Urban-rural Fringe Areas Research Articles

Characterising the urban–rural fringe area (URFA) in China: a review of global and local literature on urban–rural fringe areas

Urban-Rural Fringe Areas (URFAs) in China have experienced significant change since 1978 due to extensive urban growth and sprawl. This article explores the characteristics of URFAs in China through a scoping review approach. Analysis identifies that URFAs in China possess features that are located in and connected to urban and rural areas, mixed land use, occupied by both urban and rural populations, and driven by changes in social structure, economic development and policy implementation. These findings are consistent with URFAs in a global context, illustrating synergies in academic and practitioner approaches. However, China’s URFAs are unique due to the country’s social structure, topographical diversity, divergent urban diversity and the regional variations that exist within urban development policies and strategies. The article contributes to a better understanding of the characteristics of URFAs in China, providing guidance for future policy to support more effective and sustainable development. This article was published open access under a CC BY licence: https://creativecommons.org/licences/by/4.0/ .

Construction of a Predictive Model for Diabetes Mellitus Type 2 in Middle-Aged and Elderly Populations Based on the Medical Checkup Data of National Basic Public Health Service

To establish a universally applicable logistic risk prediction model for diabetes mellitus type 2 (T2DM) in the middle-aged and elderly populations based on the results of a Meta-analysis, and to validate and confirm the efficacy of the model using the follow-up data of medical check-ups of National Basic Public Health Service. Cohort studies evaluating T2DM risks were identified in Chinese and English databases. The logistic model utilized Meta-combined effect values such as the odds ratio (OR) to derive β, the partial regression coefficient, of the logistic model. The Meta-combined incidence rate of T2DM was used to obtain the parameter α of the logistic model. Validation of the predictive performance of the model was conducted with the follow-up data of medical checkups of National Basic Public Health Service. The follow-up data came from a community health center in Chengdu and were collected between 2017 and 2022 from 7602 individuals who did not have T2DM at their baseline medical checkups done at the community health center. This community health center was located in an urban-rural fringe area with a large population of middle-aged and elderly people. A total of 40 cohort studies were included and 10 items covered in the medical checkups of National Basic Public Health Service were identified in the Meta-analysis as statistically significant risk factors for T2DM, including age, central obesity, smoking, physical inactivity, impaired fasting glucose, a reduced level of high-density lipoprotein cholesterol (HDL-C), hypertension, body mass index (BMI), triglyceride glucose (TYG) index, and a family history of diabetes, with the OR values and 95% confidence interval (CI) being 1.04 (1.03, 1.05), 1.55 (1.29, 1.88), 1.36 (1.11, 1.66), 1.26 (1.07, 1.49), 3.93 (2.94, 5.24), 1.14 (1.06, 1.23), 1.47 (1.34, 1.61), 1.11 (1.05, 1.18), 2.15 (1.75, 2.62), and 1.66 (1.55, 1.78), respectively, and the combined β values being 0.039, 0.438, 0.307, 0.231, 1.369, 0.131, 0.385, 0.104, 0.765, and 0.507, respectively. A total of 37 studies reported the incidence rate, with the combined incidence being 0.08 (0.07, 0.09) and the parameter α being -2.442 for the logistic model. The logistic risk prediction model constructed based on Meta-analysis was externally validated with the data of 7602 individuals who had medical checkups and were followed up for at least once. External validation results showed that the predictive model had an area under curve (AUC) of 0.794 (0.771, 0.816), accuracy of 74.5%, sensitivity of 71.0%, and specificity of 74.7% in the 7602 individuals. The T2DM risk prediction model based on Meta-analysis has good predictive performance and can be used as a practical tool for T2DM risk prediction in middle-aged and elderly populations.

Frontier Revitalisation of Industrial Heritage with Urban–Rural Fringe in China

The urban–rural fringe is at the forefront of the confrontation between the agricultural and industrial civilisations. How to handle the relationship between the two civilisations in this region and ensure its sustainable development is an eternal topic in the science of the human-living environment. Thanks to the special historical background of the Third Line construction, China’s industrial heritage connects with the urban–rural fringe that surpasses other countries. For the first time, this study connects China’s Third Line construction, industrial heritage, and urban–rural integration within the same context, combining big data bibliometric methods to obtain the development characteristics and context of China’s industrial heritage research starting from 2004. It has strong policy characteristics, is influenced by administrative orders, and is aligned with urbanisation efforts. Theoretical exploration is the first step in research, followed by value connotations and cultural qualities. It addresses various topics, including industrial heritage conservation, regeneration approaches, and cultural heritage tourism. The research focuses primarily on the value appraisal of industrial heritage, exploring revitalisation tactics and routes, as well as regional development models in urban–rural periphery areas. This study also examines how scholars generally consider the impact of industrial heritage on the economic, social, and cultural development of urban–rural fringe areas in order to integrate and propose various protection and utilisation strategies, such as industrial heritage preservation, cultural and creative industry development, and tourism resource development.

