Nanjing City Research Articles

Research on the site selection of emergency medical facilities from the perspective of country parks

Post-epidemic era, human society entered the stage of epidemic prevention and control normalized, emergency medical facilities are an important means of epidemic prevention and control, attention-needed can provide construction sites for emergency medical facilities. Disaster prevention and green space can provide construction sites for emergency medical facilities. In comparison, it was found that the site selection conditions of country parks and emergency medical facilities were more compatible. Based on the requirement of the latter's location, using the Delphi method and analytic hierarchy process, through to the country park type, effective safety area, space fragmentation, distance away from the water, in the wind, away from the city center distance, hydrogeology, eight factors such as traffic is quantitative, construct the evaluation system of emergency medical facility location. Taking Nanjing as an example, the Nanjing city region within the scope of the 43 country parks comprehensive comparison. Results show that green hill forest park, the highest scores in addition to the traffic time factor, the remaining seven factor score the highest, the most balanced distribution, security, scalability, rehabilitation, convenience, pollution prevention, and evacuation. It can be preferred as the site selection and construction target of emergency medical facilities. Besides, the Youzishan Forest Park and Dongkeng Country Park comprehensive scores and each factor score is higher, can be used as emergency preplan alternative goals. The score results indicate that the evaluation method for severity exhibits higher levels of differentiation, significant validity, and highly consistent assignment of impact factor weights. In view of the different regional land, impact factor weights assignment can be adjusted adjust measures to local conditions, to effectively make use of the existing conditions, avoid adverse factors.

Spatial accessibility dynamics of urban parks in Nanjing, China: implications for spatial equity

PurposeThis study aimed to explore the spatial accessibility dynamics of urban parks and their driving forces from 1901 to 2010 in terms of the dynamic relationships between spatial morphology and road networks, taking Nanjing City as an example.Design/methodology/approachThis study mapped and examined the spatiotemporal distribution of urban parks and road networks in four time points at Nanjing: the 1910s, 1930s, 1960s and 2010s, using the analysis methodology of spatial design network analysis, kernel density estimation and buffer analysis. Two approaches of spatial overlaying and data analysis were adopted to investigate the accessibility dynamics. The spatial overlaying compared the parks' layout and the road networks' core, subcore and noncore accessible areas; the data analysis clarified the average data on the city-wide and local scales of the road networks within the park buffer zone.FindingsThe analysis of the changing relationships between urban parks and the spatial morphology of road networks showed that the accessibility of urban parks has generally improved. This was influenced by six main factors: planning implementation, political policies, natural resources, historical heritage and cultural and economic levels.Social implicationsThe results provide a reference for achieving spatial equity, improving urban park accessibility and supporting sustainable urban park planning.Originality/valueAn increasing number of studies have explored the spatial accessibility of urban parks through the relationships between their spatial distribution and road networks. However, few studies have investigated the dynamic changes in accessibility over time. Discussing parks' accessibility over relatively long-time scales has practical, innovative and theoretical values; because it can reveal correlational laws and internal influences not apparent in short term and provide reference and implications for parks' spatial equity.

Collaborative agglomeration level and spatial correlation of intercity manufacturing industry: An empirical study based on the cities of the Yangtze River Delta.

Taking 27 cities in the Yangtze River Delta as an example, the time section data from 2009 to 2019 are selected, and the location entropy index and the modified E-G index are introduced to measure the collaborative agglomeration level of intercity manufacturing industry in the Yangtze River Delta. The spatial weight matrix is constructed based on the highway mileage between cities. Using Moran's index and Local Moran's index, this article analyzes the spatial correlation of the collaborative agglomeration level of intercity manufacturing industry in the Yangtze River Delta. The results show that: Firstly, the overall agglomeration degree of manufacturing industry of cities in the Yangtze River Delta shows a fluctuating downward trend. The agglomeration degree of manufacturing industry in Jiangsu and Zhejiang Provinces has decreased, that of most cities in Anhui Province has increased steadily. Secondly, the collaborative agglomeration level of manufacturing industry between Shanghai, Nanjing, Hangzhou and other cities in Jiangsu and Zhejiang Provinces showed a downward trend, while the collaborative agglomeration level with Anhui cities increased steadily. The collaborative agglomeration level of manufacturing industry between Wuxi, Suzhou, Nanjing and cities with obvious advantages in manufacturing industry agglomeration degree shows an upward trend, while the collaborative agglomeration level with other cities has declined. The collaborative agglomeration level of intercity manufacturing industry in Hefei has generally improved, especially the collaborative agglomeration quality and depth of manufacturing industry between Hefei and other cities in Anhui Province have significantly improved. Thirdly, the regions with high collaborative agglomeration level of intercity manufacturing industry in the Yangtze River Delta are still mainly concentrated in Jiangsu and Zhejiang Provinces. Although there has been a trend of westward transfer in the past decade, the overall change range is small, and the spatial correlation of the collaborative agglomeration level of intercity manufacturing industry shows a weakening trend as a whole.

