Land-Use Transformation and Landscape Ecological Risk Assessment in the Three Gorges Reservoir Region Based on the “Production–Living–Ecological Space” Perspective
Round 1
Reviewer 1 Report
The article explores the landscape ecological risk assessment using statistics on the example of Three Gorges Reservoir Region. Though description of land use change is not innovative the study of regional and local situations should be continued for comparisons and universal knowledge formation.
This paper is well structured. There are some minor defects to be corrected:
- explain the origin of ecological environment quality index (lines 146-147)
- correct the typos: in word “according” line 170; lowercase letter in line 19; , there is Figure 7 – it should be Figure 5 in line 294
- improve legibility of graphics and legibility of descriptions on graphics (Figure 1,2,3,5)
- lines 330-331 are not clear in the context of article content. Is it connected with statements in point 5 of Discussion?
Author Response
Response to Reviewer 1 Comments
Point 1: Explain the origin of ecological environment quality index (lines 146-147).
Response 1: Thanks for your suggestions. We have added the origin of ecological environment qualty index: “Calculated the average area of land-use category, used the weighting method, the ecological environment quality index of the PLE-space land type was also assigned (Table 1) ” .
Point 2: Correct the typos: in word “according” line 170; lowercase letter in line 19; there is Figure 7 – it should be Figure 5 in line 294.
Response 2: Thanks for your suggestions. We have corrected the typos in line 170 and 294. But we did not find the error in lowercase letter in line 19. Please point this out to us, thank you!
Point 3: Improve legibility of graphics and legibility of descriptions on graphics (Figure 1,2,3,5).
Response 3: Thanks for your suggestions. We have added the content of the legend and improved the image pixels to improve legibility of Figure 1,2,3,5.
Point 4: Lines 330-331 are not clear in the context of article content. Is it connected with statements in point 5 of Discussion?
Response 4: Thanks for your suggestions. This statement is unconnected with the point 5 of Discussion. It intended to state that the grid should be an evaluation unit rather than a certain kind of landscape. We didn’t make it clear, so sorry. We have revise these lines as “The paper taken the 6km × 6km grid as the evaluation unit, evaluated changes in the TGRR in the past 20 years by constructing the LER model from the perspective of landscape ecology and PLE-space”.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The article develops a case study with a correct scientific method. Its content is adjusted to the themes of Land journal.
These minor revisions must be addressed for publication:
- On page 2 cite the authors by their last name and not by their first name as is done with Emily Hart Hayes, Fu Bojie and Chen Liding, and Zeng Hui et al. On that same page an author is cited as “Forbes V E” instead of “Forbes”.
- In the figures, the source of the data must always be added and specify if it is the authors' own elaboration. The source of all figures must be added.
- In the “Discussion” section it is not correct to number the paragraphs. Delete that number.
- The paragraphs now numbered as (4) and (5) of the 'Discussion' section should be transferred, without numbering, to the 'Conclusion' section. There the authors point out the limitations of the work and future research. These issues should be in the conclusions and not in the discussion.
Likewise, the reviewer makes the following recommendations to the authors:
- Shorten the title. It is currently too long and not very understandable.
- There is an abuse in the use of acronyms. This makes it difficult for the reader to understand the text in sentences such as “The transformation from APS to FES and URLS had a higher contribution rate to LER compared to other events”.
Author Response
Response to Reviewer 2 Comments
Point 1: On page 2 cite the authors by their last name and not by their first name as is done with Emily Hart Hayes, Fu Bojie and Chen Liding, and Zeng Hui et al. On that same page an author is cited as “Forbes V E” instead of “Forbes”.
Response 1: Thank you for your suggestions. We have corrected these names.
Point 2: In the figures, the source of the data must always be added and specify if it is the authors' own elaboration. The source of all figures must be added.
Response 2: Thank you for your suggestions. According to your comments, we have added the source of the data below all the figures.
Point 3: In the “Discussion” section it is not correct to number the paragraphs. Delete that number.
Response 3: Thank you for your suggestions. According to your comments, we have deleted the number.
Point 4: The paragraphs now numbered as (4) and (5) of the 'Discussion' section should be transferred, without numbering, to the 'Conclusion' section. There the authors point out the limitations of the work and future research. These issues should be in the conclusions and not in the discussion.
