Yang and Prof. Huang 30m annual land cover and its dynamics in China from 1990 to 2019.
We apologize for using the wrong database link, it has now been corrected to （https://www.gscloud.cn/).
Point 2:
It is not clear enough in the tables how the authors obtained the relevant values, for example in table 1 I would like more detailed information about the values of the individual weights and the justification of the standardized layer and indicator layer used, it is not possible to just refer to the literature.
Response 2:
Thanks to your suggestion, we have added more detailed information to section 2.2
In the process of selecting indicators, on the one hand, it is necessary to consider whether the indicators can scientifically reflect the current situation of the ecosystem, to ensure that they are not repeated, too limited or too simple, and to ensure that the indicators have a certain degree of representativeness and comprehensively reflect the characteristics of the ecosystem. On the other hand, the indicators of the statistical system were selected as far as possible to ensure the accessibility and authenticity of the data. This paper took the connotation of ecological risk as the starting point, combined the actual situation of the socio-economic environment and ecosystem in the study area, and established an evaluation index system by selecting 14 index factors from 3 aspects, namely natural factors, economic factors and social factors.
Point3:
There are minor formal flaws in the thesis, for example, the text lacks a reference to literature 29, on page 15 there is a link to table 6-18, a reference to table 4 and figure 2 is missing, images and tables are formatted outside the document margins, etc.
Response 3:
Due to negligence I mistakenly wrote literature 29 as 25. This has now been corrected；Table 6-18 has been corrected to read table 4；Figure 2 added to the end of section 3.1
The dataset created by Yang and Huang[25] served as this study’s data source for land use information. The land use data for 1990, 2000, 2010, and 2020 (spatial resolution 30 m)
The dataset created by Yang and Huang served as this study’s data source for land use information. The land use data for 1990, 2000, 2010, and 2020 (spatial resolution 30 m) [29]
Point 4:
The conclusion, especially point 1, is too general, it is not clear what these conclusions and research results are for. I recommend adding in the contribution, on the basis of which research question, or hypothesis, the research was carried out.
Response 4:
The following has been added to the first part of the conclusions to illustrate the contribution that the results of the study can make
on this basis, the ecological spatial network optimization model for reducing ecological risk and satisfying ecological safety was constructed and optimized. This provides a theoretical basis for further enhancing the ecological security status of the study area, truly playing the role of protecting the ecological barrier of the coastal zone, and providing a theoretical basis for decision-making regarding ecological environment construction in the study area and other related departments in relevant counties.
Reviewer 4 Report
The manuscript applies various methods such as the DPSIR model, the MCR model, the MSPA model, and the circuit theoretical model to construct a model that reduce ecological risk and meet ecological security. I suggest that authors propose a prediction based on their argument "relatively few studies on the construction of ecospatial networks from the ecological risk perspective". The authors propose to implement an optimization, which should be presented in the introduction. Section 3.1 of the results includes the inputs to generate the optimized model, so I suggest present them in annexes or supplementary files and report the most important. The discussion is insufficient, I consider that the authors can discuss the advantages and limitations of using an optimized model. As well as propose new studies that would have to be carried out to support or expand their results.
Keywords
I suggest that authors use words other than those included in the title. The key words represent the content of your manuscript and be specific to your field or sub-field. Use different words from title will increase the number of people reading your manuscript, and likely lead to more citations.
Introduction
I suggest that the authors present a hypothesis based on their argument "relatively few studies on the construction of ecospatial networks from the ecological risk perspective" (page 3). For example, how much can the model be improved by implementing the ecological risk perspective. optimization of ecological patterns.
Methods
Specify that Liaodong peninsula is in China (page 4, section 2.1). Include coordinates on maps.
Explain what the combination of entropy weight method and mean square deviation decision-making method.
Describe ecological service value, ecosystem biomass factor, landscape fragmentation Ci, landscape separation Ni, and landscape dominance Di
MSPA describe the acronym.
Include reference of Guidos Toolbox software
Results
I consider that section 3.1 corresponds to the inputs to perform the optimization of ecological patterns, so I suggest that it be included as an appendix. The description of this section is monotonous and distracts from the main topic, so I suggest that only the most important of each of them be presented.
The text that describes figures 3 to 5 little can be appreciated in the maps, I suggest that authors can use tables.
The follow sentences correspond to discussion “Driven by factors such as economy, population development, and social construction, the landscape type of ecological space is more and more strongly disturbed by external factors, and the pattern tends to be fragmented and heterogeneous, resulting in a large reduction and fragmentation of forested and cultivated land in the northeastern river valley lowlands, the central low-hill plains, and the southeastern coastal area”.
The follow sentences, of 3.1.3section, correspond to methods “Referring to the relevant theoretical research results [15-16,36], the study area was divided into 0.5km×0.5km cell grids as evaluation units, and the comprehensive ecological risk index within each evaluation unit was calculated, and this was used as the ecological risk index value at the center point of the evaluation unit, which in turn yielded the spatial distribution of the ecological risk value in the study area from 1990 to 2020. The landscape ecological index of each cell grid in Pulandian District was calculated from equations (1) to (3). The spatial distribution of landscape ecological risk in the whole study area was obtained by using the Kriging interpolation method, and it was categorized into five eco-logical risk classes, such as high ecological risk area (>0.76], higher ecological risk area (0.58, 0.76], medium ecological risk area (0.4, 0.58], lower ecological risk area (0.22, 0.4], and low ecological risk area (0, 0.22]), by using the equidistant spacing method ( Figure 5).”
The follow sentences, of 3.1.3 section, correspond to discussion: “The degree of urbanization in this area is relatively high, and the types of land use are mainly construction land, arable land, and unutilized land, and the disturbance of ecology caused by human activities is strong, which results in the poor ecological connectivity and thus leads to the poor ability of ecosystems to resist disturbances. The lower ecological risk and low ecological risk zones are located in the northern part of the country, such as Tongyi and Anbo, where forested areas account for a large proportion of the area and the ecological environment is better.”
