Urban Ecological System Research Articles

Research on Urban Resilience from the Perspective of Land Intensive Use: Indicator Measurement, Impact and Policy Implications

Land intensive use reflects the spatial structure, agglomeration characteristics, and internal mechanisms of urban economic, social, and ecological system development, significantly impacting urban resilience. Based on panel data from 287 cities in China from 2010 to 2020, this paper measures the levels of land intensive use and urban resilience, and empirically examines the impact mechanism of land intensive use on urban resilience through baseline regression and panel quantile regression. The results reveal that: (1) During the study period, China’s urban land intensive use level has significantly improved. The land intensive use level shows a trend of “the strong become stronger, and the weak are always weak” and “high in the east and low in the west” spatial differentiation, while the urban resilience level showed a trend of accelerated “catching up” of low-resilience cities towards high-resilience cities and “high in the east and low in the west” spatial differentiation as well. (2) Land intensive use significantly promotes effect on urban resilience, and the effect depends on different conditions. (3) Among all dimensions of land intensive use, both land input intensity and land use benefits significantly promote urban resilience, while land use intensity shows an insignificant effect. (4) The impact of land intensive use on urban resilience demonstrates significant scale heterogeneity and geographic regional heterogeneity. Based on these findings, the paper proposes relevant policy suggestions for land intensive use aimed at improving urban resilience, offering guidance for promoting high-quality land use and sustainable urban resilience development.

Thinking and Analyzing the Construction of Urban Ecological Network System of Territorial Spatial Planning

Thinking and Analyzing the Construction of Urban Ecological Network System of Territorial Spatial Planning

Spatial–temporal distribution and key factors of urban land use ecological efficiency in the Loess Plateau of China

Urban land use ecological efficiency is crucial to the urbanization process and urban ecosystem sustainability. Cities in ecologically sensitive zones with frequent natural disasters need more complex land use patterns and plans. Achieving the goal of harmonizing economy and ecosystem is key for sustainable development policy makers in these cities. Aiming to explore the urban land use ecological efficiency (LUEE) of ecologically sensitive areas, urban land use ecological efficiency index system of the Loess Plateau was constructed, the SBM-Tobit model was adopted to measure the LUEE and influencing factors from 2009 to 2018, and the characteristics of spatial–temporal evolution was discussed. The results indicated that there were significant spatial differences of LUEE in ecologically sensitive zone. The high-level cities of LUEE were located in the southwest areas, while low-level cities of LUEE were mostly situated in the northeast zones, and the temporal variation trend showed the characteristic of “W” curve. Additionally, the results of key factors identification demonstrated that science and technology expenditure and public transport development had positive effects on urban LUEE, while the land expansion, GDP growth, the second industry and real estate development will limit the improvement of urban LUEE. This study used the scientific evaluation index system and key factors identification method to explore the land use ecological efficiency in ecologically sensitive zones, aiming to provide a case study reference for urban land management and optimization in ecologically fragile areas.

Coordination Analysis of Urban Forest and Urban Development Level: A Case Study of the Yangtze River Delta Urban Agglomeration, China

With the rapid development of the Yangtze River Delta urban agglomeration, sustainability and high-quality development have become the key paths to regional development. The urban forest, referring to the sum of trees, forests, and green space in an urban area, provides a series of ecological benefits and economic values and is essential to the urban ecological system. In the post-urbanization period, the integrated development of urban forests and the city is attached with great importance to long-term development. From the perspective of regional and coordinated development, this research constructed an evaluation index system of urban development and urban forest development. Then, a comprehensive evaluation model and coordination degree model were adopted to systematically study the temporal and spatial characteristics and policy influencing factors on the coordination degree between urban development and urban forest development in the Yangtze River Delta urban agglomeration from 2005 to 2021. The results showed that from 2005 to 2021, urban development displayed continuous growth, while urban forest development exhibited a fluctuating increase and the level of urban forest generally lagged behind that of urban development. From 2005 to 2021, the coordination degree of the Yangtze River Delta urban agglomeration showed a fluctuating trend, of which the maximum value was 0.999 in 2012, the minimum value was 0.730 in 2021, and the coordination degrees were all at the level of good coordination or high-quality coordination except for 2021. In terms of spatial distribution, three provinces and one city all showed a fluctuating increase at first, followed by a downward trend, while Shanghai showed the highest coordination level. From the perspective of policy on urban forests, the Shanghai government showed the best effort, while the Jiangsu government still needs improvement. This research provides a scientific basis for coordinating the relationship between urban development and the environment and for realizing regional sustainable and high-quality development.