Investigating the microclimate impacts of blue–green space development in the urban–rural fringe using the WRF-UCM model

Blue–green spaces in the urban–rural fringe (URF) can help restrain endless urban sprawl and urban warming; however, the climate impact of these spaces has not been examined. Based on spatial transformation characteristics within the identified URF areas in Wuhan from 2000 to 2020, this study used the WRF-UCM model to observe microclimate impacts of different development modes and lake reduction in URF blue–green spaces. 1) Urban sprawl increased the average air temperature at 2 m (T2) by 0.82 °C and increased the 10-m wind speed (WS10) by 0.16 m/s in the city centre area. 2) The non-built-up areas (GW_CT) development mode reduced T2, with a maximum hourly cooling effect of 0.13 °C, and the open high-rise (GW_HR) and large low-rise (GW_LL) development modes increased the average nighttime T2 (with maximum hourly warming of 0.22 °C and 0.12 °C, respectively) as well as the WS10. 3) When built-up land expanded outwards and encroached on more than 25.89% of the lake area, the T2 and WS10 at the city centre significantly changed (0.17 °C and 0.1 m/s increased). This paper demonstrates the importance of conducting climate impact assessments for peri-urban blue-green space development.

Spatial Optimization of Land Use Pattern toward Carbon Mitigation Targets—A Study in Guangzhou

Global climate change is one of the major challenges facing the world, and the spatial optimization of land use patterns has been regarded as critical in realizing carbon mitigation. In this study, the linear programming model and the Markov Chain model are integrated in different scenarios to optimize land use structure for low-carbon development. The land use pattern is then simulated through the adjusted convolutional neural network and cellular automata model, taking Guangzhou City as the case study area. The results reveal that construction land with high economic efficiency will increase its area, and the reaming types will experience slight changes, in 2035 in the natural development scenario and the economic priority scenario. Ecological land such as forest land, grassland, and water is partly occupied by construction land in the urban–rural fringe areas. The total carbon emissions decrease by 2.32% and 1.57% in these two scenarios. In the low-carbon-oriented scenario, the expansion of construction land is restricted, and the forest land and grassland undergo great expansion. The total carbon emission decreases by 18.95%—a figure much larger than that in the natural development scenario and the economic priority scenario. Our paper embeds the needs and constraints in land spatial planning into the spatial optimization of the land use pattern, which provides valuable references for low-carbon city development in the future.

Investigating injury severity interaction between urban and urban-rural fringe areas: a grouped random parameters seemingly unrelated bivariate probit approach

Urban-rural integration is the critical process of urbanization, while during this process there are various corresponding problems generated, safety is the most important one, especially at urban-rural fringe areas due to mixed traffic flow and complicated land use. This study intended to investigate the injury severity interaction between urban area and urban-rural fringe area, and explore the correlation within injury severity levels and heterogeneity attributed to unobserved factors. To address the correlation and heterogeneity issues, a grouped random parameters seemingly unrelated bivariate (SUB) probit model was proposed, in which the SUB probit model addressed the correlation of residuals, while the random parameters model accommodated the heterogeneity due to unobserved factors. By comparing the pooled with random parameters models, the results showed that random parameters SUB probit model performed better than the pooled one, and the dataset collected from 2013 to 2017 in Chengdu, China was adopted to illustrate the proposed model. It is found that crash location, speed limit and age of person injured are significant for injury severity in urban and urban-rural fringe areas, but crash form plays a significant role in urban area while number of persons involved should be paid more attention due to injury severity in urban-rural fringe area. Some empirical suggestions are presented to improve the safety in urban and urban-rural fringe areas.

A practice study of land and water comprehensive remediation in urban-rural fringe-with Sichuan River Shaanxi Province, Northwest China, as an example.