Response 4: Thank you for your suggestions. According to your comments, we have transferred the paragraphs now numbered as (4) and (5) of the ‘Discussion’ section to the ‘Conclusion’ section, without numbering.
Point 5: Shorten the title. It is currently too long and not very understandable.
Response 5: Thank you for your suggestions. We have changed the title to “Land Use Transformation and Landscape ecological risk assessment in Three Gorges Reservoir Region Based on the View of ‘Production-Living-Ecological Space’”. But we’re not sure if such a modification meets your requirements, please give us more advic. Thanks!
Point 6: There is an abuse in the use of acronyms. This makes it difficult for the reader to understand the text in sentences such as “The transformation from APS to FES and URLS had a higher contribution rate to LER compared to other events”.
Response 6: Thank you for your suggestions. According to your comments, we have changed some acronyms to full names for reader to understand the text in sentences. Such as “The transformation from agricultural production space to forestland ecological space and urban/rural living space had a higher contribution rate to LER compared to other events”.
Author Response File: Author Response.docx
Reviewer 3 Report
Spatio-Temporal Pattern of the Production-Living-Ecological Space and its landscape ecological risk assessment in an Ecological Fragile Area
The title is very attractive, but not fit with the contents and findings of the draft.
Abstract: The objective of the paper is not clear. The abstract starting with two sentences (I can agree with these sentences according to the World region), and then jump to methods. This look like as a report thana scientific paper. In fact, the methods describe there can not study the fragility of the sustainability of the areas, and just describe the land use change across 20 years. The results are not sound.
Introduction: The same weakness observed in the abstract are found in the introduction. It is clear the importance of the study area, however, the title contents were not included (as I expected) in the Introduction. In fact, there is more “methods” in the text than introduction. The introduction must present a problem, and the state of art of a new knowledge that the authors want to contribute to Science. This is look like a technical review. The objective is absent, and I suggest to clarify though questions or hypothesis, what the authors want to do.
Methods: To achieve the title contents, the authors must to combine land cover changes with field data taking metrics. In my perspective, the methods are poorly presented and not well connected to the main topics? A lack of any kind of statistics were found.
Results and conclusions are relevant for the studied basins, and no new knowledge was presented.
Author Response
Response to Reviewer 3 Comments
Point 1: Abstract: The objective of the paper is not clear. The abstract starting with two sentences (I can agree with these sentences according to the World region), and then jump to methods. This look like as a report thana scientific paper. In fact, the methods describe there can not study the fragility of the sustainability of the areas, and just describe the land use change across 20 years. The results are not sound.
Response 1: Thank you for your suggestions. We have revised the title as "Land Use Transformation and Landscape ecological risk assessment in Three Gorges Reservoir Region Based on the View of ‘Production-Living-Ecological Space’” . We take the Three Gorges Reservoir Region as the study area. This area is an important ecological barrier area in the Yangtze River basin in China, and it’s ecological environment is very fragil. The objective of this paper is to explore the relationship between the spatial type conversion of "Production-Living-Ecological" and the landscape ecological risk. So in the choice of methods, we constructed the land use classification system from the perspective of the “production-living-ecological” space (PLE-space). We used the land use transfer matrix to analyse the spatial evolution of the PLE-space. Then, combined the landscape disturbance index (Ei) and the landscape vulnerability index (Vi) that affect the stability of the regional ecosystem to build the landscape ecological risk (LER) assessment model. This model is used to assessment the landscape ecological risk in the study area. The spatial autocorrelation analysis is used to analyse the spatial and temporal changes of LER from 2000 to 2020. The ecological contribution rate of land use transfer is used to analyse the impact of the land use transformation of PLE-space on the ecological risk of the landscape. Above is our explanation, We are not sure if it is clear. Please give us more advice, thanks a lot.
Point 2: Introduction: The same weakness observed in the abstract are found in the introduction. It is clear the importance of the study area, however, the title contents were not included (as I expected) in the Introduction. In fact, there is more “methods” in the text than introduction. The introduction must present a problem, and the state of art of a new knowledge that the authors want to contribute to Science. This is look like a technical review. The objective is absent, and I suggest to clarify though questions or hypothesis, what the authors want to do.
Response 2: Thanks for your suggestions. According to your comments, in the revised version, we have added some contents in the introduction.