Quantification and characterization of microplastics in farmland soils of Jiangsu Province, East China.

The soil ecosystem plays a significant role in the dynamics of microplastics. Qualitative and quantitative analyses of microplastics in six farmland plots from the cities of Nanjing, Suzhou, and Xuzhou were conducted by using laser infrared imaging system (LDIR). The results showed that the abundance of microplastics in farmland soils in Jiangsu Province ranged from 667-9333 items/kg, and the difference between the abundance of microplastics in soils from open-field cultivation and greenhouse farming was not significant. The vertical distribution characteristics showed that the abundance of microplastic decreased significantly with the increase of soil depth. However, there was no significant difference in particle size between top soil (0-5cm) and deep soil (10-20cm). Fragments were the most common microplastic form in soil samples (94.6%), with polyvinyl chloride (PVC) being the main polymer type, followed by polyethylene terephthalate (PET). Compared with previous studies conducted in China, the abundance of microplastics in farmland soils in Jiangsu Province was at moderate level but was notably higher than other places within the Yangtze River Delta region. The conclusions drawn from this paper provided important reference data for future assessment of microplastic pollution in agricultural fields. Furthermore, they establish a fundamental groundwork for understanding the migration patterns of MPs in soil environments.

Investigating the dynamicity of sentiment predictors in urban green spaces: A machine learning-based approach

Urban green spaces (UGSs) are known to promote psychological restoration. However, most traditional studies measure this effect statically using preset assumptions or scenarios, and tend to neglect factors’ varied effect under different conditions. In this study, we investigated the dynamicity of UGS-related factors on human sentiment under different UGS sizes and seasons by analysing social media reviews using machine learning. To this end, first, self-reported online reviews of UGSs in Nanjing City were collected. Next, machine learning-based text mining and natural language processing were performed to extract the latent topics and sentiment level of each review document, respectively. A logistic regression model series was established to analyse the influential valence of the review topics on the sentiment of the reviews. The results revealed that people’s sentiments and corresponding predictor performances are more sensitive to variations in UGS sizes compared with the seasons. Within UGSs, natural and activity features play more important roles in promoting positive sentiments compared with cultural and facility features. Moreover, larger UGSs include more tools that promote positive sentiments, and waterside activities and daily exercise promote positive sentiments throughout the year. Compared with previous studies, this study adopted a dynamic perspective to examine the influence of UGSs on people’s sentiment and provides a new approach in environmental psychoanalysis by integrating different ML-based techniques. Our findings are expected to aid in future decision-making during UGS planning and design in Nanjing and similar cities worldwide.

Changes in paleo-groundwater levels revealed by water wells and their relationship with climate variations in imperial Southern China.