Report, in methods, the criteria for defining risk categories of figure 5.
Describe in methods ecological pinches, ecological barriers, and ecological obstacles.
Discussion
The interpretation of the results is insufficient, for example the discussion of optimization of ecological patterns. Also, it is recommended that the authors propose additional studies to be conducted to support their results and interpret the implications of their results for both urban planning as natural resource conservation.
Author Response
Dear Reviewers：
Thank you very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! We have tried our best to improve and made some changes in the manuscript.Please find my itemized responses in below.
Point 1:
Keywords
I suggest that authors use words other than those included in the title. The key words represent the content of your manuscript and be specific to your field or sub-field. Use different words from title will increase the number of people reading your manuscript, and likely lead to more citations.
Response 1:
Thank you very much for your advice. After discussion, we selected several new keywords for replacement such as Evaluation indicators, spatial pattern analysis, etc. While there are still a few keywords that are included in the title, but we think they are also representative, So we thought they might be worth preserving.
Keywords: Evaluation indicators; Analysis of spatial patterns; Ecological risk; Pulandian
Point 2:
Introduction
I suggest that the authors present a hypothesis based on their argument "relatively few studies on the construction of ecospatial networks from the ecological risk perspective" (page 3). For example, how much can the model be improved by implementing the ecological risk perspective. optimization of ecological patterns.
Response 2:
After careful consideration of your suggestion, we have added the following paragraph to the introduction to improve it.
Constructing an ecospatial network from the perspective of ecological risk can better identify and assess the risks to the ecological environment. This new ecological environment management approach organically integrates the relationship between the ecological environment and various aspects of human society and economic activities, which can more comprehensively identify and assess the risks of the ecological environment and provide a basis for formulating a more scientific and rational ecological environment management strategy.
Point 3:
Methods
Specify that Liaodong peninsula is in China (page 4, section 2.1). Include coordinates on maps.
Explain what the combination of entropy weight method and mean square deviation decision-making method.
Describe ecological service value, ecosystem biomass factor, landscape fragmentation Ci, landscape separation Ni, and landscape dominance Di
MSPA describe the acronym.
Include reference of Guidos Toolbox software
Response 3:
In accordance with your suggestion we have redrawn the map and marked the coordinates and designated the Liaodong Peninsula as being in China.
The explanation of the combination of entropy weight method and mean square deviation decision-making method. is as follows.
The description of ecological service value, ecosystem biomass factor, landscape fragmentation Ci, landscape separation Ni, and landscape dominance Di is as follows and has added the text and formulas to the manuscript
Issues relating to MSPA and Guidos Toolbox were dealt with accordingly
The entropy weight method and the mean square deviation method are used in combination to synthesize the respective advantages of the two methods and improve the accuracy and stability of evaluation and decision-making. Specifically, the entropy weight method can be used to calculate the weight of each indicator to reflect the degree of importance of each indicator in the comprehensive evaluation. Then, the mean square deviation method can be used to conduct a comprehensive evaluation of each sample to determine its final evaluation results. The comprehensive method using entropy weight method and mean square deviation method can fully utilize the respective advantages of the two methods. The entropy weight method can objectively determine the weight of each indicator, avoiding the influence of human factors on the evaluation results, and at the same time, it can comprehensively consider multiple factors to make decisions. The mean square deviation method can deal with continuous data, and has the advantages of easy to understand, simple calculation and stable effect. By combining the two methods, the accuracy and stability of evaluation and decision-making can be further improved.
The valuation of ecological services refers to the assessment and calculation of the ecological services provided by ecosystems. The ecological service value of ecosystems includes direct and indirect use values, as well as non-use values. Direct use value refers to the direct utilization of the material and energy provided by the ecosystem. Methods of ecological service valuation include the market method, shadow engineering method, cost and expenditure method, gain and loss method, and conditional value method. Evaluation of ecological service value can provide an important basis for the formulation of ecological protection policy and economic development planning. By evaluating the ecological service value of ecosystems, the value and role of ecosystems can be better recognized and ecological protection and sustainable development can be promoted.
Ecosystem biomass factor is the proportional relationship between organisms and biomass in an ecosystem. Biomass is the total mass of organisms in an ecosystem, including plants, animals, and microorganisms. The biomass factor helps us to understand the distribution and productivity of biomass in an ecosystem and thus assess the health and functioning of the ecosystem. In ecology, biomass factor is an important indicator that can be used to assess the productivity and species diversity of an ecosystem. Through the study of biomass factor, we can better understand the growth and reproduction capacity of organisms under different environmental conditions, and provide a scientific basis for the protection and management of ecosystems.
MSPA （Morphological Spatial Pattern Analysis）analysis is a method for morphospatial pattern analysis, which is used to identify the spatial topological relationship between the target image set and structural elements, and categorize the target image set into seven types: core, patch, pore, edge, bridging, loop, and feeder.MSPA is able to be used in a variety of application areas, such as landscape structural analysis, urban spatial distribution study, land use change detection, and ecosystem stability assessment.
Guidos Toolbox is a software for image processing that contains various general-purpose raster image processing functions. The software was developed by Guido Socher. It was first used as a graphical user interface for describing image objects and their shapes. Nowadays, Guidos Toolbox has evolved into a toolset containing a wide range of functions that can be used for tasks such as image segmentation, feature extraction, and morphological manipulation.In morphological spatial pattern analysis, Guidos Toolbox can be used to implement the MSPA analysis method, an image processing technique based on morphological methods for recognizing various shapes and structural patterns in an image. By using Guidos Toolbox, MSPA analysis can be easily performed and various features and attributes in the image can be extracted.