Urban-rural fringe area (URFa) is an active and expansive region, and its environment is complex and frangible. Previous studies have focused on the landscape spatial pattern changes, the spatial-temporal variability of soil pollutants and the land management and policy issues, etc., but it is lack of the practice study of land and water comprehensive remediation in URFa. This article is taking the Sichuan River, a typical URFa, as an example. Based on field investigation and lab tests, the main characteristic form of the URFa and land and water comprehensive remediation measures are summarized in this paper. The results show that it is feasible to turn wasteland, low-efficiency land, and old deserted beach into farm land, residential land, and ecological land by comprehensive land improvement. For the farm land reconstruction, the texture is an important indicator. The content of soil organic matter (SOM), carbon, nitrogen, and phosphorus has increased after remediation. For the SOM, 58.3% are more than 10.0g·kg-1, and 79.2% are more than 8.0g·kg-1. For the frequent dry-off and polluted low flow river channels in URFa, the river bottom consolidation and water purification is the important measures. The water quality meets IV standard of the "Environmental Quality Standards for Surface Water" (GB3838-2002) (State EPA of China, 2002) by pollution treatment after remediation, and water volume keeps balance. The findings of this study are expected to provide support for better construction practices in arid and semiarid area in China and for the improvement of the ecological environment in URFa.

Assessing Land-Use Conflict Potential and Its Correlation with LULC Based on the Perspective of Multi-Functionality and Landscape Complexity: The Case of Chengdu, China

The rapid development of megacities has greatly impacted land use in the urban–rural fringe area. The Western Protected Area defined by Chengdu’s Master Plan (2016–2035) to end the unrestrained urban sprawl, where locates the most superior agricultural and ecological resources, namely Mount Qingcheng and the Dujiangyan Essence Irrigation District, is facing great challenges when implementing protective strategies, related to huge land use competition caused by land multi-functionality. To better assess and understand land-use conflict and its influence, this paper constructs a comprehensive evaluation model with ‘multi-functionality and landscape complexity’ based on existing research, with a 1 km × 1 km spatial resolution, and analyzes its relationship with land-use and land-cover (LULC) change, based on 30 m land resolution data from 2000, 2010, and 2020, produced by the Institute of Resource and Environmental Science and the Data Center of the Chinese Academy of Sciences. Overall, two kinds of land-use conflict concerning function suitability and landscape pattern co-emerge spatially, but there also exist “high-low” combinations. The result shows that land consolidation or the adjustment of land use might take place more often when both the suitability conflict and the landscape conflict reach a certain threshold. The results provide enlightenment for further expanding the quantitative research on land-use conflict and confirm the potential of applying the land-use conflict index in delineating territorial spatial planning control areas.

Black carbon in contrasting environments in India: Temporal variability, source apportionment and radiative forcing

Analyses of black carbon (BC) data from three different environments in India - Delhi megacity, Srinagar metropolitan and Gulmarg hill station, showed that Delhi had the highest annual average BC concentration (12.3 ± 10.2 μg m−3), followed by Srinagar (4.3 ± 5 μg m−3) and Gulmarg (2.4 ± 2 μg m−3). The inflow of aerosols from the neighboring agricultural regions, notably during Winter, causes Delhi to have the highest seasonal average BC (16.8 μg m−3). Srinagar had the highest average seasonal BC during autumn (6.3 μg m−3) due to the burning of horticulture residue and hardwood for charcoal making and residential heating. At Gulmarg, on the other hand, the winter season's high BC (2.2 μg m−3) is due to the increased emissions from the tourist traffic, snowmobile/ATVs and wood burning for residential heating. BC concentrations in Delhi and Srinagar were roughly in line with their population size. However, compared to sites with the similar population, BC at Gulmarg was roughly twice higher than the other sites. There was a higher contribution to BC from fossil fuels than biomass burning at all three sites, which indicates that cars are the primary source of BC. Overall, values of BC aerosol optical properties in Delhi are much higher than those in Srinagar and Gulmarg. During the cold season, continental air masses transport BC from the neighboring areas to Delhi and westerlies enhance the local BC loading at Srinagar and Gulmarg. The predominant presence of absorbing aerosols, particularly BC, during late autumn and winter at all three sites leads to an increase in aerosol optical depth (AOD), a reduction in single scattering albedo (SSA) and an increase in asymmetry parameter (AP). As a result, there is a significant increase in the radiative forcing of the atmosphere (RFATM), with the highest values observed in January in Delhi (+71.5 W m−2) and Srinagar (+56.05 W m−2), and in November at Gulmarg (+18.5 W m−2). These findings suggest that small rural towns that are affected by seasonal emissions, low planetary boundary layers, and frequent temperature inversions, can contribute to a substantial amount of radiative forcing. This study provides a larger perspective on increasing BC in Delhi, and urban-rural fringe areas in the Indian Himalayas, which is crucial for identifying what actions must be taken to control BC emissions to reduce impacts on cryosphere, human health and other sectors.