Based on records of the bottom elevations of 511 ancient water wells from published archaeological reports, we reconstructed the paleo-groundwater levels (PGWL) in urban areas of Chengdu, Changsha, Nanjing, Suzhou, Suqian, Yancheng, Fuzhou, and Guangzhou cities in southern China. Our PGWL reconstruction shows that PGWL varied in two patterns. In the inland monsoon region (Chengdu and Changsha), there was a low PGWL in Jin (AD 266-420) and South Song (AD 1127-1279), and a high PGWL in Tang (AD 618-907) and Ming (AD 1368-1644). In the coastal region (Yancheng, Fuzhou, and Guangzhou), there was a low PGWL in Jin (AD 266-420) and Ming (AD 1368-1644) but a high PGWL in Tang (AD 618-907) and Song (AD 960-1279). Via cross-wavelet transform and wavelet transform coherence analyses, we found that monsoon and temperature significantly drove the PGWL fluctuations at the inter-centennial scale. East Asian Summer Monsoon-induced precipitation has continuously affected cities in the inland monsoon area represented by Chengdu and Changsha over the past 2,500 years. It has also intermittently affected Nanjing and Suzhou when EASM intensified. In parallel, temperature influenced the PGWL in coastal cities such as Yancheng, Fuzhou, and Guangzhou via the changes in the sea level. Also, the temperature affected the PGWL in relatively inland cities during climatic anomalies such as the Medieval Warm Period and Little Ice Age. This study demonstrates the value of archaeological records in learning how climatic factors influence the PGWL variation and its mechanism.

Optimal parameters of random forest for land cover classification with suitable data type and dataset on Google Earth Engine

Exact land cover (LC) map is essential information for understanding the development of human societies and studying the impacts of climate and environmental change. To fulfill this requirement, an optimal parameter of Random Forest (RF) for LC classification with suitable data type and dataset on Google Earth Engine (GEE) was investigated. The research objectives were 1) to examine optimum parameters of RF for LC classification at local scale 2) to classify LC data and assess accuracy in model area (Hefei City), 3) to identify a suitable data type and dataset for LC classification and 4) to validate optimum parameters of RF for LC classification with a suitable data type and dataset in test area (Nanjing City). This study suggests that the suitable data types for LC classification were Sentinel-2 data with auxiliary data. Meanwhile, the suitable dataset for LC classification was monthly and seasonal medians of Sentinel-2, elevation, and nighttime light data. The appropriate values of the number of trees, the variable per split, and the bag fraction for RF were 800, 22, and 0.9, respectively. The overall accuracy (OA) and Kappa index of LC in model area (Hefei City) with suitable dataset was 93.17% and 0.9102. In the meantime, the OA and Kappa index of LC in test area (Nanjing City) was 92.38% and 0.8914. Thus, the developed research methodology can be applied to update LC map where LC changes quickly occur.

Using Dual Spatial Clustering Models for Urban Fringe Areas Extraction Based on Night-time Light Data: Comparison of NPP/VIIRS, Luojia 1-01, and NASA’s Black Marble

Night-time light data (NTL) have been extensively utilized to map urban fringe areas, but to date, there has not been a comprehensive evaluation of the existing spatial clustering methods for delineating the urban fringe using different types of night-time light data. Therefore, we first selected three popular sources of night-time light data (i.e., NPP/VIIRS, Luojia 1-01, and NASA’s Black Marble) to identify the urban fringe. The recognition of spatial mutations across the urban–rural gradient was conducted based on changes in night light intensity using a spatial continuous wavelet transform model. Then, we employed three representative dual spatial clustering approaches (i.e., MK-Means, DBSC, and DSC) for extracting urban fringe areas using different NTL. By using dual spatial clustering, the spatial patterns of the mutation points were effectively transformed into homogeneous spatially adjacent clusters, enabling the measurement of similarity between mutation points. Taking Nanjing city, one of China’s megacities, as the study area, we found that (1) Compared with the fragmented and concentrated results obtained from the Luojia 1-01, NASA’s Black Marble and NPP/VIIRS data can effectively capture the abrupt change of urban fringes with NTL variations; (2) DSC provided a reliable approach for accurately extracting urban fringe areas using NASA’s Black Marble data.

Influence of Urban-Road Green Space Plant Configurations on NO2 Concentrations in Nanjing City during Winter

The rapid urbanization and growing number of motor vehicles in China have led to a significant increase in NO2 emissions, posing a severe threat to the air quality in cities. Road traffic pollution has emerged as a significant environmental issue in China. Exploring the utilization of landscape plants for air pollutant mitigation and assessing the influence of various plant concentrations on reducing air pollution holds great significance in urban ecological environment protection and urban development. Through field surveys and data collection in January 2022, the objectives of this study are to explore the relationship between road meteorological factors and the reduction in air pollutant concentrations in Nanjing city’s road green spaces and to investigate the influence of plant configuration in road green spaces on pollutant concentration. The findings demonstrate a distinct positive correlation between road traffic volume during winter peak hours and the concentration of NO2 pollution gas. Furthermore, meteorological factors, including temperature and light intensity, strongly correlate with air pollutant concentrations. Open green spaces with ventilated structures and high tree planting density (deciduous trees are preferred) exhibit optimal purification effects. Excessive or insufficient planting density hinders the purifying function of green belts. In conclusion, our research on plant configurations and air pollutant concentrations in Nanjing City during the winter suggests that the recommended road green space plant configuration in Nanjing is a combination of arbor (deciduous tree), shrub, and grass.