Point 4:
Results
I consider that section 3.1 corresponds to the inputs to perform the optimization of ecological patterns, so I suggest that it be included as an appendix. The description of this section is monotonous and distracts from the main topic, so I suggest that only the most important of each of them be presented.
The text that describes figures 3 to 5 little can be appreciated in the maps, I suggest that authors can use tables.
The follow sentences correspond to discussion “Driven by factors such as economy, population development, and social construction, the landscape type of ecological space is more and more strongly disturbed by external factors, and the pattern tends to be fragmented and heterogeneous, resulting in a large reduction and fragmentation of forested and cultivated land in the northeastern river valley lowlands, the central low-hill plains, and the southeastern coastal area”.
The follow sentences, of 3.1.3section, correspond to methods “Referring to the relevant theoretical research results [15-16,36], the study area was divided into 0.5km×0.5km cell grids as evaluation units, and the comprehensive ecological risk index within each evaluation unit was calculated, and this was used as the ecological risk index value at the center point of the evaluation unit, which in turn yielded the spatial distribution of the ecological risk value in the study area from 1990 to 2020. The landscape ecological index of each cell grid in Pulandian District was calculated from equations (1) to (3). The spatial distribution of landscape ecological risk in the whole study area was obtained by using the Kriging interpolation method, and it was categorized into five eco-logical risk classes, such as high ecological risk area (>0.76], higher ecological risk area (0.58, 0.76], medium ecological risk area (0.4, 0.58], lower ecological risk area (0.22, 0.4], and low ecological risk area (0, 0.22]), by using the equidistant spacing method ( Figure 5).”
The follow sentences, of 3.1.3 section, correspond to discussion: “The degree of urbanization in this area is relatively high, and the types of land use are mainly construction land, arable land, and unutilized land, and the disturbance of ecology caused by human activities is strong, which results in the poor ecological connectivity and thus leads to the poor ability of ecosystems to resist disturbances. The lower ecological risk and low ecological risk zones are located in the northern part of the country, such as Tongyi and Anbo, where forested areas account for a large proportion of the area and the ecological environment is better.”
Report, in methods, the criteria for defining risk categories of figure 5.
Describe in methods ecological pinches, ecological barriers, and ecological obstacles.
Response 4:
The problems in section 3.1 have been actively rectified in the manuscript.
Regarding Figures 3 through 5, we added Tables 4, 5, and 6 to the manuscript to facilitate a more visual representation of the data processing results
Definitions of risk categories are placed in the manuscript in section 2.3.2 through text and tables
Added descriptions of ecological pinches, ecological barriers and ecological obstacles to methods
2.3.2 Normalization of evaluation indicator values
Landscape ecological risk evaluation is a process of comprehensive evaluation of multiple indicators, and various types of indicators are involved in a wide range of process and take values with large difference intervals, while the scale between the indicators is inconsistent, and comparability is low, meaning that the comprehensive evaluation of these indicators cannot be directly performed. In this regard, this paper selected 14 indicators to grade and standardize the impact on the ecological environment of the study area, and the grading was divided into five levels (Table 2) to eliminate the error between the data of each indicator due to the inconsistency of the unit, with the aim of better evaluating the ecological risk of Pulandian District.
In the landscape ecological risk evaluation index, the larger the value, the greater the contribution to the landscape ecological risk of the region, the higher the level of low risk, the formula for the positive index is:
The larger some of the values in the landscape ecological risk assessment metrics are, the less they contribute to the landscape ecological risk of the region. The formula for the negative indicator is:
Where: Xi is the normalized value, xi is the original value of indicator i, xmax is the maximum value of the indicator, and xmin is the minimum value of the indicator.
Ecological barrier zones are key nodes that play an important role in connectivity between different ecological source plates. When ecological restoration measures are taken, the cumulative resistance value within the barrier area is reduced, the resistance value is reduced accordingly, and the area with the greatest reduction can be regarded as the ecological barrier point.
Point 5:
Discussion
The interpretation of the results is insufficient, for example the discussion of optimization of ecological patterns. Also, it is recommended that the authors propose additional studies to be
conducted to support their results and interpret the implications of their results for both urban planning as natural resource conservation.
Response 5:
Thank you for your suggestions, we have changed the conclusion section
Round 2
Reviewer 1 Report
For Response 7:
Not yet. In lines 60 and 66, why did the MCR model use the acronym directly in the first reference while instead using the full (defining abbreviations) form when mentioned the second time? This is completely the opposite of correct writing!
For Response 13:
Okay, but why is a '/' used to connect numbers and units in lines 180 to 183? Should be changed to a space.
For Response 16:
I have compared the manuscript versions before and after the revisions, and the authors did not summarize and rewrite the Conclusion chapter as they stated, or even just deleted the serial number to superficially adjust the structure. This is quite dishonest.
I hope the authors understand that the current Discussion and Conclusion chapters are not what qualified academic research articles should be.
Well, it seems that the authors did not really want to improve the quality of their manuscript, which is a pity.
None.
Author Response
Dear Reviewer,
We would like to express our sincere gratitude and admiration towards you. Your rigorous approach towards the review process has left a profound impression on us. Your criticisms and suggestions are constructive and have been extremely helpful in improving our paper.
We apologize for the errors that you have pointed out, and we have recognized these issues. We will immediately correct these mistakes and ensure that similar errors do not occur again.
Below, please find our response to this report.
Point 1:
For Response 7:
Not yet. In lines 60 and 66, why did the MCR model use the acronym directly in the first reference while instead using the full (defining abbreviations) form when mentioned the second time? This is completely the opposite of correct writing!
Response 1:
We greatly appreciate your feedback. We have corrected the error pointed out by you and checked other parts of the manuscript to prevent similar issues from happening again. Your comments and suggestions have been very helpful in improving the quality of our work.
