Policy-Driven Scenarios for Sustainable Peri-Urban Land Use: Production–Living–Ecological Space in Yubei District, Chongqing

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Review of manuscript "Policy-Driven Scenarios for Sustainable Peri-Urban Land Use: Production-Living-Ecological Space in Yubei District, Chongqing" (land-3595434)

This manuscript tries to use the transformation of production-living-ecological (PLE) spaces in Yubei District, a peri-urban district in Chongqing between 2005 and 2020, as the baseline. The projections were simulated for 2035 under four scenarios, highlighting the impacts of varying land use policies. Although it fits the scope of this journal, its contribution to land use science needs to be enhanced. More detailed comments are shown in the following:

- . The introduction is too long and reviews the background and policies in too much detail, which leads to a deviation in the reader's understanding of the core issues.

- . The literature review section covers less of the latest land use simulation research in the past two years and needs to be significantly supplemented.

- . The Research Methods section is a mixture of data, preprocessing, and methodology, and thus lacks organization.

- . The manuscript does not explain in detail the data preprocessing steps, including outlier processing and data cleaning. For example, the acquisition and standardization methods of driving factor data (GDP, population) are not clear, which may affect the accuracy of model input.

- . In addition, the manuscript does not mention how to deal with the spatial consistency of data from different sources, especially the integration method of 30-meter resolution land use data and 1:1 million administrative boundary data.

- . In the scenario setting, only four scenarios are briefly introduced, but the specific assumptions, parameter settings or constraints of each scenario are not clarified, such as the adjustment of land conversion probability and specific measures for ecological red line protection.

- . The selection basis and weight allocation method of the driving factors of land use change simulation are not clear. Please refer to:

National-scale connectivity analysis and construction of forest networks based on graph theory: A case study of China

Spatial and Temporal Analysis of Habitat Quality in the Yellow River Basin Based on Land-Use Transition and Its Driving Forces

- . The economic development scenario assumes that the expansion of construction land does not exceed 1.3 times that of 2020, but does not explain how this threshold is compatible with the ecological protection red line of Chongqing's land and space planning, which may underestimate the complexity of policy implementation.

- . The verification of the land use model relies only on the Kappa coefficient and the overall accuracy, and detailed FoM results need to be provided.

- . Figure 3 shows the comparison between the simulation and the actual situation in 2020, but does not explain whether the error in the expansion from southwest to northeast is related to the model's failure to consider emergency policies.

- . The fundamental contradiction between scenario S1 and the ecological protection goal of ECCDA is not deeply analyzed, such as how "no reduction in ecological function" can coexist with the expansion of construction land.

- . The comparative analysis of different scenarios is not in-depth enough to highlight the advantages and disadvantages of each scenario. It is necessary to strengthen the comparative analysis of scenarios and evaluate the potential impact of each scenario from multiple dimensions, including ecology, economy and society.

- . The adaptability of the model to rapid urbanization is not discussed, such as whether the acceleration of urbanization after 2015 will lead to the failure of historical trend extrapolation.

- . The discussion section is not deep enough, and the discussion of policy conflicts and trade-offs is superficial, lacking multi-dimensional comparison and innovative insights.

- . The conclusion section believes that the green development and farmland protection scenarios can significantly improve ecological quality, but does not fully consider the complexity and uncertainty of policy implementation.

Comments on the Quality of English Language

The English could be improved to more clearly express the research.

Author Response

Please see attachement.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

Introduction

The introduction provides a solid contextualization of China’s regulatory framework, integrating the concept of “ecological civilization” and the unified territorial spatial planning system (TSP). However, the narrative is overly normative and optimistic regarding the impact of these policies, omitting concrete problems derived from the real implementation of such models. To address these issues, it is recommended to include a brief critical reference to the phenomenon of Chinese ghost cities (https://doi.org/10.1007/978-981-97-8776-0_6 / https://doi.org/10.1007/978-3-030-31776-8_4) and, in the case of Yubei, to question whether the district could be at risk of following similar patterns under certain scenarios (particularly RS and S1). It would also be advisable to introduce the concept of urban resilience as a central analytical axis, alongside sustainability. Cities must not only grow in an orderly fashion but also be able to absorb, adapt to, and recover from crises or unexpected transformations (https://doi.org/10.1016/j.futures.2024.103399).

 

Research Method

The methodology is solid in terms of quantitative tools (Markov-FLUS) and scenario-based design. The multi-scenario simulation approach is highly relevant. However, the evaluation of ecological impacts relies on a single aggregated index, which may limit the analysis of resilience or specific ecosystem services. To address this, it is suggested to include a discussion on specific ecosystem services such as water regulation, air quality, or recreation, which may be affected by the conversion of ecological space into urban land (https://doi.org/10.18172/cig.5638). Likewise, it would be appropriate to incorporate additional indicators of urban resilience, such as ecological connectivity, functional land-use diversity, or equitable access to green space. Consider integrating metrics into urban underutilization or mismatches between land use and population growth as a proxy for estimating risks of ghost urbanism.

 

Results

The results show clear differences between scenarios, especially the contrast between accelerated urban growth (RS, S1) and ecological or agricultural containment strategies (S2, S3). However, there is a lack of critical discussion regarding the long-term feasibility and risks associated with each scenario. In the RS scenario, where urban growth is deregulated, it is recommended to explicitly warn about the risk of generating urbanized areas without real demand, as seen in ghost cities such as Ordos or Tianjin Eco-City. In the case of S1, the analysis should go beyond economic efficiency to also examine its potential impact on ecological fragmentation and the loss of essential ecosystem services. Finally, although S2 shows an increase in the environmental quality index, it is important to assess which ecosystem services are being protected or restored (e.g., water infiltration, temperature regulation, biodiversity).

 

Discussion

The discussion would benefit from a more incisive examination of the negative implications of certain scenarios and the integration of more complex frameworks such as nature-based planning and resilience theory. The model of extensive urban development should be critically examined, showing how it may contradict the logic of ECCDA (Ecological Civilization Construction Demonstration Area), generating tensions between political goals and urban realities. A reflection should be included on how poorly planned Chinese cities have become "infrastructures without life" due to a failure to integrate services, densities, and real user needs. Additionally, the concept of socio-ecological resilience should be better developed, analyzing not only land use but also the interaction between human and natural systems under conditions of stress or crisis.

 

Conclusions

The conclusion rightly highlights the value of S2 and S3 as more sustainable scenarios. However, it could be further strengthened by making a more ambitious call to rethink the urban model, focusing not only on sustainable expansion but also on livability, adaptive capacity, and long-term functionality.

Comments on the Quality of English Language

The English language throughout the manuscript is generally understandable but would benefit from careful revision to improve clarity, readability, and flow. Several sections contain long and complex sentences that could be simplified, and there are occasional issues with word choice, grammar, and syntax that may hinder comprehension. Improving the structure and transitions between paragraphs—especially in the Introduction and Discussion—would help the narrative flow more smoothly.

Author Response

Please see attachement.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for your replies and comments. Congratulations for the work