Point 3: Methods: To achieve the title contents, the authors must to combine land cover changes with field data taking metrics. In my perspective, the methods are poorly presented and not well connected to the main topics? A lack of any kind of statistics were found.
Response 3: Thank you for your suggestions. According to your comments, perhaps our title is ambiguous. So that in order to understand, we have adjusted the title. However, we are not sure whether the adjusted title still has the question you said. Because we don't quite understand what you mean by “combining land cover changes with field data taking metrics”. In the Response 1, we explained the objective of this paper is to explore the relationship between the spatial type conversion of "Production-Living-Ecological" and the landscape ecological risk. So that we think that these methods can solve this problem. In addition, we mainly discuss the impact of land use transformation on regional landscape ecological risk from the view of PLE-space. Therefore, land use data are mainly used, and no other statistics are involved. The question you said will be the direction of our improvement in the future. We will build on this paper, combine land cover changes with statistics and field data taking metrics, to analyse the fragility of the sustainability of the area.
Point 4: Results and conclusions are relevant for the studied basins, and no new knowledge was presented.
Response 4: Thank you for your suggestions. Considering the impact of land use transformation on landscape ecological risk. Therefore, the control of regional land-use transformation, the rational planning of land use, and ecological environment protection should be strengthened. In the revised version, We reviewed the literature. From the perspective of building a low-carbon territorial space planning, we add a paragraph “Adhering to the principle of ‘ecology priority’. The concept of ‘dual carbon’ will be fully integrated into the territorial space planning, and play the overall leading role of planning in low-carbon space governance. Building a scientific and reasonable low-carbon territorial spatial pattern, limit territorial space development under the framework of ‘conditional planning’. Comprehensively optimize human-land relations, and promote the low-carbon operation of the ‘economic-social-ecological’ composite system”.
Author Response File: Author Response.docx
Reviewer 4 Report
Dear authors, I find your manuscript a very interesting perspective on the topic of study, and it fits perfectly with Land's thematic lines. Let me just make a few small suggestions:
1.- Even if you specify the meaning of the acronyms in the abstract of the manuscript, please also specify them the first time they appear in the main text.
2.- When naming particular works throughout the manuscript, they only talk about the authors. Although it is true that they always specify the bibliographical reference at the end, I recommend adding the year of publication after the author's name.
3.- Study area: I consider the detail of the location of the study area provided to be excessive. Instead, it is necessary to provide a detailed climatic, edaphological and geological characterisation of the area.
4.- Line 158: I recommend that you remove the link in the manuscript. This type of information should be placed like any other reference. The link should not appear directly in the manuscript.
5.- Lines 297-307: this information should follow figure 2 and not precede it.
6.- Discussion: I recommend that in the discussion you add information on the main limitations you consider your study to have, as well as future lines of research that can be carried out on the basis of the research base you have generated.
Kind regards,
Author Response
Point 1: Even if you specify the meaning of the acronyms in the abstract of the manuscript, please also specify them the first time they appear in the main text.
Response 1: According to your comments, we have added the meaning of the acronyms in the main text.
Point 2: When naming particular works throughout the manuscript, they only talk about the authors. Although it is true that they always specify the bibliographical reference at the end, I recommend adding the year of publication after the author's name.
Response 2: Thank you for your suggestions. According to your comments, we have added the year of publication after the author’s name.
Point 3: Study area: I consider the detail of the location of the study area provided to be excessive. Instead, it is necessary to provide a detailed climatic, edaphological and geological characterisation of the area.
Response 3: Thank you for your suggestions. According to your comments, The Study area that we revised as follow:
“The TGRR is located in southwestern China (105°49′-111°39′E, 28°31′-31°43′N) across the mountain valleys in central Hubei and the ridge and valley belt in eastern Sichuan, separated by the Daba Mountains in the north and the Sichuan-Hubei Plateau in the south. It involves 22 districts and counties under the jurisdiction of Chongqing and 4 districts and counties in Hubei Province, and has a total area of 57,543 km2 (Figure 1). The area has a subtropical humid climate and is mainly mountainous and hilly, with large topographic undulations. The forest coverage rate is about 48.2%. The soil types are mainly purple soil, lime soil, yellow soil and rice soil. With the increase of the water storage level during the construction of the Three Gorges Project, the soil erosion in the study area was serious. A large number of forest ecosystems were destroyed and a large number of sudden geological disasters were caused. It is an important part of the Economic Zone in the Upper Reaches of the Yangtze River and an ecological environmental barrier in the Middle and Lower Reaches of the Yangtze River. The rapid deterioration of the ecological environment has made the Three Gorges Reservoir area become one of the main ecologically fragile areas in the upper reaches of the Yangtze River.”
