Lang Zhang

Urban microtopography plays an important role in regulating soil processes and vegetation performance in newly constructed green spaces, yet its effects on surface runoff, soil nutrients, and plant growth remain insufficiently quantified in urban relocation sites. This study investigated how slope gradient, slope position, and slope curvature influence surface runoff, soil nutrient distribution, and tree growth in Shanghai Expo Cultural Park. Field monitoring was conducted in 36 plots planted with Cinnamomum camphora and Ginkgo biloba in 2017, 2020, and 2024. Microtopographic characteristics were quantified using terrestrial and handheld three-dimensional laser scanning, point-cloud processing, and digital elevation models (DEMs), and plant growth, calculated runoff, and soil physiochemical properties were analyzed using analysis of variance (ANOVA) and regression analysis. Annual DBH increments were greatest on meso slopes (mean = 0.558 cm), followed by gentle slopes (0.513 cm) and abrupt slopes (0.511 cm). Growth was also greater at slope-tail positions than at slope-head positions and greater on concave slopes than on convex slopes. The mean calculated runoff increased from gentle to meso and abrupt slopes, and soil organic matter, total nitrogen, hydrolysable nitrogen, available phosphorus, available potassium, and cation exchange capacity were generally higher at slope-tail positions. These results indicate that micrographic design affects tree growth mainly through runoff-mediated redistribution of water and soil nutrients. These findings provide practical guidance for optimizing microtopographic design, tree species selection, and soil management in urban green spaces established on relocation sites.

The construction and maintenance of ecological corridors not only facilitate species migration and gene flow but also enhance ecosystem stability and resilience, providing critical support for achieving global carbon neutrality goals. Despite their importance, research on urban ecological corridors—specifically their role in carbon sequestration and emission reduction within urban environments—remains insufficiently explored. To address this gap, we employed bibliometric and network analysis methods, utilizing the CiteSpace6.3.1 visualization tool to systematically review existing literature from the Web of Science Core Collection database. This study examines the research progress and trends in urban ecological corridors from 2000 to 2023, focusing on their role and significance in the context of global carbon neutrality. The findings reveal the following: (1) Research attention has grown steadily from 2000 to 2023, with climate change, carbon emission dynamics, and biodiversity emerging as core themes, reflecting increasing global focus on the carbon neutrality functions of urban ecological corridors. (2) CiteSpace analysis identified key research hotspots through keywords including climate change, carbon cycle, ecosystem services, model simulation, and ecological network analysis, revealing the functional mechanisms and pathways of urban ecological corridors in carbon neutrality contexts. (3) Current scientific challenges focus on understanding three core aspects of urban ecological corridors, the compositional elements, spatial structural design, and functional capacity assessment, requiring systematic theoretical breakthroughs. (4) Future research should prioritize exploring mechanisms to enhance urban ecological corridor functions and constructing low-carbon urban ecological networks, providing theoretical guidance and practical pathways for achieving urban emission reduction and climate goals. This study contributes to integrating research on the effectiveness of urban ecological corridors and carbon sinks, offering theoretical insights and practical guidance for reducing urban emissions and achieving climate goals.

Rapid urban development has exacerbated heat events. Vulnerable groups, due to deficiencies in physical functions and social support, often face higher health risks and survival pressures during heat events. Effectively identifying and assessing the heat risks they face and developing effective management strategies still pose many challenges. This study develops a heat risk assessment model based on the “hazard–accessibility–vulnerability” framework, incorporating circuit theory modeling to assess the health benefits of ventilation corridors for vulnerable populations and identifying high-temperature risk areas to better support science-based planning. The results show the following: (1) The urban heat island levels in the study area were classified based on the mean-standard deviation method, identifying that high-level heat islands account for 14.2% of the total area, with surface temperatures in urban built-up areas being significantly higher than in rural areas. (2) Based on the circuit theory model, 54 ventilation corridors were identified and 12 major corridors and 42 minor corridors were determined. (3) Based on the thermal risk assessment model, five residential areas covering 1.45 km² were identified as having the highest thermal risk, and 5.68 km² of residential areas had an imbalance between the ventilation demand and ventilation supply for vulnerable populations. This study innovatively assesses the health benefits of urban ventilation corridors from a social equity perspective and proposes urban renewal strategies such as introducing ventilation corridors, adjusting building layouts, enhancing green infrastructure, and promoting cooling technologies, offering new insights for future research.

In recent years, rapid urbanization in China has driven cities to expand uncontrollably into surrounding rural areas. Within the global context of ecological restoration, protecting and rehabilitating natural spaces have become key issues in landscape design. The concept of rewilding, rooted in wilderness philosophy, has gained significant attention. This article explores the background, significance, and theoretical foundations of rewilding urban ecological spaces using the woodland area of Heqing Country Park in Shanghai as a case study. It examines the feasibility, methods, and strategies for implementing rewilding in urban settings, considering both natural and human-influenced activities, with a focus on minimizing human intervention. This approach enhances biodiversity, promotes the sustainable development of ecosystems, and helps the park maintain its rural character despite its tourist appeal. Four years after the project’s implementation, research data show that the richness of native plant species, the diversity of bird species, and insect populations have exceeded those of the previously maintained forest. Moreover, the rewilding landscapes have supported the natural succession of habitat communities, leading to a stable and revitalized ecosystem. The landscape improvements and visitor experiences have been highly positive. The reconstruction strategy developed in this project is expected to inform future ecological initiatives, such as country parks, promoting the harmonious development of human and natural environments and serving as a model for creating urban ecosystems where both can coexist sustainably.