Exploring the coupling coordination of urban ecological resilience and new-type urbanization: The case of China’s Chengdu–Chongqing Economic Circle

Reviewing the coupling coordination between urban ecological resilience (UER) and new-type urbanization (NU) has gradually become a necessary condition for understanding the structure and service patterns of urban ecological systems. Discussion on the temporal and spatial coordination evolution in UER and NU in urban agglomerations with different characteristics is beneficial for understanding the operational mechanisms of urban ecosystems. This work constructs a novel evaluation framework for the coupling coordination process between UER and NU, and scientifically measures the performance of each indicator using the entropy method and CRITIC method. By using the coupling coordination degree (CCD) model, this paper explores the spatio-temporal effects of the relationship between UER and NU, which has narrowed the cognitive gap. Using the Chengdu–Chongqing Economic Circle in China as an example, the validity and practicality of the framework are verified. The results show that the CCD between UER and NU generally shows a rapid growth trend with time and tends to be balanced; and the development patterns of CCD in urban agglomerations show significant spatial differences influenced by factors such as location advantage, natural resources, and human social activities. These results and findings can provide decision-making information reference for urban ecological system services, urban livability, and government planning.

Urban Vegetation Extraction from High-Resolution Remote Sensing Imagery on SD-UNet and Vegetation Spectral Features

Urban vegetation plays a crucial role in the urban ecological system. Efficient and accurate extraction of urban vegetation information has been a pressing task. Although the development of deep learning brings great advantages for vegetation extraction, there are still problems, such as ultra-fine vegetation omissions, heavy computational burden, and unstable model performance. Therefore, a Separable Dense U-Net (SD-UNet) was proposed by introducing dense connections, separable convolutions, batch normalization layers, and Tanh activation function into U-Net. Furthermore, the Fake sample set (NIR-RG), NDVI sample set (NDVI-RG), and True sample set (RGB) were established to train SD-UNet. The obtained models were validated and applied to four scenes (high-density buildings area, cloud and misty conditions area, park, and suburb) and two administrative divisions. The experimental results show that the Fake sample set can effectively improve the model’s vegetation extraction accuracy. The SD-UNet achieves the highest accuracy compared to other methods (U-Net, SegNet, NDVI, RF) on the Fake sample set, whose ACC, IOU, and Recall reached 0.9581, 0.8977, and 0.9577, respectively. It can be concluded that the SD-UNet trained on the Fake sample set not only is beneficial for vegetation extraction but also has better generalization ability and transferability.

Mapping of Ecological Environment Based on Google Earth Engine Cloud Computing Platform and Landsat Long-Term Data: A Case Study of the Zhoushan Archipelago