Point 4: Line 158: I recommend that you remove the link in the manuscript. This type of information should be placed like any other reference. The link should not appear directly in the manuscript.
Response 4: Thank you for your suggestions. I’m so sorry that we haven’t found “the link” in Line 158. We guess whether “the link” you said is the data source below the Figure’s name. We have deleted this data source.
Point 5: Lines 297-307: this information should follow figure 2 and not precede it.
Response 5: Thank you for your suggestions. I’m so sorry that we also haven’t found this information. We have revised the format for the references in the main text.
Point 6: Discussion: I recommend that in the discussion you add information on the main limitations you consider your study to have, as well as future lines of research that can be carried out on the basis of the research base you have generated.
Response 6: Thank you for your suggestions. According to your comments, our revised discussion is as follows:
“Based on existing studies[28-30,34], through PLE-space land use change and landscape pattern interaction research, the connection between these can be better analyzed at the macro level. The paper constructed the land use classification system from the perspective of the PLE-space. Used the land use transfer matrix to analyse the spatial evolution of the PLE-space. Taken the 6km×6km grid as the evaluation unit. Refered the existing researches[24,25,31-33,36-40], builded the LER assessment model and used the spatial autocorrelation analysis to analyse the spatiotemporal distribution characteristics of LER in the study area in the past 20 years. The ecological environment of the TGRR has been improved by the protection policies in recent years, but in general, the ecological environment is very fragile. Therefore, it is necessary to make the LER assessment for this area. Combined with the LER analysis in the TGRR, the following suggestions are put forward. Firstly, for medium and high-grade ecological risk areas. Attach importance to the impact of urban construction and the increase of industries along the river on the ecological risks on both sides of the Yangtze River. Reduce anthropogenic disturbance of high vulnerable landscape types such as waters. Strengthen wetland protection to reduce the risk of soil erosion in the TGRR. Secondly, for low-grade ecological risk areas. Environmental governance should be strengthened, Establish an ecological buffer zone. Reduce the possibility of forest land and grassland degradation and prevent land desertification. In the future protection, the TGRR should respect the integrity and heterogeneity of the landscape, and respect the self-restoration of nature.
Changes in the PLE-space influence changes in the landscape pattern of the TGRR, which in turn affects the ecological risk of the region. In this paper, we tried to use the ecological contribution rate of land-use transformation[43] and made a preliminary exploration of the strength of the PLE-space land-use types on the improvement and deterioration of the ecological environment. The results indicated that the changes in regional LER are associated with the transformation of the PLE land-use function type. Therefore, the control of regional land-use transformation, the rational planning of land use, and ecological environment protection should be strengthened. Implement the system of paid occupation of ecological land and the system of ecological space use control. Comprehensively improve the ecological environment governance and protection level in the TGRR. The paper provided a reference for land planning, sustainable development, and ecological civilization construction in ecologically fragile areas. Adhering to the principle of "ecology priority". Under the background of the integration of "dual carbon" goals and "multi-plan". The concept of "dual carbon" will be fully integrated into the territorial space planning, and play the overall leading role of planning in low-carbon space governance. Building a scientific and reasonable low-carbon territorial spatial pattern, limit territorial space development under the framework of "conditional planning". Comprehensively optimize human-land relations, and promote the low-carbon operation of the "economic-social-ecological" composite system[44].
It should be pointed out that the methods and ideas of this study need to be improved:
(1) The paper was relied too much on the present situation of land-use function. However, the changes in factors such as precipitation, topography, and soil organic matter content, as well as changes in economic, social, policy, and demographic factors all affect changes in the PLE-space. The in-depth analysis of various factors in the human and land system is very promising to reveal the land use change and landscape pattern problems more deeply. Therefore, in future studies, it is necessary to further evaluate and predict the evolution of PLE-space from multiple natural, social, and economic perspectives.