Objective With urban development and land use expansion, the structure and layout of various land use types are in dynamic change, and the fragmentation of ecological space becomes an important problem faced in the process of urbanization. The development of complex urban systems is highly influenced by social factors and human interference, and simple extrapolation and prediction of empirical knowledge can hardly predict future changes in urban land use. In view of this, it is recommended to use future land use simulation technology to simulate the changes of urban green space ecological network driven by multiple factors, so as to produce more reliable simulation results, thus improving the foresight and scientificity of urban planning work. Taking the central urban area of Shanghai as an example, this research conducts multi-scenario simulations of future land use, and measures the connectivity of green space ecological network under different scenarios, so as to provide a basis for optimizing urban ecological space in the future. Methods The current land use data spanning the period from 2000 to 2020 are used as the base data, and raster data obtained are derived from 30 m×30 m rasters. Driving factors are screened, including population density, GDP distribution, distance to railroads, highways, and main roads, average annual climate/precipitation, etc., and the suitability probability of each type of land use is calculated. Taking 2000 as the base year, the land use scenario for the target year 2020 is simulated based on the PLUS model, and the spatial consistency between this simulation scenario and the actual status of land use in 2020 is compared in combination with the kappa coefficient and the overall accuracy. On the basis of satisfying the simulation accuracy, the land use changes in 2040 under different constraints are simulated, and the urban green space ecological network under multiple scenarios of future urban development is extracted. In addition, morphological spatial pattern analysis (MSPA) and functional connectivity measurement index analysis are implemented to explore the differences in structural connectivity and functional connectivity of urban green space ecological network under different scenarios in the future. Results 1) During the period from 2000 to 2020, within the central urban area of Shanghai, the area of green space decreases most significantly, indicating that the rapid urbanization process has disturbed the city’s green ecological network to a great extent. In 2040, the area of green space will decrease to different extents under the three land use simulation scenarios, with the decay rate of green space under the ecological conservation and development scenario being effectively controlled. 2) The ecological conservation and development scenario provides good protection for the ecological sources of green space, and the overall patch fragmentation is mitigated, with the area of its bridging and traffic circle categories being significantly higher than that of the natural development scenario and the economic priority development scenario, which indicates that under the ecological conservation and development scenario, the ecological network of the green space has a stronger corridor connectivity, and is able to effectively improve the diffusion of species and the flow of energy between the ecological sources. 3) Under the multiple simulation scenarios targeting 2040, the spatial distribution and importance of key patches under different development scenarios of green space ecological network are basically the same, and such patches typically have a better ecological substrate, so they should be especially protected in future urban development; the patches with higher delta probability of connectivity (dPC) indicate that they are more important for future connectivity of green space ecological network, but they may have poor connectivity at present, so they can be used as potential source patches of green space ecological network for integrated planning. Conclusion Compared to other scenarios, the decay rate of green space under the ecological conservation and development scenario targeting 2040 has been effectively controlled. In terms of structural connectivity (physical linkage), the green space ecological network has great corridor connectivity and stable network structure under the ecological conservation and development scenario. In terms of functional connectivity, important patches are crucial to the structural stability and socio-ecological functioning of the ecological network. Considering that the coordinated development of the economy and ecology is a long-term process, there is a long way to go to maintain the long-term ecological health of urban centers through policy regulation and planning guidance. In future urban construction, policy regulation and planning can guide the optimization of urban ecological space and maintain the healthy development of urban green space ecological network.

Wetlands, as vital components of urban ecological infrastructure, provide essential ecosystem services. However, they face increasing risks of degradation and loss due to their vulnerability, environmental changes, and human activities. Therefore, effective restoration efforts are urgently needed. This study adopts a novel approach by considering the urban–rural gradient and integrates land use data, ecological parameters, and anthropogenic factors in Hefei City. Through morphological spatial pattern analysis, principal component analysis, and affinity propagation, this study identifies and analyzes urban–rural gradients. Using the optimal parameter geographic detector, the drivers of wetland changes from 1990 to 2020 are quantitatively assessed across different urban–rural gradients in Hefei. The findings indicate the following. (1) A persistent reduction in wetland expanse throughout the study duration, diminishing from 1274.56 km² in 1990 to 1119.37 km² in 2020, constituting a decrement of 12.17%. (2) Based on geographic detector outcomes, disparate driving forces underpin wetland dynamics across urban–rural gradients, with urban locales predominantly influenced by organic carbon and the proportion of impervious surface factors. Meanwhile, in agricultural and semi-ecological villages, silt is the primary factor, while ecological villages are primarily modulated by both silt and gross domestic product factors. Additionally, synergistic interactions manifest heightened explanatory power. This study elucidates the mechanistic underpinnings of wetland dynamics along urban–rural gradients, providing pivotal insights for developing targeted wetland restoration and conservation policies pertinent to the urban–rural developmental trajectory in Hefei City. Concurrently, it offers relevant recommendations for the multifaceted stewardship and sustainable development of wetlands in Hefei City in the foreseeable future.