Point 2:
For Response 13:
Okay, but why is a '/' used to connect numbers and units in lines 180 to 183? Should be changed to a space.
Response 2:
We appreciate your input. We apologize for our negligence and lack of knowledge, and the errors in the article have been corrected.
Point 3:
For Response 16:
I have compared the manuscript versions before and after the revisions, and the authors did not summarize and rewrite the Conclusion chapter as they stated, or even just deleted the serial number to superficially adjust the structure. This is quite dishonest.
I hope the authors understand that the current Discussion and Conclusion chapters are not what qualified academic research articles should be.
Response 3:
It may be due to technical reasons which caused the modified parts to not be reflected in the manuscript, we apologize for this. We have no intention of engaging in any deceptive behavior. This time, we have fully modified the Discussion section and replaced the Conclusion section as requested. We ensure that the previous error will not be repeated.
4.Discussion
4.1.Characterizing the evolution of ecospatial landscape types
From 1990 to 2020, the ecological space of Pulandian District, such as woodland, grassland, lake, beach land, etc., showed a wave-like trend in quantity, with a total increase of 51.71 km2, representing an increase of 6.8%. However, the area of beach land continuously decreased, with a decrease of 13.91%, which is 15.27% higher than the decrease in the area of farmland. The largest change in the area of a land use landscape type was the expansion of construction land, with an increase of 153.84 km2, or 86.59%; the land use type with the largest transfer to construction land was beach land, and the ecological space in the area near the construction land was more severely fragmented. The cultivated land area decreased the most, by 204.544 km2, with a decrease of 11.78% (Fig. 2). From the changes in ecological landscape types, it can be concluded that the total ecological space volume has increased over the past 30 years because the increase in woodland is much larger than the decrease in grassland, beach land, and lake area is generally seen to have increased, and the trend of the total ecological space volume is also related to the trend of the change in the area of woodland. Driven by factors such as the economy, population development, and social construction, the landscape type of ecological space has been increasingly disturbed by external factors, and the pattern tends to be fragmented and heterogeneous, resulting in a significant reduction and fragmentation of woodland and farmland in the northeast river valley lowlands, the central low-lying plains, and the southeast coastal area. This is strongly associated with the intensification of infrastructure development in the study area, which depletes natural resources and disregards long-term land planning.
4.2.Characterization of the evolution of ecological source areas
Comparative analysis of the spatial pattern of landscape morphology in the coastal county Pulandian District in four periods is provided in Figure 3. The area of the ecological core area in the region showed a wave-like trend of increasing, then decreasing and then increasing during the 30-year period, with an increase of 104.257 km2; the area of the fringe area demonstrated a growth trend of decreasing and then increasing, with an increase of 12.141 km2. Considering that the core area, as a large area of ecological patches, is constantly being encroached upon and fragmented during the process of urbanization, this will form more fringe zones, leading to an increase in the percentage of the area of fringe zones. This indicates that the continuous development of new urbanization, people demanding higher requirements for the living environment, and the implementation of a series of policies such as afforestation and the return of farmland to woodlands have contributed to the increase in the ecological core area in the study area. From the change in landscape selection pattern in Figure 3 and Table 5, it can be concluded that the percentage of the ecological core area decreased by 4.03% from 2000 to 2010, while its area increased by 3.56% during the 2010-2020 period. Meanwhile, the percentage of the bridging area decreased by 0.42% and the area of the fringe area increased by 12.141 km2 in 30 years, indicating a decreasing trend in ecological connectivity and a more fragmented regional landscape. The results of this study show that the area of the ecological core area tended to decrease as a result of the vigorous urban construction in Pulandian District after 2000. After 2010, ecological restoration in the main urban area was mostly carried out locally, which did not fundamentally alleviate the shrinkage of the ecological source area caused by urbanization, making it more difficult to maintain the ecological function of the region.
4.3.Characterization of spatial and temporal changes in ecological risk
From a time-dimension perspective, between 1990 and 2020, the proportion of high- and higher-risk areas first increased and then decreased, the proportion of medium- and lower-risk areas first decreased and then increased, and the proportion of low-risk areas first decreased, then increased, and then decreased again. The share of high- and higher-risk areas reached its lowest value, and the share of low-risk areas reached its highest value. Overall, during the period from 1990 to 2020, due to the acceleration of urbanization, the intensity of land use in Pulandian has been increasing, human activities have intervened to enhance land ecological risk, and the degree of land use ecological risk has been decreasing.
From the perspective of the spatial dimension, compared with 1990, the high-risk area in 2000 increased by two areas: Tiexi in the west and Daliujia in the southeast. The higher-risk areas are mainly located in Yangshufang and Tangjiafang in the southeast, Datan and Lianshan and Mopan in the center, and Siping and Shuangta in the north. The medium-risk zones are distributed in Taiping in the west and Chengzitan in the southeast, the southwest of Tongyi in the north, and Shabao in the center. The lower-risk zones are distributed in Xingtai in the center and Lejia in the north. The low-risk areas are mainly located in the coastal areas of Anbo in the north and Chengzitan in the southeast. In 2010, the high-risk areas were mainly located in Fengrong and Taiping in the west, and the higher-risk areas were located in Pikou and Yangshufang in the southeast, as well as Shuangta in the north and Mopan in the center. The medium-risk areas are mainly located in Lianshan and Datan in the center and Tongyi and Siping in the north. The lower-risk zones are distributed in Shabao in the center and Chengzitan in the southeast. The low-risk areas are located in Lejia and Anbo in the north. In 2020, the high-risk zones are mainly located in Tiexi and Fengrong in the west, and the higher-risk zones are located in Pikou, Yangshufang and Daliujia in the southeast. The medium-risk zones are mainly located in Lianshan, Xingtai and Datan in the center, and Siping in the north. The low-risk zones are mainly located in the north, such as Anbo and Siping.