Entering Anthologies with Names: The First Generation of Courtesan Poets in Ming Dynasty Nanjing

Abstract This article traces the first generation of Ming courtesan poets and the earliest extant anthology recording both their poems and full names. These pioneering courtesan poets emerged from anonymity in the city of Nanjing during the late fifteenth and early sixteenth centuries. They represented a new mode of literary production and circulation in the context of social, economic, and cultural transformation which began in the mid-Ming. To better situate courtesan poets within the Ming world of letters, we examine the various sources recording their biographical information and literary/artistic creations.

Measurement and Spatial Correlation Analysis of the Development Level of the Digital Economy in the Yangtze River Delta Urban Agglomeration

The Yangtze River Delta Urban Agglomeration (YRDUA) is the core area for the development of China’s digital economy. This paper constructed a five-dimensional evaluation index system and measured the digital economy development level of the YRDUA. A modified gravity model social network analysis was applied to analyze the structure of the digital economy network. The results show that (1) the level of digital economy in the YRDUA has increased during 2011–2021, with Hangzhou having the highest digital economy development level of 0.513 in 2021. (2) The digital economy network density of the YRDUA increased from 0.155 in 2011 to 0.158 in 2016, and then decreased to 0.151 in 2021, showing an “inverted U-shaped” trend of first increasing and then decreasing. (3) Shanghai, Suzhou, Nanjing, Hangzhou, and Wuxi play the role of “bridge” in the digital economy network, and the pattern of linkage development of neighboring cities driven by the central cities of Shanghai, Nanjing, Suzhou, Hangzhou, Ningbo, and Hefei has basically formed. These findings of the study provide data support and reference for the coordinated development of the digital economy in the YRDUA and are of theoretical and practical significance for the synergistic development of cities.

BIPV Generation Efficiency Optimal Scheme—— Take Jiangning District of Nanjing City for Example

Building Integrated photovoltaic (BIPV) is more and more applied to the construction field with its advantages of being close to the load center, saving urban land and building materials. Especially under the current goal of 'carbon peak' and 'carbon neutrality', the integration of photovoltaic buildings is one of the important ways to achieve the effective application of renewable energy in buildings. But at present, the lack of relevant application cases of the technology, many owners interested in BIPV have remained on the sidelines. This paper mainly focuses on the economic and environmental benefit evaluation of the roof and curtain wall system of BIPV. By comparing the economic benefits and investment payback period, the owners provide the optimal investment plan, and analyzes the significance of 'two-carbon policy' by calculating the environmental benefits of BIPV. In this paper, Jiangning District of Nanjing city is taken as the pilot object to analyze the benefit of BIPV, and proposed the optimal design strategy of building photovoltaic integration suitable for this area through the benefit comparison of different schemes. In the roof and curtain wall benefit evaluation when we use the photovoltaic garden analysis site for solar radiation estimates, and then get the whole life cycle of photovoltaic system capacity, as the basis of economic benefit evaluation, then through the query related data to save the total coal as the basis of environmental benefit evaluation, combined with the project investment payback period, economic benefits and environmental benefits of comprehensive evaluation of the final plan. Through the above economic benefits and environmental benefits data comparison, photovoltaic roof has more investment value than photovoltaic curtain wall in both economic and environmental aspects. Taking Jiangning District of Nanjing city as an example, this paper illustrates the broad prospect of BIPV, and also provides a relatively clear data support and case reference for the promotion of BIPV nationwide in the future.