In recent years, with the rapid advancement of China’s urbanization, the contradiction between urban development and the ecological environment has become increasingly prominent, and the urban ecological system now faces severe challenges. In this study, we proposed an ecological index-based approach to monitor and evaluate the ecological environment using a Google Earth Engine cloud-based platform and Landsat time series. Firstly, a long-term series of Landsat images was obtained to construct and calculate the remote sensing-based ecological index (RSEI). Then, the Theil–Sen median estimation and the Mann–Kendall test were used to evaluate the trend and significance of the RSEI time series and combined with the Hurst index to predict the future development trend of the ecological environment in the study area. Finally, the coefficient of variation method was used to determine the temporal stability of the ecological environment. Taking Zhoushan Archipelago, China, as the study area, we mapped the distribution of the ecological environment using a spatial resolution of 30 m and evaluated the ecological environment from 1985 to 2020. The results show that (1) from 1985 to 2020, the average RSEI in the Zhoushan Archipelago decreased from 0.7719 to 0.5817, increasing at a rate of −24.64%. (2) The changes in the areas of each level of ecological environmental quality show that the ecological environment in the Zhoushan Archipelago generally exhibited a decreasing trend. During the study period, the proportion of the areas with excellent ecological environmental quality decreased by 38.83%, while the proportion of areas with poor and relatively poor ecological environmental quality increased by 20.03%. (3) Based on the overall change trend, the degradation in the ecological environment in the Zhoushan Archipelago was greater than the improvement, with the degradation area accounting for 84.35% of the total area, the improvement area accounting for 12.61% of the total area, and the stable area accounting for 3.05% of the total area. (4) From the perspective of the sustainability of the changes, in 86.61% of the study area, the RSEI exhibited positive sustainability, indicating that the sustainability of the RSEI was relatively strong. (5) The coefficient of variation in the RSEI was concentrated in the range of 0–0.40, having an average value of 0.1627 and a standard deviation of 0.1467, indicating that the RSEI values in the Zhoushan Archipelago during the study period were concentrated, the interannual fluctuations of the data were small, and the time series was relatively stable. The results of this study provide theoretical methods and a decision-making basis for the dynamic monitoring and regional governance of the ecological environment in island areas.

Design of urban ecological landscape visualization system by using visual 3D model

Design of urban ecological landscape visualization system by using visual 3D model

Spatial Network of Urban Heat Environment in Beijing-Tianjin-Hebei Urban Agglomeration Based on MSPA and Circuit Theory

Rapid urbanization has increased the complexity of the urban heat environment system, which has negative impacts on the health of the urban ecological system and the human habitat. By combining theories and technologies such as geographic information systems, remote sensing, morphological spatial pattern analysis, and circuit theory with data from MODIS land surface temperature production, urban heat island patches in the Beijing-Tianjin-Hebei urban agglomeration were quantitatively identified in terms of their spatial and temporal distribution characteristics and their spatial and temporal transfer paths. This foundation revealed the geographical network structure of the urban heat environment as well as the spatial and temporal evolution process of critical corridors. According to the findings, urban heat island patches covered 16610 km2 in 2020, accounting for 7.68% of the study area. In the Beijing-Tianjin-Hebei urban agglomeration, both the area and the number of urban heat island patches considerably increased between 2005 and 2020, going from being dominated by isolated island types of urban heat island patches in 2005 to being dominated by core types in 2020. In particular, the non-urban heat island patches, core type, and edge type of urban heat island patches in 2005 were the major ancestors of the core type and edge type urban heat island patches in 2020. In the Beijing-Tianjin-Hebei urban agglomeration, there were more urban heat environment source sites, corridor length, densities, and present densities in 2020 than there were in 2005. The sensitive corridor was found to be the predominant type of urban heat island corridor in the Beijing-Tianjin-Hebei urban agglomeration in 2020. The number of sensitive corridors increased the highest in the period from 2005-2020. As the coefficient of urban heat environment corridors increased concurrently, it was apparent that the urban heat environment corridor had a propensity to grow continuously in the Beijing-Tianjin-Hebei urban agglomeration. The active adaptation and mitigation measures of the urban heat environment were proposed, and a spatial network model of the urban heat environment was finally provided. To adapt to, mitigate, and promote urban sustainable development risks, these research findings will serve as a paradigm for the identification of the urban heat environment spatial network actively and methodically.

Connotation of urban ecological quality and the construction of its core index system.