In general, during the period from 1990 to 2020, high-risk areas are mainly distributed in the western region, such as Taiping and Fengrong, which belong to regions with rapid urbanization. Higher-risk areas are distributed in the south-east, north and central parts of the country. Medium-risk areas are distributed in the central part of the country, and lower-risk and low-risk areas are distributed in the central and northern parts of the country. In the later stages of the development process, attention should be paid to ecological security in high-risk areas, so as to safeguard ecological security in the whole region.
4.4.Characterization of the evolution of ecological resistance surfaces
From the perspective of the time dimension, the geography of Pulandian has not fundamentally changed from 1990 to 2020, and therefore the overall change in ecological resistance surfaces does not show a significant trend. However, this does not mean that the ecological environment of the region has not been affected in any way, but it may just have had a relatively small impact or slow change.
From the perspective of the spatial dimension, the ecological resistance surfaces in the area show obvious spatial distribution characteristics. High resistance surfaces are mainly concentrated in Xingtai and Lianshan in the center and Pikou, Yangshufang, and Tangjiafang in the southeast, which may exhibit high ecological resistance due to various factors such as topography, geomorphology, and human activities. In contrast, low resistance surfaces are mainly located in the northern areas such as Tongyi, Anbo, and Lejia, which may show lower ecological resistance due to better natural conditions and being farther away from the centers of human activities.
To sum up, areas with higher ecological resistance surfaces are more affected by economic development, increased urbanization and agricultural activities, which may mean that these areas have more severe environmental damage and are not suitable for ecological land expansion. Conversely, areas with lower ecological resistance surfaces are mainly distributed in the northern ecological reserve, which is more suitable for ecological land expansion because of its mountainous peaks and undulating terrain. This suggests that human activities have an obvious impact on the destruction of the ecological environment, and the protection and restoration of the ecological environment need to focus on those areas with higher ecological resistance.
4.5.Characterization of the evolution of ecological corridors
In the whole study area, important corridors are mainly distributed in the northern and southwestern regions, and general corridors are clustered in the southeastern region. Shorter important corridors are mainly located in the northern part of the study area, mainly connecting some ecological source sites in close proximity, and longer important corridors are mainly located in the southern and western parts of the study area. The year 1990 is a critical point when the number of important corridors is highest and habitat connectivity is best. This suggests that corridors in the region or ecosystem reached a relative peak in 1990. Starting from 2000, the number of important corridors began to decrease. This may be due to the fact that the core source areas began to shrink from the outside in, resulting in increased pressure on the corridors connecting to the source areas. This means that corridors may disconnect or lose their connectivity. By 2010, the number of important corridors had decreased but the total length had increased. This may be due to the erosion and loss of important ecological source sites resulting in fewer connecting corridors, especially those connecting north and south. This suggests that overall connectivity is decreasing despite the existence of fewer corridors. By 2020, the number of important corridors decreases again, but the total length remains the same. This may be due to increased urbanization and development, resulting in higher habitat resistance and the subsequent loss of some corridors that pass through this area. This suggests that human activities, such as urbanization and development, have a negative impact on corridor connectivity corridor connectivity.
4.6.Optimization of Ecological Space Network and Strategies
The ecological corridors in the northern part of Pulandian are closely connected and have good circulation, but the ecological corridors in the west and south are weakly connected. The coastal zone area in the southeast has few ecological source lands, and the cultivated land area of production land in the center accounts for a large proportion, which has not formed better connection with the ecological source lands in the north and southwest. The ecological source land in Pulandian District generally shows a state of aggregation in the north and scarcity in the south-central part, and there is the problem of insufficient ecological corridor connectivity. Based on the current situation of the study area, ecological source land, ecological corridor, and ecological node, ecological patch together constitute the ecological spatial optimization pattern of Pulandian District. We should strengthen the restoration and protection of corridors linking the western to southeastern and central to southeastern parts of the study area, in order to form a benign ecological network, and optimize Pulandian District. It can be made up of an ecological barrier, a coastal ecological zone, multiple ecological corridors, multiple ecological nodes and patches, including the northern mountainous forest, the salt field and coastal belt in the Yellow Sea inlet area in the southeast, the Biliu River ecological corridor, the Dasha River ecological corridor, the Laoma Mountain National Forest Park system in the Tongyi and Anbo areas, and the connecting lines consisting of Lianshan and Datan in the northwestern region and Tiesi, connecting lines consisting of Tangjiafang, Fengrong, and Daliujia in the central region and Xingtai and Mopan in the central region, and connecting lines consisting of the southwestern part of Siping and the northwestern part of Lejia. Central Anbo and other ecological corridors Pulandian National Forest Park, Laomao Mountain Scenic Area, Biliuhe Reservoir Liuda Reservoir Wusi Reservoir Daliangho Reservoir.
In addition, the protection and restoration of medium- and high-risk areas within the Pulandian District should begin with the ecological source buffer zone. Restoring ecological source buffer zones can greatly enhance landscape connectivity and reduce the resistance of ecological processes, thereby effectively reducing the ecological risk of the area. The construction land and farmland in the high-risk area have high resistance values, and the terrain in the buffer zone with a high resistance level is flat. Therefore, the rapid expansion of construction land and the blind occupation of farmland have seriously damaged the ecological environment. The stability of the ecosystem should be strengthened by encouraging local residents to carry out the protection and restoration of ecological land and returning farmland to forests, and raising the environmental awareness of residents. Ecological corridor protection and restoration focuses on the construction of biological migration corridors, building channels for exchanges between species and ecological environments to increase the circulation of the entire ecological environment and enhance the sustainability of the ecological environment.