(2) The calculation methods and ecological significance of the parameters in the LER model were further elucidated in this paper by analysing a large number of researches. But the LER assessment is a complex process that requires considering multiple uncertainties. These factors determine the comprehensive evaluation results. In the LER assessment of the TGRR, the method and process need to be further improved.
(3) It remained to be further analyzed in how to make the ecological environment index of different PLE-space land use types more in line with the objective reality.”
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report
The draft not greatly changed compared to the first version.
Author Response
Point : The draft not greatly changed compared to the first version.
Response : Thank you for your suggestions. In the first round of amendments, we have made the modifications according to your opinion. Perhaps we did not understand your comments so clearly that our revision did not meet your requirements. Therefore, in this round of revision, we will respond to the four questions you raised in the first round. The details are as follows:
Point 1: Abstract: The objective of the paper is not clear. The abstract starting with two sentences (I can agree with these sentences according to the World region), and then jump to methods. This look like as a report thana scientific paper. In fact, the methods describe there can not study the fragility of the sustainability of the areas, and just describe the land use change across 20 years. The results are not sound.
Response 1: The objective of this paper is to explore the relationship between the spatial type conversion of "Production-Living-Ecological" and the landscape ecological risk. To make the purpose of the article more clear, we revised the title: “Land Use Transformation and Landscape ecological risk assessment in Three Gorges Reservoir Region Based on the View of ‘Production-Living-Ecological Space”. About the methods that we choossed: (1) Based on existing studies[1-3], we constructed the land use classification system from the perspective of the “production-living-ecological” space (PLE-space). (2) Based on existing studies[4], we refered to used the land use transfer matrix to analyse the spatial evolution of the PLE-space. (3) Landscape vulnerability analysis is only a part of the landscape ecological risk assessment, and we aimed to evaluate the landscape ecological risk in the study area. We combined the landscape disturbance index (Ei) and the landscape vulnerability index (Vi) that affect the stability of the regional ecosystem to build the landscape ecological risk (LER) assessment model. Based on existing studies[5-11], this model has been used by many scholars. So that We used this model to assessment the landscape ecological risk in the study area. (4) Based on existing studies[12,13], the spatial autocorrelation analysis is used to analyse the spatial and temporal changes of LER from 2000 to 2020. (5) Based on existing studies[14], we used the ecological contribution rate of land use transfer to analyse the impact of the land use transformation of PLE-space on the ecological risk of the landscape.
References
[1] Li X W, Fang C L, Huang J C, et al. The urban land use transformations and associated effects on eco-environment in northwest China arid region: A case study in Hexi Region, Gansu Province. Quaternary Sciences,2003, 23(3): 280-290.
[2] Cui J, Zang S Y. Regional disparities of land use changes and their eco-environmental effects in Harbin- Daqing- Qiqihar Industrial Corridor. Geographical Research,2013,32(5): 848-856.
[3] Yang Q K, Duan X J, Wang L, et al. Land Use Transformation Based on Ecological-production-living Spaces and Associated Eco-environment Effects:A Case Study in the Yangtze River Delta[J]. Scientia Geographica Sinica, 2018, 38(1): 97–106.
[4] Dong J J, Zhang Q, Niu J M. Changes of Land Use and Its Effects on Landscape Pattern and Environment in Hohhot[J]. Journal of Inner Mongolia University, 2008, 39(4): 417-424.
[5] Zhao Y, Luo Z J, Li Y T, et al. Study of the spatial-temporal variation of landscape ecological risk in the upper reaches of the Ganjiang River Basin based on the "PLE-space"[J]. Acta Geographica Sinica, 2019, 39(13): 4676–4686.
[6] Wang Y X, Liu S K, Lu R C, et al. Landscape Ecological Risk Assessment and Terrain Gradient Analysis of Guangxi's Border Areas in the Past 40 Years from the "Production-Living-Ecological" Space[J]. Journal of Ecology and Rural Environment, 2021, 37(12): 1586–1595.
[7] Wang, B., Ding, M., Li, S., Liu, L., Ai, J. Assessment of landscape ecological risk for a cross-border basin: a case study of the Koshi River Basin, central Himalayas. Ecol. Indicat. 2020, 117.
[8] Chen, J., Dong, B., Li, H., Zhang, S., Peng, L., Fang, L., Zhang, C., Li, S. Study on landscape ecological risk assessment of Hooded Crane breeding and overwintering habitat. Environ. Res. 2020, 187, 109649.