Study on Settlement of Self-Compacting Solidified Soil in Foundation Pit Backfilling Based on GA-BP Neural Network Model

In order to predict the settlement of self-compacting solidified soil in foundation pit backfilling, finite element software is used to study the influence of soil properties and the surrounding structural properties of the foundation pit on the settlement of backfilled self-compacting solidified soil based on a foundation pit project in the city of Nanjing. The degree of influence of various factors influencing settlement is considered, a grey relational grade analysis is conducted, and input layer parameters of the neural network are determined based on the results of the grey relational grade analysis. Based on the GA-BP neural network model, the settlement of soil is predicted using numerical simulation results. The results reveal that the settlement and structural disturbance of self-compacting solidified soil after backfilling are smaller than those of fine silty sand; self-compacting solidified soil significantly improves the engineering performance of excavated soil. In the grey relational grade analysis, the six influencing factors that have high correlation with soil settlement can be used as input layer parameters for the neural network model. Among them, the correlation degree between elastic modulus and soil settlement is the highest, reaching 0.8402. The correlation degrees of the remaining five influencing factors are above 0.5, and the values are close. The GA-BP neural network can improve the overfitting situation of a BP neural network trapped in local optima, with R2 reaching 0.9999 and RMSE only 0.0018 mm, achieving high-precision prediction of settlement of self-compacting solidified soil.

Dynamic change and evolutionary mechanism of city land leasing network—Taking the Yangtze River Delta region in China as an example

Mapping city networks has attracted scholarly attention in urban studies, while the relevant studies focusing on land elements are lacking. This study aims to address and fill this research gap by analyzing across-city land leasing relationships. Using Yangtze River Delta region (YRDR) in China as a case, we explore the dynamic change and evolutionary mechanism of city land leasing network based on urban land leasing data and temporal exponential random graph model (TERGM). The findings reveal that: 1) At the macro level, as the interconnections between cities in the YRDR grow stronger, the inter-city flow of land elements has become growingly convenient and accessible, there is a corresponding increase in the frequency of land use rights transfer between cities. This has led to the emergence of a more intricate and interconnected city land leasing network in the YRDR. 2) At the medium level, city land leasing network in the YRDR fosters land leasing communities within province boundary. Shanghai community is identified as the strongest community, which establish a compact relationship with a large number of cities in Zhejiang, Jiangsu, and Anhui provinces. The province of Zhejiang, Jiangsu, and Anhui have also foster communities with provincial capitals as the core, respectively. 3) At the individual level, Shanghai is the primary recipient city in terms of cross-city land leasing relationships, followed by provincial capital cities of Hangzhou, Nanjing, and Hefei. 4) Significant effects, including endogenous structural effects, actor-relation effects, exogenous network effects, and time effects, could be found in the city land leasing network of the YRDR. The city land leasing network in the YRDR is influenced by endogenous structural factors such as popularity, transitivity, and connectivity. Cities with low economic development levels, strong land leasing intervention, high real estate development investment levels, and high land leasing prices are more likely to lease land to other cities. Cities with higher levels of economic development, higher levels of industrial structure upgrading, higher levels of real estate development investment, and higher land prices are more likely to lease land from other cities. Furthermore, cities within the same province or within Yangtze River Delta Urban Agglomerations (YRDUR) are more likely to foster inter-city land leasing relationships, while the distance between cities negatively affects the establishment of inter-city land leasing relationships.

Integrating landscape ecological risk into ecosystem service value assessment: A case study of Nanjing City, China

The scientific assessment of ecosystem service value (ESV) and landscape ecological risk (LER) is important for ecological security and sustainable development. However, existing studies often separate ESV and LER for a single evaluation, and the single evaluation is limited in guiding ecological conservation. Therefore, proposing an evaluation framework that integrates ESV and LER is urgent. Taking Nanjing City as an example, this study evaluated LER based on the risk evaluation cell and introduced it into ESV evaluation. Then, the influence of land use/land cover change on LER and ESV from 2000 to 2020 was analyzed. The results showed that built-up land and water body/wetland increased by 881.96 km2 and 41.41 km2, and farmland and forest land decreased by 875.46 km2 and 55.83 km2 from 2000 to 2020. The LER was low in the middle and high in the north and south. From 2000 to 2010, the LER increased from 0.67 to 0.68, and it then decreased to 0.61 in 2020. Medium-low risk regions decreased during 2000–2010, and low-risk regions increased and medium-high risk regions decreased during 2010–2020. The ESV increased by 0.77 billion United States dollars (USD) during 2000–2010 but decreased by 0.40 billion USD during 2010–2020. Under the impact of LER, the ESV per unit area of the farmland, forest land, and water body decreased during 2000–2020. The ESV of the water body dominated the total ESV and had an important influence on the change in total ESV. The ESV in Nanjing City during 2000–2020 mainly showed High-High autocorrelation and a few Low-High autocorrelations. Ecological restoration programs increased ESV during 2000–2010, but rapid urbanization reduced ESV during 2010–2020. Integrating social, economic, and ecological resources is necessary to realize the coordinated development of the economy and ecology. The results can provide an important reference for landscape planning and ecosystem management.