Research on Spatial Delineation Method of Urban-Rural Fringe Combining POI and Nighttime Light Data—Taking Wuhan City as an Example

The boundary delineation of the urban-rural fringe (URF) is the basic work of fine planning and governance of cities, which plays a positive role in promoting the process of global sustainable development and urban and rural integration. In the past, the delineation of URF had shortcomings such as a single selected data source, difficulty in obtaining data, and low spatial and temporal resolution. This study combines Point of Interest (POI) and Nighttime Light (NTL) data, proposes a new spatial recognition method of URF according to the characteristics of urban and rural spatial structure, and conducts empirical analysis with Wuhan as the research object, combining the information entropy of land use structure, NDVI, and population density data to verify and compare the delineation results and field verification was conducted for typical areas. The results show that (1) the fusion of POI and NTL can maximize the use of the characteristics of the differences in facility types, light intensity, and resolution between POI and NTL, compared with the urban-rural fringe boundary identified by POI, NTL or population density data alone, and it is more accurate and time-sensitive; (2) NPP and POI (fusion data of Suomi NPP-VIIRS and POI) can quantitatively identify potential central area and multi-layer structure of the city. It fluctuates between 0.2 and 0.6 in the urban core area of Wuhan and between 0.1 and 0.3 in the new town clusters, while in the URF and rural areas drops sharply to below 0.1; (3) the urban-rural fringe area of Wuhan covers a total area of 1482.35 km2, accounting for 17.30% of the total area of the city. Its land use types are mainly construction land, water area, and cultivated land, accounting for 40.75%, 30.03%, and 14.60% of the URF, respectively. Its NDVI and population density are at a medium level, with values of 1.630 and 2556.28 persons/km2, respectively; (4) the double mutation law of NPP and POI in urban and rural space confirms that the URF exists objectively as a regional entity generated in the process of urban expansion, provides empirical support for the theory of urban and rural ternary structure, and has a positive reference value for the allocation of global infrastructure, industrial division, ecological function division, and other researches.

Clinical application of the fracture risk assessment tool in the general population and its correlation with bone turnover markers.

Objective: To compare the risk of osteoporotic fractures between the urban and urban-rural fringe populations in southern China and to explore the effect of bone turnover markers on fracture risk. Methods: Epidemiological investigations were conducted in the urban and urban-rural fringe areas of southern China in June 2018. Residents aged 40years and over who signed informed consent forms were included. Physical examination and questionnaire collection were completed. Bone turnover markers (BTMs) including osteocalcin (OC) and beta cross-linked C-telopeptide of type 1 collagen (β-CTX) were tested. Bone mineral density (BMD) of the femoral neck and lumbar vertebrae 1-4 were measured using dual energy X-ray absorptiometry. Fracture risk assessment tool (FRAX) values were calculated to show the probability of major osteoporotic fracture (PMOF) and probability of hip fracture (PHF) over the next 10years. Results: A total of 1,051 participants were included in this study, including 553 in the urban areas and 498 in the urban-rural fringe areas. The average PMOF and PHF were 3.4 (2.3-5.4) % and .6 (.3-1.5) %, respectively. Compared with that in the urban populations, the femoral neck BMD in the urban-rural fringe populations was lower and FRAX values were generally higher, especially for women. FRAX values in various populations were mainly negatively correlated with lumbar and femoral neck BMD and were positively correlated with β-CTX; meanwhile, only PHF was negatively correlated with OC. After adjusting for sex, elevated β-CTX levels significantly increased the risk of high PMOF in various populations and increased the risk of high PHF in the urban-rural fringe populations. In particular, the risks of increased PMOF and PHF could increase by as much as 33 times and 19.5 times, respectively, in the urban-rural fringe areas. Conclusion: The urban-rural fringe populations in Southern China may be at risk of osteoporotic fracture. In addition to being related to BMD, the FRAX value also correlates with some BTMs. Combining FRAX with BMD, and BTMs may better predict the fracture risk.