Urban ecological quality is a necessary attribute for a healthy urban ecological state. In the period of urban development from large-scale incremental construction to stock improvement and quality transformation and incremental structural adjustment, there are many gaps between urban ecological quality construction and the requirements of the new stage. There is an urgent need to understand and integrate multiple needs, and construct an indicator system to promote the balance between supply and demand of ecological resources and efficient use to enhance urban ecological quality. We used the analysis methods of CiteSpace literature analysis, relevant policy collation and questionnaire survey to systematically sort out the key points of concern and differences in understanding among the three perspectives of science, government, and the public. The results showed that all the three perspectives, i.e., science, government, and public, were more concerned with indicators related to urban green space, gray infrastructure, and policy control. The concerns of science and public addressed indicators related to urban green space the most, while government being most concerned with indicators related to gray infrastructure. Based on those findings, we developed a core urban ecological quality index system with a total of 25 indicators, covering 10 major types of urban green space, environmental quality, gray infrastructure, and so on.

Urban ecological network construction in Loess Plateau regions in China-case study of Huanxian city

Cities in ecologically vulnerable areas have high ecological sensitivity, and the balance between urban expansion and the ecological environment is easily broken, leading to various environmental problems. These problems seriously interrupt the sustainable health development of urban ecosystems. Studying urban ecological network construction from the perspective of multifactor ecological processes is of important significance to the ecological safety and resource management of cities. In this study, an analysis of ecological elements was conducted separately to account for the “vertical” and “horizontal” ecological processes present in the ecological network. By using the superposition mode of vertical ecological processes, the composition of vital ecological patches was analyzed, and important ecological patches within the ecosystem were identified through ecological sensitivity evaluation index system. On the other hand, the composition of ecological corridors was analyzed through the use of horizontal ecological processes. The biological corridor was determined by source identification of biological processes and resistance surface analysis while the catchment corridor was determined through runoff simulation. Based on these findings, it was possible to propose an urban ecological network construction system specifically designed for Loess Plateau regions using a superposition of ecological sensitivity, biological processes, and catchment processes. Finally, a case study of the urban ecological network system of Loess Plateau regions was conducted in Huanxian City. Comparing the proposed urban ecological network of the Loess Plateau regions and the generated scheme with the overall planning scheme of 2016, the patch density and the largest patch index decreased by 1.522 and 13.794, respectively, while the fractal dimension, interspersion and juxtaposition index, the contagion index, and the connectivity index increased by 0.003, 2.188, 14.076, and 1.366, respectively. This trend proves that the research scheme improved in terms of ecological performance. Research conclusions can provide useful references for the construction of urban ecological networks in underdeveloped and ecologically vulnerable areas in China while offering guidelines for making decisions on the green development and management of urban spaces.

The Construction of Ecological Security Pattern under Rapid Urbanization in the Loess Plateau: A Case Study of Taiyuan City

Taiyuan City in the eastern Loess Plateau has experienced severe ecological problems caused by urban expansion. For cities undergoing rapid urbanization, building an ecological security pattern (ESP) is an effective means to improve urban resilience. Here, geographic information systems (GIS) were used to analyze, manipulate, and visualize urban ecological multi-source information and remote sensing (RS) for the history of land use/land-cover (LULC) changes and the structure of the urban ecological system. Four important ecosystem service functions were estimated: soil conservation, habitat quality, water yield, and carbon storage. The minimum cumulative resistance (MCR) model was combined with the circuit theory method to determine the ecological corridors, pinch points, and barrier points. Our results showed that: (1) from 1980 to 2020, Taiyuan’s built-up area showed increased construction land and enhanced landscape fragmentation. The decline in cultivated land was mainly attributed to construction land. During the period from 2000 to 2010, a greater amount of land was changed in Taiyuan than in other periods; (2) The ecosystem service evaluation based on the LULC in 2020 revealed that the central urban area was lower than the other areas; (3) 38 ecological source sites were identified, accounting for 16% of the total study area. An area of 106 km2 was allocated to construct 79 ecological corridors. We identified 31 ecological pinch points and 6 ecological barrier points; (4) an ESP optimization governance model of “two rings, four zones, and nine corridors” was proposed. Our study provides theoretical guidance for sustainable development and ecological design in Taiyuan City and other regions.