Assessment of Ecological Benefits of Urban Green Spaces in Nanjing City, China, Based on the Entropy Method and the Coupling Harmonious Degree Model

Urban green spaces (UGSs) are an important spatial carrier for carbon sequestration in the national land space. The urban ecosystem is a highly harmonious composite ecosystem of nature, society, and the economy. Therefore, this study constructed an evaluation system of the UGS ecological benefit based on two subsystems–the natural environment and the social economy–in order to quantitatively evaluate the construction level of the UGS ecological benefit in Nanjing City and to reveal its temporal evolution characteristics. The entropy method was applied to assess the ecological benefits of UGSs in Nanjing City, China, from 2011 to 2020. The coupling harmonious degree model was utilized to analyze the dynamic coordination relations among subsystems. The Robust regression analysis was used to verify the evaluation results. The results showed that: (i) Between 2011 and 2020, UGS ecological benefits in Nanjing City exhibited a substantial and consistent upward trend. (ii) Between 2011 and 2020, the coupling harmonious degree among the subsystems of UGS ecological benefits in Nanjing City showed an overall rising trend of fluctuation. With the enhancing of the coupling harmonious degree among the subsystems of UGSs, the ecological benefit of UGSs will be significantly improved. (iii) The comprehensive evaluation score of the social and economic subsystem of UGS in Nanjing City was higher than that of the natural environment subsystem; this highlights the significant constraints posed by the natural environment on the construction of UGSs in Nanjing City. The research conclusion provides a decision basis for realizing the collaborative optimization of the natural environment and the social economy in Nanjing City and further promotes the sustainable development of the UGS ecological environment.

Sleep and subjective well-being among chinese adolescents

Introduction: The relationships among sleep, resilience, and subjective well-being (SWB) are less studied in adolescents. This study aimed to examine the associations between multiple sleep domains (sleep duration and quality, and chronotype) and SWB in Chinese adolescents, and whether resilience mediated these relationships. Methods: We enrolled 455 adolescents in Jintan and Nanjing cities (Jiangsu Province, China) in 2017–2018. Sleep variables included sleep duration (time in bed [TIB], interval between bedtime and waketime), sleep quality (global score of the Pittsburgh Sleep Quality Index [PSQI]), and chronotype (mid-sleep time on weekends corrected for sleep debt). We used the Chinese version of the Connor–Davidson Resilience Scale to measure resilience, and the satisfaction with Life Scale and Subjective Happiness Scale to measure SWB. Mediation analyses were performed using structural equation modeling with a bootstrap approach. Results: The associations between sleep duration/sleep quality and SWB were fully mediated by resilience. Specifically, longer TIB (B = 2.04, P = 0.03) and lower PSQI scores (B = −1.60, P < 0.001) were associated with greater resilience, which in turn, was associated with greater latent SWB constructed from happiness and life satisfaction (BTIB = 0.12, BPSQI = 0.11, P < 0.05). Later chronotype was associated with lower happiness (B = −0.52, P = 0.01) and life satisfaction (B = −0.76, P = 0.02) but not resilience and latent SWB. Conclusion: Sleep duration and sleep quality were positively associated with latent SWB, and resilience is a mediator. Later, chronotype was independently associated with lower levels of SWB indicators, including happiness and life satisfaction. The study findings highlight the importance of optimal sleep in promoting resilience and SWB during adolescence.