Urban green spaces (UGSs) are considered an important natural approach for improving urban climatic conditions, promoting sustainable urban development, and advancing the global “Carbon Peak and Carbon Neutrality” targets. Previous studies have found that different vegetation spatial morphologies significantly impact the capacity to obstruct and absorb CO₂, but it is not yet well understood which morphology can retain and absorb more CO₂. This study takes Nantong Central Park as an example and conducts a CFD (Computational Fluid Dynamics) carbon flow simulation for CO₂ under different vegetation spatial morphologies to identify their CO₂ retention and absorption effects. First, the carbon sink benefits of elements such as “vegetation, soil, and wetlands” within the park were calculated, and the elements with the highest carbon sink benefits were identified. Then, the park was divided into carbon welcoming zones, carbon flow zones, and carbon shadow zones for carbon flow simulation with the highest carbon sink benefits. The results show that in the carbon welcome area, the one-block long fan-shaped plant community with a spatial density of 40 m thickness can best meet the requirements of absorption and induction of a small amount of carbon dioxide, with the smallest air vortex and uniform distribution of carbon dioxide in the surrounding area. In the carbon flow area, combined with the visual effect, the planting pattern of 6 m spacing herringbone combined with natural structure was adopted, which has a good carbon dioxide blocking and absorption capacity. In the carbon-shaded area, a herringbone planting pattern with a total width of 40 m and a base angle of 60° was chosen, which had the strongest hindrance and absorption capacity. Urban park environment optimization can use Fluent simulation to analyze the flow of carbon dioxide between different elements affected by wind dynamics at the same time. Based on the results, the form, layout, and spatial distance are adjusted and optimized. This study can better guide the spatial layout of vegetation and contribute to the realization of the goal of “carbon peak and carbon neutrality”.

Urban ecological corridors play an important role in facilitating bird migration and maintaining biodiversity in urban landscapes as key connections between habitat patches. However, the effects of built environment characteristics of urban ecological corridors on bird diversity have not been well understood. In this study, we used Minhang District, Shanghai, as an example to describe the built environment of urban ecological corridors through three dimensions (habitat characteristics, degree of surrounding urbanization, and degree of slow-traffic connectivity). We calculated species richness, abundance, Shannon–Wiener index, and Simpson Index to assess bird diversity based on the bird observation dataset from the Citizen Science Data Sharing Platform. The effects of built environment characteristics of urban ecological corridors on bird diversity were quantified by the Generalized Linear Model. The results showed that: (1) There were significant differences in the built environment characteristics of urban ecological corridors, which formed the spatial differentiation pattern of bird diversity. (2) Different built environment features of urban ecological corridors have different impacts on bird diversity. Habitat suitability of urban ecological corridors was positively correlated with bird diversity, with birds preferring to inhabit waters with an area of more than 1 ha. The degree of urbanization was negatively correlated with bird diversity, with distance to the center of the area proving to have the strongest positive effect. The degree of slow-traffic connectivity proved that low-intensity human activities in urban ecological corridors had a lower impact on bird diversity. The above findings can provide scientific reference for the construction of urban and regional ecological networks in the future.

Context Wetlands persistently diminish due to their own vulnerability, along with the combined impact of changes in the ecological surroundings and interference from anthropogenic interventions. Comprehending the driving mechanisms of wetland changes is crucial for wetland conservation. Objectives This research seeks to analyze the dynamic change characteristics of wetlands in Hefei. The objective is to establish a framework for urban-rural gradient analysis, exploring the impact of ecological surroundings and anthropogenic interventions factors, as well as their interactions, on wetland dynamics across different urban-rural gradient regions. Methods In this research, an urban-rural gradient was defined utilizing a clustering indicator derived from the composition and configuration of land use. The optimal parameters-based geographical detector (OPGD) performed a quantitative statistical analysis of the driving forces behind wetland changes under different urban–rural gradients. Results The results indicate that: (1) From 1990 to 2020, wetland area exhibited an ongoing diminishing tendency. (2) The urban–rural gradient can be classified into four categories: urban, agricultural village, semi-ecological village, and ecological village. (3) The driving factors of wetland changes vary across different types of urban–rural gradient regions. The most significant factors influencing wetland changes in each type of gradient region during different periods are the cropland proportion, impervious surface, OC, silt, and GDP. (4) Interactions among driving factors generally exhibit stronger explanatory power. Conclusions The research results reveal the driving mechanisms that underlie wetland dynamics in different urban–rural gradient regions. This information supports the development of more targeted wetland restoration and protection plans, contributing to improved synergy between urban and rural development and ecological conservation efforts.