Evaluation of Sustainable Development of the Urban Ecological Environment and Its Coupling Relationship with Human Activities Based on Multi-Source Data

Combining the travel modes of human activities, fully mining multi-source data, and analyzing the relationship between the urban ecological environment and human activities are important topics in urban ecological environment planning. Human activity indicators were constructed based on the data of POI points, OSM road network, and residential areas. Machine learning models such as support vector regression machine, extreme gradient boosting regression, polynomial regression, and random forest regression were combined with remote sensing images to construct an urban ecological environment indicator system. These models were used to conduct regression analysis of urban ecological environment indicators and human activity indicators in Chengdu, China. The research shows that the three indicators of human activities all show a trend of increasing in the center and gradually decreasing in the surrounding areas, while the sustainable urban ecological environment indicators show the opposite trend. On the relationship between urban ecological environment and human activities, XGB has the best effect; the correlation between the street vitality index and the urban function mixing index and the sustainable urban ecological environment is stronger, and the correlation between the walkability measure index of the residential area and the sustainable urban ecological environment is even worse.

An ecological environment impact assessment of municipal solid waste based on grey prediction model

Aiming at the problem of low accuracy in the impact assessment of urban waste on ecological environment, a method of urban waste ecological environment impact assessment based on grey prediction model is proposed. First, the pollution type of urban waste is determined, and the important pollution data of urban waste is extracted with the help of the calculation of comprehensive water quality identification index. Then, the total ranking of pollution data is determined by the square root method, the judgement matrix is set to calculate the weight of pollution data, and the urban waste ecological environment pollution index system is constructed. Lastly, with the help of grey prediction model, the positive correlation between urban waste and ecological environment is determined, and the urban waste ecological environment impact assessment algorithm is designed to complete the impact assessment. The results show that the evaluation accuracy can be effectively improved by using the evaluation method in this paper.

Study on evaluation and construction of ecological livable cities in western underdeveloped areas—Take Guiyang as an example

<p>Building a sustainable, ecological, and livable city is the inevitable choice of current urban development. The evaluation of ecologically livable cities plays an important role in guiding the construction direction and development trend of ecologically livable cities. From the aspects of economic development, infrastructure, ecological environment, and social people’s livelihood, build an urban ecological livable evaluation index system, use the entropy weight method to determine the index weight, and use the matter-element analysis method to build an evaluation model to evaluate the construction of ecological livable cities in Guiyang City, Guizhou Province, from 2005 to 2015. Research shows: that from 2005 to 2015, the level of ecological livability in Guiyang increased significantly, realizing the development transformation from “not livable” to “ideal livable”, but the level of “ideal livable” was unstable in 2015. The key factors restricting the construction of an ecologically livable city in Guiyang are the insufficient area of urban roads, the low comprehensive utilization rate of industrial solid waste, and the insufficient investment in the transformation and protection of the ecological environment. The matter-element model can not only obtain the comprehensive quality information of the research object but also reveal the differentiation information of individual indicators, which is suitable for the evaluation of ecologically livable cities.</p>

Ecological Smart City Construction Based on Ecological Economy and Network Governance.

China has paid huge resources and environmental costs in the rapid economic development, which severely restricts China's sustainable development. As a mesolevel between macro(state) and micro(enterprise), urban management has many features that are different from traditional management. This research mainly discusses the construction of ecological smart city based on ecological economy and network governance. This research analyzes the current situation and problems of urban construction from three aspects: urban ecological economy, urban ecological environment, and urban ecological society. The ecological indicators of smart cities are used to reflect the true situation of the target. In order to facilitate quantitative analysis with the greatest possibility and accuracy, a batch of representative, comprehensive, and quantifiable indicator data is the key. By drawing on the existing literature and implementing it under the circumstances, the selected methods are frequency analysis and theoretical analysis, which are divided into three parts: economy, environment, and society to construct an urban ecological evaluation index system. Under the new network governance environment, the openness of government affairs has become more transparent and time-effective. Moving the government's work to the network not only enhances the construction of a clean government, but also increases the level of public participation. The main ways of citizen participation created by network governance are carrying out online voting, making anonymous online speeches, and online inquiries about politics, etc. These ways have expanded the traditional government governance methods. Not only that, network governance can make the government's management process more transparent. In this situation, government activities are carried out under the supervision of citizens, which can alleviate the phenomenon of corruption. After the implementation of the ecological smart city plan, the green coverage rate of the built-up area of City A will increase by 1.8% compared with 2017, showing an upward trend. This research will provide effective guidance for the development of ecological smart cities.