5.Conclusions
In this study, we employed three different evaluation methods—the indicator-based method, the MSPA method, and a comprehensive evaluation method—to identify ecological source areas. We constructed ecological corridors using the MCR model and Linkage Mapper model. The ecological risk assessment provided guidance for optimizing the ecological spatial network and promoted an optimal allocation of ecological spatial elements, enhancing the level of ecological security.
Our research results showed that：
The ecological space in the Pulandian District of Dalian City from 1990 to 2020 shows a trend of increase-decrease-increase in terms of quantity. The main reason for the first increase is that the Pulandian District of Dalian City responded positively to the policy of returning farmland to forests and converted part of its cultivated land to forests, which led to an increase in the area of ecological land. The main reason for the decrease is the continuous expansion of urban and industrial land use and the pressure on the ecological environment caused by the increase in population and the expansion of production activities, resulting in a decrease in ecological space. Among them, the area of beach land is continuously decreasing, and it is also the ecological space landscape type that has been converted to construction land the most. The main reasons for the final increase are economic development and industrial restructuring, as well as the implementation of more ecological restoration and protection projects, which reduced the expansion of industrial and construction land and reduced the loss of ecological space.
From 1990 to 2020, the spatial variability of ecological risk was high in different periods, with the proportion of high- and higher-risk areas showing a trend of increase and then decrease, the proportion of medium and lower-risk areas showing a trend of decrease and then increase, and the low-risk areas showing a trend of decrease and then increase and then decrease. The changes were most pronounced in the western and central parts of the study area.
The contraction or even disappearance of the core ecological source areas in the study area due to disturbances in the economy, population development, and social construction during the period from 1990 to 2020. The number of corridors, the number of patches, the degree of loop-through, the point-line rate and the degree of connectivity in the study area after restoring the ecological source area based on the ecological risk assessment results have been increased to varying degrees.
Currently, many researchers are studying cities or urban clusters on a larger scale or focusing on ecological security evaluation and ecosystem-based regional planning. We believe that the ecological spatial network optimization based on ecological risk assessment at the county level not only reflects the ecological security situation of the studied area, but also provides direction for optimizing the ecological spatial network, and furthermore, provides theoretical basis for the construction of ecological environment in the studied area as well as for decision-making by other relevant departments within the county.
Reviewer 3 Report
The authors modified most of the reviewer's comments and significantly improved the quality of the contribution. Nevertheless, I recommend that the authors add to the contribution why they are actually presenting the contribution, on the basis of which research the contribution was created, and what the research questions and hypotheses were. Furthermore, I still lack specific research contributions in the paper, the conclusions are still too general.
These comments were already in the first review procedure and were not accepted. I believe that processing these comments can contribute even more to the quality of the post.
Author Response
Dear Reviewer,
We sincerely appreciate your professional expertise and discerning eye during the review process. Your thoughtful feedback has had a profound impact on our article, making it more accurate and complete. This feedback helped us to refine and improve our work. We are grateful for the time and effort you have devoted to the review, and we truly appreciate your dedication to maintaining the high quality of the published works.
Point 1:
I recommend that the authors add to the contribution why they are actually presenting the contribution, on the basis of which research the contribution was created, and what the research questions and hypotheses were. Furthermore, I still lack specific research contributions in the paper, the conclusions are still too general.
Response 1:
We sincerely appreciate your feedback and suggestions. We humbly ask if we have correctly understood your meaning, and we have carefully considered and made modifications based on your comments. We have made significant edits to the discussion and conclusion sections of the article. The modified portions are as follows.
4.Discussion
4.1.Characterizing the evolution of ecospatial landscape types
From 1990 to 2020, the ecological space of Pulandian District, such as woodland, grassland, lake, beach land, etc., showed a wave-like trend in quantity, with a total increase of 51.71 km2, representing an increase of 6.8%. However, the area of beach land continuously decreased, with a decrease of 13.91%, which is 15.27% higher than the decrease in the area of farmland. The largest change in the area of a land use landscape type was the expansion of construction land, with an increase of 153.84 km2, or 86.59%; the land use type with the largest transfer to construction land was beach land, and the ecological space in the area near the construction land was more severely fragmented. The cultivated land area decreased the most, by 204.544 km2, with a decrease of 11.78% (Fig. 2). From the changes in ecological landscape types, it can be concluded that the total ecological space volume has increased over the past 30 years because the increase in woodland is much larger than the decrease in grassland, beach land, and lake area is generally seen to have increased, and the trend of the total ecological space volume is also related to the trend of the change in the area of woodland. Driven by factors such as the economy, population development, and social construction, the landscape type of ecological space has been increasingly disturbed by external factors, and the pattern tends to be fragmented and heterogeneous, resulting in a significant reduction and fragmentation of woodland and farmland in the northeast river valley lowlands, the central low-lying plains, and the southeast coastal area. This is strongly associated with the intensification of infrastructure development in the study area, which depletes natural resources and disregards long-term land planning.
4.2.Characterization of the evolution of ecological source areas
Comparative analysis of the spatial pattern of landscape morphology in the coastal county Pulandian District in four periods is provided in Figure 3. The area of the ecological core area in the region showed a wave-like trend of increasing, then decreasing and then increasing during the 30-year period, with an increase of 104.257 km2; the area of the fringe area demonstrated a growth trend of decreasing and then increasing, with an increase of 12.141 km2. Considering that the core area, as a large area of ecological patches, is constantly being encroached upon and fragmented during the process of urbanization, this will form more fringe zones, leading to an increase in the percentage of the area of fringe zones. This indicates that the continuous development of new urbanization, people demanding higher requirements for the living environment, and the implementation of a series of policies such as afforestation and the return of farmland to woodlands have contributed to the increase in the ecological core area in the study area. From the change in landscape selection pattern in Figure 3 and Table 5, it can be concluded that the percentage of the ecological core area decreased by 4.03% from 2000 to 2010, while its area increased by 3.56% during the 2010-2020 period. Meanwhile, the percentage of the bridging area decreased by 0.42% and the area of the fringe area increased by 12.141 km2 in 30 years, indicating a decreasing trend in ecological connectivity and a more fragmented regional landscape. The results of this study show that the area of the ecological core area tended to decrease as a result of the vigorous urban construction in Pulandian District after 2000. After 2010, ecological restoration in the main urban area was mostly carried out locally, which did not fundamentally alleviate the shrinkage of the ecological source area caused by urbanization, making it more difficult to maintain the ecological function of the region.