[9] Liu X Z, Li X S, Jiang D M. Landscape pattern identification and ecological risk assessment using land-use change in the Yellow River Basin[J]. Transactions of the Chinese Society of Agricultural Engineering, 2021, 37(4): 265-274.
[10] Chen D K, Shi L Y. The Landscape Ecological Risk Assessment and Prediction for Xiong'an New Area Based on Land Use Change[J]. Ecological Economy, 2021, 37(11): 224–229.
[11] Liu Y X, Wang Y L, Peng J, et al. Urban landscape ecological risk assessment based on the 3D framework of adaptive cycle[J]. Acta Ecologica Sinica, 2015, 70(7): 1052–1067.
[12] Yang Y X, Wang X, Meng D, et al. Test Method of Cultivated Land Grading Index Based on Spatial Autocorrelation[J]. Transactions of the Chinese Society for Agricultural Machinery, 2016, 47(5): 328–335.
[13] Liu S L, Hou X Y, Yin Y J, et al. Research progress on landscape ecological networks. Acta Ecologica Sinica, 2017, 37(12): 3947- 3956.
[14] Oliver M A, Webster R. A tutorial guide to geostatistics: Computing and modelling variograms and kriging[J]. Catena, 2014,113(2): 56-69.
Point 2: Introduction: The same weakness observed in the abstract are found in the introduction. It is clear the importance of the study area, however, the title contents were not included (as I expected) in the Introduction. In fact, there is more “methods” in the text than introduction. The introduction must present a problem, and the state of art of a new knowledge that the authors want to contribute to Science. This is look like a technical review. The objective is absent, and I suggest to clarify though questions or hypothesis, what the authors want to do.
Response 2: In the introduction, we added the relevant content about the importance of the study area and what we want to do: “Land use transformation refers to the change of regional land use form due to the influence of social and economic developmen. It is mainly reflected in the change of the function of the PLE-space. Therefore, the ecological risk problem caused by the transformation of land use is essentially caused by the imbalance of the PLE-space. Based on the leading function of land use, combining the spatial evolution of PLE-space with the transformation of land use is a new entry point to solve the coordinated development problem of PLE-space, and promote the regional sustainable development. It is of great significance to clarify the spatial evolution process of PLE-space and landscape ecological risks under the background of rapid social and economic developmen for optimizing the territorial spatial layout and sustainable development of the Three Gorges Reservoir area. In order to explore the relationship between the spatial type conversion of "Production-Living-Ecological" and the landscape ecological risk. Most of the studies have focused on a single land-use type, and few studies have been conducted to analyse LER from a PLE perspective[15,16]. Moreover, there is a lack of related studies with grids as units.” Therefore, from the perspective of PLE-space, this paper discusses the impact of the land use transformation to the ecological risk in the Three Gorges Reservoir area in the past 20 years. It provides reference for landscape ecological risk assessment, land sustainable use and territorial spatial layout optimization within the scope of relevant water conservancy and reservoir projects at home and abroad.
References
[15] Zhao Y, Luo Z J, Li Y T, et al. Study of the spatial-temporal variation of landscape ecological risk in the upper reaches of the Ganjiang River Basin based on the "PLE-space"[J]. Acta Geographica Sinica, 2019, 39(13): 4676–4686.
[16] Wang Y X, Liu S K, Lu R C, et al. Landscape Ecological Risk Assessment and Terrain Gradient Analysis of Guangxi's Border Areas in the Past 40 Years from the "Production-Living-Ecological" Space[J]. Journal of Ecology and Rural Environment, 2021, 37(12): 1586–1595.
Point 3: Methods: To achieve the title contents, the authors must to combine land cover changes with field data taking metrics. In my perspective, the methods are poorly presented and not well connected to the main topics? A lack of any kind of statistics were found.
Response 3: The methods that we used in this paper, were refered to the existing studies[1-14]. Regarding the choice of methods, we have illustrated this in the response 1. About the data that we used in our paper, refered to the existing studies[17-19], we used the land cover data that were derived from Globeland30's global surface cover database (http://www.globallandcover.com) , include 3 periods: 2000, 2010, and 2020. Combined with land use transfer matrix, landscape ecological risk (LER) assessment model, spatial autocorrelation analysis and the ecological contribution rate of land use transfer. From the perspective of PLE-space, this paper discusses the impact of the land use transformation to the ecological risk in the Three Gorges Reservoir area in the past 20 years. According to the existing researches[1-14], the above methods does not require additional field observation data.