Investigating the impacts of urban built environments on users of multiple services in elderly care facilities

This paper aims to characterize the varied urban settings community-based elderly care facilities are located, and examine whether characteristics of urban built environments influence the number of older people attending care facilities for multiple services. The dataset incorporates 108 cases of community-based elderly care facilities and usage records from over 17000 users collected in the Chinese city of Nanjing. A network-based approach was employed to comprehensively describe urban built environments surrounding care facilities with a series of metrics on street morphology and land-uses. It was found that urban built environments significantly influenced the number of users attending care facilities. Facilities having more users tended to locate in places with more shops and stores, on major arterial streets of the city, or inside large housing estates in the outer city. Moreover, urban factors performed differently in affecting users of different services as services accepting spontaneous users were more likely to be influenced by street morphology. This study revealed specific urban factors facilitating older people's usage of care resources. It also generated practical implications regarding the strategies for the planning of spatial locations and service provision to improve the utilization of community-based elderly care.

Spatial Changes of Suburban Forest Ecological Functions and Their Impact on Ecological Equity in the Process of Urbanization—A Case Study of Jiangning District, Nanjing, China

After the transformation of counties in urban suburbs into districts, the rapid urbanization and industrialization process in China’s developed regions had a huge impact on the spatial distribution and equity of the suburban forest ecological functions. Accurately describing this impact could provide an important reference for the construction of suburban forest engineering and for ecological environmental planning. Jiangning District of Nanjing City, China, was selected as the research area, while the forest resource planning and design survey data in 2007 and 2017, together with the demographic data of the study area, were collected as the main information sources. Following the establishment of the forest ecological function evaluation indicators and the analysis of the spatial change of the forest ecological functions, the Gini coefficient was calculated to analyze the changes of the regional ecological function equality. The results showed that: (1) Compared with 2007, the proportion of areas with low forest ecological functions (abbreviated as FEF) in the study area in 2017 showed a downward trend, and the proportion of areas with medium and high FEF showed an increasing trend; (2) Compared with 2007, the forest landscape in the study area in 2017 was severely fragmented, the spatial aggregation of the FEF showed a significant decline, and the FEF developed towards a direction of spatially balanced distribution; (3) During 2007–2017, the sub-compartments with high-value FEF in the study area (hot spots) shifted to the northwest, where the economy was developed and the population density was higher, and the sub-compartments with low-value (cold spots) shifted to the south, where the economy is underdeveloped and with lower population density; (4) From 2007 to 2017, the Gini coefficient of the FEF in the study area decreased, indicating that the regional ecological equity had initially improved. The urbanization and industrialization process of the urban suburbs is a double-edged sword. On the one hand, the process has caused the fragmentation of forest landscape, the decline of the forest area, and the unbalanced spatial distribution of the population. On the other hand, the huge material wealth and human capital accumulated through industrialization have promoted regional ecological equity and improved the living environment of the local residents.

Quantifying the relationship between urban blue-green landscape spatial pattern and carbon sequestration: A case study of Nanjing’s central city

Against the background of global warming, urban blue–green spaces (UBGS) are important carbon sequestration (CS) carriers that can reduce carbon emissions. However, previous studies on urban CS were mostly limited to urban green or blue spaces separately and lack a comprehensive consideration of the synergistic impact of UBGS on CS. In addition, research on the driving mechanism between urban blue–green spatial patterns (UBGSP) and CS has so far been insufficient. Therefore, in this study, we explored the correlation between UBGSP and CS, identified the affecting UBGSP factors, and proposed suggestions for planning design. We identified the UBGS of the central city of Nanjing based on Landsat-8, calculated the CS using the Carnegie-Ames-Stanford approach (CASA), and analyzed the relationship between the UBGSP and CS at both class and landscape levels by establishing sets of UBGSP indicators. At the class level, the percentage of landscape and aggregation index have positive effects on CS, whereas the landscape division and shape indexes have negative effects. Moreover, edge density and area-weighted patch fractal dimension do not correlate with CS. At the landscape level, connectance can promote the CS of UBGS. Finally, we found that the largest patch index, edge density, Shannon’s evenness index, patch cohesion index, and contagion have no significant effects. The results of this study contribute to the systematic optimization of UBGSPs, promote the integrated development of UBGSs, and provide references for urban planning practices and resource management.