4.3.Characterization of spatial and temporal changes in ecological risk
From a time-dimension perspective, between 1990 and 2020, the proportion of high- and higher-risk areas first increased and then decreased, the proportion of medium- and lower-risk areas first decreased and then increased, and the proportion of low-risk areas first decreased, then increased, and then decreased again. The share of high- and higher-risk areas reached its lowest value, and the share of low-risk areas reached its highest value. Overall, during the period from 1990 to 2020, due to the acceleration of urbanization, the intensity of land use in Pulandian has been increasing, human activities have intervened to enhance land ecological risk, and the degree of land use ecological risk has been decreasing.
From the perspective of the spatial dimension, compared with 1990, the high-risk area in 2000 increased by two areas: Tiexi in the west and Daliujia in the southeast. The higher-risk areas are mainly located in Yangshufang and Tangjiafang in the southeast, Datan and Lianshan and Mopan in the center, and Siping and Shuangta in the north. The medium-risk zones are distributed in Taiping in the west and Chengzitan in the southeast, the southwest of Tongyi in the north, and Shabao in the center. The lower-risk zones are distributed in Xingtai in the center and Lejia in the north. The low-risk areas are mainly located in the coastal areas of Anbo in the north and Chengzitan in the southeast. In 2010, the high-risk areas were mainly located in Fengrong and Taiping in the west, and the higher-risk areas were located in Pikou and Yangshufang in the southeast, as well as Shuangta in the north and Mopan in the center. The medium-risk areas are mainly located in Lianshan and Datan in the center and Tongyi and Siping in the north. The lower-risk zones are distributed in Shabao in the center and Chengzitan in the southeast. The low-risk areas are located in Lejia and Anbo in the north. In 2020, the high-risk zones are mainly located in Tiexi and Fengrong in the west, and the higher-risk zones are located in Pikou, Yangshufang and Daliujia in the southeast. The medium-risk zones are mainly located in Lianshan, Xingtai and Datan in the center, and Siping in the north. The low-risk zones are mainly located in the north, such as Anbo and Siping.
In general, during the period from 1990 to 2020, high-risk areas are mainly distributed in the western region, such as Taiping and Fengrong, which belong to regions with rapid urbanization. Higher-risk areas are distributed in the south-east, north and central parts of the country. Medium-risk areas are distributed in the central part of the country, and lower-risk and low-risk areas are distributed in the central and northern parts of the country. In the later stages of the development process, attention should be paid to ecological security in high-risk areas, so as to safeguard ecological security in the whole region.
4.4.Characterization of the evolution of ecological resistance surfaces
From the perspective of the time dimension, the geography of Pulandian has not fundamentally changed from 1990 to 2020, and therefore the overall change in ecological resistance surfaces does not show a significant trend. However, this does not mean that the ecological environment of the region has not been affected in any way, but it may just have had a relatively small impact or slow change.
From the perspective of the spatial dimension, the ecological resistance surfaces in the area show obvious spatial distribution characteristics. High resistance surfaces are mainly concentrated in Xingtai and Lianshan in the center and Pikou, Yangshufang, and Tangjiafang in the southeast, which may exhibit high ecological resistance due to various factors such as topography, geomorphology, and human activities. In contrast, low resistance surfaces are mainly located in the northern areas such as Tongyi, Anbo, and Lejia, which may show lower ecological resistance due to better natural conditions and being farther away from the centers of human activities.
To sum up, areas with higher ecological resistance surfaces are more affected by economic development, increased urbanization and agricultural activities, which may mean that these areas have more severe environmental damage and are not suitable for ecological land expansion. Conversely, areas with lower ecological resistance surfaces are mainly distributed in the northern ecological reserve, which is more suitable for ecological land expansion because of its mountainous peaks and undulating terrain. This suggests that human activities have an obvious impact on the destruction of the ecological environment, and the protection and restoration of the ecological environment need to focus on those areas with higher ecological resistance.
4.5.Characterization of the evolution of ecological corridors
In the whole study area, important corridors are mainly distributed in the northern and southwestern regions, and general corridors are clustered in the southeastern region. Shorter important corridors are mainly located in the northern part of the study area, mainly connecting some ecological source sites in close proximity, and longer important corridors are mainly located in the southern and western parts of the study area. The year 1990 is a critical point when the number of important corridors is highest and habitat connectivity is best. This suggests that corridors in the region or ecosystem reached a relative peak in 1990. Starting from 2000, the number of important corridors began to decrease. This may be due to the fact that the core source areas began to shrink from the outside in, resulting in increased pressure on the corridors connecting to the source areas. This means that corridors may disconnect or lose their connectivity. By 2010, the number of important corridors had decreased but the total length had increased. This may be due to the erosion and loss of important ecological source sites resulting in fewer connecting corridors, especially those connecting north and south. This suggests that overall connectivity is decreasing despite the existence of fewer corridors. By 2020, the number of important corridors decreases again, but the total length remains the same. This may be due to increased urbanization and development, resulting in higher habitat resistance and the subsequent loss of some corridors that pass through this area. This suggests that human activities, such as urbanization and development, have a negative impact on corridor connectivity corridor connectivity.