Sustaining Human Nutrition in an Increasingly Urban World

The complex interaction between social, economic, and environmental processes coupled with transformations of the landscape primarily driven by urbanization have impacts on the access, availability, and distribution, of food. This has resulted in a global micronutrient deficiency and hunger. Given rapid urbanization and population growth, a more sustainable food system is necessary to feed more urban populations and provide adequate nutrition, especially in developing countries. Existing frameworks for modelling urban-environment interactions contain components related to food security, however, lack the specificity needed to evaluate the effects of land use decisions and agricultural production strategies on the health of local populations measured through metrics such as nutritional output. The research presented here proposes an urban nutrition (UN) extension to the previously published urban ecological economic system by developing a focused component that simulates scenarios of different degrees of urbanization and agricultural production techniques to improve the nutritional output of agricultural land, while considering the conservation of soil. This simulation approach was subsequently applied to the Toluca Metropolitan Zone, Mexico. Results showed that nutritional output would greatly increase when adding a variety of crops, even in scenarios where agricultural land is limited. The proposed extension can be used by decision makers worldwide to evaluate how landscape configurations and agricultural production systems affect the nutritional needs of the local population while fostering sustainable practices.

Exploring the Interactive Coercing Relationship between Urban Rail Transit and the Ecological Environment

The Chinese environment is experiencing the “U-Type” course from sharp deterioration to significant improvement. In order to achieve the fundamental improvement of the ecological environment, China has implemented several relevant policies and strategies. Among them, the development of urban rail transit, as an essential measure to improve the ecological environment in China, has attracted more and more attention, but the research on the interactive coercion relationship between rail transit and the ecological environment is minimal. Therefore, this study selected ten cities opening urban rail transit before 2005 in mainland China as research objects and established an urban rail transit and ecological environment comprehensive evaluation index system. Then, the interactive coercing model and coupling coordination model were used, and the dynamic relationship between urban rail transit and the ecological environment was explored. The research results in this study showed that (1) there is an apparent interactive coercion relationship between urban rail transit and the ecological environment, and the evolution trajectory conforms to a double exponential curve. (2) From 2006 to 2019, Wuhan’s ecological environment pressure index showed a continuous downward trend. The ecological environment improved the fastest. The rest of the cities showed a trend of first rising and then falling. (3) The type of coupling coordination degree of urban rail transit and ecological environment showed a changing coordination trend from severe incoordination—slight to incoordination—basic to coordination—good. Beijing has the highest degree of overall coordinated development in urban rail transit and the ecological environment. The results of this study can provide a theoretical reference for the realisation of the virtuous circle development of rail transit and the ecological environment.