References
[17] Zeng C, He J, He Q, et al. Assessment of Land Use Pattern and Landscape Ecological Risk in the Chengdu-Chongqing Economic Circle, Southwestern China. Land, 2022, 11, 659.
[18] Luo Z, Zeng J. Spatial growth simulation of land use in Tianjin from the perspective of resource and environmental protection. Geogr. Res. 2022, 41, 341–357.
[19] Hu J, Chen J, Peng S. Hot-spot Analysis of GlobeLand30 Data Studying. Remote Sens. Inf. 2018, 33, 1–7.
Point 4: Results and conclusions are relevant for the studied basins, and no new knowledge was presented.
Response 4: Thank you for your suggestions. According to your comments, our revised discussion is as follows:
Based on existing studies[1-4], through PLE-space land use change and landscape pattern interaction research, the connection between these can be better analyzed at the macro level. The paper constructed the land use classification system from the perspective of the PLE-space. Used the land use transfer matrix to analyse the spatial evolution of the PLE-space. However changes in factors such as precipitation, topography, and soil organic matter content, as well as changes in economic, social, policy, and demographic factors all affect changes in the PLE-space. The in-depth analysis of various factors in the human and land system is very promising to reveal the land use change and landscape pattern problems more deeply. Therefore, in future studies, it is necessary to further evaluate and predict the evolution of PLE-space from multiple natural, social, and economic perspectives.
The paper taken the 6km×6km grid as the evaluation unit. Refered the existing researches[5-11,20-22], builded the LER assessment model and used the spatial autocorrelation analysis to analyse the spatiotemporal distribution characteristics of LER in the study area in the past 20 years. The ecological environment of the TGRR has been improved by the protection policies in recent years, but in general, the ecological environment is very fragile. Therefore, it is necessary to make the LER assessment for this area. Combined with the LER analysis in the TGRR, the following suggestions are put forward. Firstly, for medium and high-grade ecological risk areas. Attach importance to the impact of urban construction and the increase of industries along the river on the ecological risks on both sides of the Yangtze River. Reduce anthropogenic disturbance of high vulnerable landscape types such as waters. Strengthen wetland protection to reduce the risk of soil erosion in the TGRR. Secondly, for low-grade ecological risk areas. Environmental governance should be strengthened, Establish an ecological buffer zone. Reduce the possibility of forest land and grassland degradation and prevent land desertification. In the future protection, the TGRR should respect the integrity and heterogeneity of the landscape, and respect the self-restoration of nature. The calculation methods and ecological significance of the parameters in the LER model were further elucidated in this paper by analysing a large number of researches. But the LER assessment is a complex process that requires considering multiple uncertainties. These factors determine the comprehensive evaluation results. In the LER assessment of the TGRR, the method and process need to be further improved.
Changes in the PLE-space influence changes in the landscape pattern of the TGRR, which in turn affects the ecological risk of the region. In this paper, we tried to use the ecological contribution rate of land-use transformation[14] and made a preliminary exploration of the strength of the PLE-space land-use types on the improvement and deterioration of the ecological environment. But it remains to be further analyzed in how to make the ecological environment index of different PLE-space land use types more in line with the objective reality. The results indicated that the changes in regional LER are associated with the transformation of the PLE land-use function type. Therefore, the control of regional land-use transformation, the rational planning of land use, and ecological environment protection should be strengthened. Implement the system of paid occupation of ecological land and the system of ecological space use control. Comprehensively improve the ecological environment governance and protection level in the TGRR. The paper provided a reference for land planning, sustainable development, and ecological civilization construction in ecologically fragile areas. Adhering to the principle of "ecology priority". Under the background of the integration of "dual carbon" goals and "multi-plan". The concept of "dual carbon" will be fully integrated into the territorial space planning, and play the overall leading role of planning in low-carbon space governance. Building a scientific and reasonable low-carbon territorial spatial pattern, limit territorial space development under the framework of "conditional planning". Comprehensively optimize human-land relations, and promote the low-carbon operation of the "economic-social-ecological" composite system[23]. ”
References
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Author Response File: Author Response.docx
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