4.6.Optimization of Ecological Space Network and Strategies
The ecological corridors in the northern part of Pulandian are closely connected and have good circulation, but the ecological corridors in the west and south are weakly connected. The coastal zone area in the southeast has few ecological source lands, and the cultivated land area of production land in the center accounts for a large proportion, which has not formed better connection with the ecological source lands in the north and southwest. The ecological source land in Pulandian District generally shows a state of aggregation in the north and scarcity in the south-central part, and there is the problem of insufficient ecological corridor connectivity. Based on the current situation of the study area, ecological source land, ecological corridor, and ecological node, ecological patch together constitute the ecological spatial optimization pattern of Pulandian District. We should strengthen the restoration and protection of corridors linking the western to southeastern and central to southeastern parts of the study area, in order to form a benign ecological network, and optimize Pulandian District. It can be made up of an ecological barrier, a coastal ecological zone, multiple ecological corridors, multiple ecological nodes and patches, including the northern mountainous forest, the salt field and coastal belt in the Yellow Sea inlet area in the southeast, the Biliu River ecological corridor, the Dasha River ecological corridor, the Laoma Mountain National Forest Park system in the Tongyi and Anbo areas, and the connecting lines consisting of Lianshan and Datan in the northwestern region and Tiesi, connecting lines consisting of Tangjiafang, Fengrong, and Daliujia in the central region and Xingtai and Mopan in the central region, and connecting lines consisting of the southwestern part of Siping and the northwestern part of Lejia. Central Anbo and other ecological corridors Pulandian National Forest Park, Laomao Mountain Scenic Area, Biliuhe Reservoir Liuda Reservoir Wusi Reservoir Daliangho Reservoir.
In addition, the protection and restoration of medium- and high-risk areas within the Pulandian District should begin with the ecological source buffer zone. Restoring ecological source buffer zones can greatly enhance landscape connectivity and reduce the resistance of ecological processes, thereby effectively reducing the ecological risk of the area. The construction land and farmland in the high-risk area have high resistance values, and the terrain in the buffer zone with a high resistance level is flat. Therefore, the rapid expansion of construction land and the blind occupation of farmland have seriously damaged the ecological environment. The stability of the ecosystem should be strengthened by encouraging local residents to carry out the protection and restoration of ecological land and returning farmland to forests, and raising the environmental awareness of residents. Ecological corridor protection and restoration focuses on the construction of biological migration corridors, building channels for exchanges between species and ecological environments to increase the circulation of the entire ecological environment and enhance the sustainability of the ecological environment.
5.Conclusions
In this study, we employed three different evaluation methods—the indicator-based method, the MSPA method, and a comprehensive evaluation method—to identify ecological source areas. We constructed ecological corridors using the MCR model and Linkage Mapper model. The ecological risk assessment provided guidance for optimizing the ecological spatial network and promoted an optimal allocation of ecological spatial elements, enhancing the level of ecological security.
Our research results showed that：
The ecological space in the Pulandian District of Dalian City from 1990 to 2020 shows a trend of increase-decrease-increase in terms of quantity. The main reason for the first increase is that the Pulandian District of Dalian City responded positively to the policy of returning farmland to forests and converted part of its cultivated land to forests, which led to an increase in the area of ecological land. The main reason for the decrease is the continuous expansion of urban and industrial land use and the pressure on the ecological environment caused by the increase in population and the expansion of production activities, resulting in a decrease in ecological space. Among them, the area of beach land is continuously decreasing, and it is also the ecological space landscape type that has been converted to construction land the most. The main reasons for the final increase are economic development and industrial restructuring, as well as the implementation of more ecological restoration and protection projects, which reduced the expansion of industrial and construction land and reduced the loss of ecological space.
From 1990 to 2020, the spatial variability of ecological risk was high in different periods, with the proportion of high- and higher-risk areas showing a trend of increase and then decrease, the proportion of medium and lower-risk areas showing a trend of decrease and then increase, and the low-risk areas showing a trend of decrease and then increase and then decrease. The changes were most pronounced in the western and central parts of the study area.
The contraction or even disappearance of the core ecological source areas in the study area due to disturbances in the economy, population development, and social construction during the period from 1990 to 2020. The number of corridors, the number of patches, the degree of loop-through, the point-line rate and the degree of connectivity in the study area after restoring the ecological source area based on the ecological risk assessment results have been increased to varying degrees.
Currently, many researchers are studying cities or urban clusters on a larger scale or focusing on ecological security evaluation and ecosystem-based regional planning. We believe that the ecological spatial network optimization based on ecological risk assessment at the county level not only reflects the ecological security situation of the studied area, but also provides direction for optimizing the ecological spatial network, and furthermore, provides theoretical basis for the construction of ecological environment in the studied area as well as for decision-making by other relevant departments within the county.
Reviewer 4 Report
The authors changed the keywords, included a hypothesis in introduction, expanded the description of methods, removed the interpretation of their data in methods section, and expanded the discussion, which improved the quality of the manuscript.
Author Response
Dear Reviewer,
We would like to express our sincere gratitude for your valuable feedback and insights during the review process. Your expertise and critical analysis have been invaluable to us in improving our work.
We appreciate the time and effort you have devoted to reviewing our paper, and we are grateful for your constructive feedback and suggestions. Your input has helped us to carefully review our work and make necessary improvements. Your feedback has been instrumental in enhancing the quality of our paper.
Thank you again for your help and support.
Round 3
Reviewer 1 Report
This manuscript can be accepted for publication in Sustainability after the Ten-segment line element has been correctly added to the China map in Figure 1 to show the complete China region.
No.
Author Response
Point 1:
This manuscript can be accepted for publication in Sustainability after the Ten-segment line element has been correctly added to the China map in Figure 1 to show the complete China region.
Response 1:
Thank you very much for your feedback. We have made the suggested change to the figure in the article. The map now correctly shows the complete China region. Your input has been extremely helpful.