基于空间演变多元分析的市域生态空间优化研究——以宁波市为例

市域生态空间是城乡发展的绿色基底和生态基础，其协同联系"山水林田湖草"各生态系统，是动植物和自然生态多种过程的空间载体，同时也是人类进行社会经济活动的场所，与城乡经济社会发展息息相关，良好的市域生态空间体系，是实现市域层面生态系统稳定，协调城市发展和自然保护的重要载体，同时也是实现城市健康良性发展的重要保障。现有的市域生态空间规划重视不够，其静态的、定性为主的规划方法严重滞后，存在一系列不足与缺陷：1）重城区，轻市域；2）重主观定性，轻客观定量；3）重被动落实，轻主动响应；4）重静态蓝图，轻动态模拟。其空间规划成果远不能达到预期，无法应对城市化对市域生态环境和资源所带来的影响和威胁。以宁波市域空间为对象，以市域生态空间演变为出发点，从生态空间的安全格局、结构特征和用地类型转移3个方面，通过对2000年、2010年和2018年3个时期的市域空间演变的定量化分析，揭示市域生态空间演变的特征与规律。并以此为基础探索新型市域生态空间重构的方法和内容，提出空间优化的策略：针对安全格局层面生态适宜性衰退、结构层面连通度下降、地类层面绿色空间减少的问题等，通过确定生态核心，构建绿色空间廊道，筛选关键节点，对其分别进行分级、保护，最终重新构建起良性的宁波市域生态空间体系，并针对优化结果进行评价与修正。从市域生态空间3种类型演变分析入手，以"演变-响应-重构"为逻辑指导市域生态空间规划，积极探索了应对城市化影响下市域生态空间优化的新方法，为市域山水林田湖草生命综合体的资源保护和科学利用提供了一定的理论。;Urban ecological space is the green base and ecological foundation of urban and rural development, which is synergistically linked to the ecosystems of landscape, water, forest, field, lake and grass, and is the spatial carrier of various processes of flora and fauna and natural ecology, as well as the place for human socio-economic activities, and is closely related to urban and rural economic and social development. A good urban ecological space system is an important carrier to realize the stability of the ecosystem at the municipal level, to coordinate urban development and nature protection, and also an important guarantee to realize the healthy and benign development of the city. The existing municipal ecological spatial planning does not pay enough attention to its static, qualitative-oriented planning methods, which are seriously lagging behind, with a series of deficiencies and defects:1) emphasis on urban areas rather than municipalities; 2) emphasis on subjective qualitative rather than objective quantitative; 3) emphasis on passive implementation rather than active response; 4) emphasis on static blueprints rather than dynamic simulations. Its spatial planning results are far from meeting expectations and cannot cope with the impacts and threats brought by urbanization on the ecological environment and resources of the urban area. This paper selects Ningbo urban space as the object, takes the evolution of urban ecological space as the starting point, and reveals the characteristics and laws of the evolution of urban ecological space from three aspects:security pattern, structural characteristics and land use type transfer of ecological space, through the quantitative analysis of the evolution of urban space in 2000, 2010 and 2018. Based on this, we explore the methods and contents of the new municipal ecological space reconstruction and propose strategies for spatial optimization:to address the problems of declining ecological suitability at the security pattern level, declining connectivity at the structural level, and decreasing green space at the land type level, etc., by identifying ecological cores, organizing green space corridors, screening key nodes, grading and protecting them respectively, and finally reconstructing a benign Ningbo municipal ecological Spatial system of Ningbo city is reconstructed, and the optimization results are evaluated and revised. This study starts from the analysis of the evolution of three types of urban ecological space, and uses the logic of evolution-response-reconstruction to guide the urban ecological space planning, and actively explores a new method for optimizing the urban ecological space under the influence of urbanization, which provides a certain theory for the protection and scientific utilization of resources in the urban landscape, forest, field, lake and grass life complex.

Evaluation Indexes and Spatial-Temporal Features towards Urban Resilience of Sichuan Province in China from 2003 to 2013

New pattern urbanization, which is explored and developed in China for improving urban resilience and reducing urban vulnerability. Urban resilience is a comprehensive ability of a city for dealing with the uncertainty risk disasters through a combination of urban economy, urban engineering, urban society and urban ecology. When the city system and its subsystems have certain resilience in development, it will promote sustainable development. How to assess urban resilience? What is the spatial-temporal law on the development of urban resilience? These answers have an important practical significance for promoting the construction of the modern urbanization and sustainable development of cities and regions. Based on the above, this study constructed the measurement system on urban resilience, chose 21 cities of Sichuan province in China as a case, and analyzed the spatial-temporal law on the development of urban resilience empirically. The conclusions are as follows: The level of urban resilience was on the rise, and the characteristics of spatial heterogeneity on urban resilience were presented, and the spatial agglomeration degree increased gradually. The resilience of urban economic system, urban engineering system, and urban ecological system revealed a cluster characteristic in Sichuan province, but urban social system was not obvious.