Knowledge, attitude and behaviour of general practitioners in Shanghai during the pandemic of COVID-19: a cross-sectional study

ObjectivesTo understand the knowledge, attitude and behaviour of general practitioners (GPs) towards COVID-19 and to provide evidence for improved prevention and control measures against the pandemic.Study designA cross-sectional study was...

Status and Influencing Factors of Hypertension in the Elderly Aged 60 and Above in Mianyang

Objective To understand the prevalence and influencing factors of hypertension among the elderly aged 60 years and above in Mianyang City,Sichuan Province,so as to provide clues for targeted prevention and control of hypertension. Methods A total of 115 775 permanent residents aged 60 and above screened out from Mianyang demonstration sites from October 2017 to April 2019 were investigated by questionnaire and physical examination,and the data of personal basic information,lifestyle,body height,body weight,waist circumference,and blood pressure were collected.SPSS 22.0 was used for descriptive analysis,single factor analysis,and Logistic regression analysis. Results The prevalence rate of hypertension in the elderly aged 60 years and above in Mianyang was 50.60%.Specifically,the prevalence rates of hypertension in men and women were 50.27% and 50.85%,respectively.The prevalence rate of hypertension increased with the increase in age([Formula: see text]=370.199,P<0001).Multivariate Logistic regression analysis showed that the independent risk factors of hypertension included age of 70-79 years(OR=1.327,95%CI=1.292-1.363,P<0.001),the age of 80 years and above(OR=1.455,95%CI=1.386-1.527,P<0.001),widowhood(OR=1.343,95%CI=1.296-1.392,P<0.001),divorce(OR=1.255,95%CI=1.033-1.525,P=0.022),overweight(OR=1.431,95%CI=1.391-1.473,P<0.001),obesity(OR=2.171,95%CI=2.076-2.270,P<0.001),waist-to-height ratio>0.5(OR=1.317,95%CI=1.281-1.354,P<0.001),history of diabetes(OR=1.865,95%CI=1.791-1.941,P<0.001),history of smoking(OR=1.107,95%CI=1.068-1.148,P<0.001),and history of drinking(OR=1.950,95%CI=1.894-2.009,P<0.001).Living in urban-rural fringe areas(OR=0.628,95%CI=0.594-0.664,P<0.001),education background of junior high school and above(OR=0.942,95%CI=0.912-0.974,P<0.001),and low body weight(OR=0.785,95%CI=0.742-0.830,P<0.001) were protective factors for hypertension. Conclusions More than 50% of the elderly aged 60 years and above in Mianyang suffer from hypertension.The elderly with advanced age,widowhood,divorce,overweight,obesity,waist-to-height ratio>0.5,diabetes history,smoking history,and drinking history are the high-risk groups of hypertension.

New sights on the impact of spatial composition of production factors for socioeconomic recovery in the post-epidemic era: a case study of cities in central and eastern China.

The COVID-19 pandemic led to a sharp economic contraction. A comprehensive understanding of the relationship between the spatial composition of production factor (SCPF) and socioeconomic recovery is still missing. Here, we applied the contrasting status of nitrogen dioxide (NO2) concentrations in cities in central and eastern China as natural laboratories. From the perspective of the spatial composition of land (SCL) and the dependence on the inflow population (DIP), four quantifiable indicators (resilience, impact, sensitivity, recovery speed) were used to analyze the adaptability of SCPF to the epidemic lockdown. The results indicate that appropriate SCPF is a prerequisite for a complete “land-population-industry” nexus. The built-up area proportion is below 74.38%, with higher adaptability to epidemic shocks. The range of rural built-up proportion conducive to economic recovery is 10.18%-15.18%. The proportions of various land types inside the city's defense unit should also be constrained. Similarly, DIP is advocated to be maintained below 17.5%. For urban-rural fringe areas, the response to epidemic prevention and socioeconomic recovery are rapid. This observation-driven study indicated that COVID-19 is a shocking reminder for policymakers, to improve the socioeconomic recovery ability from the spatial composition of production factor perspective in the post−COVID−19 era.

Knowledge and behaviour of community residents’ face mask-wearing during the COVID-19 pandemic: a cross-sectional study in Shanghai, China

ObjectivesCOVID-19 is an infectious disease spreading through respiratory droplets. Using a face mask correctly is one of the essential preventive measures. We launched a survey to discover the current face...

Spatiotemporal dynamics of microplastics in an urban river network area

Microplastics contamination in the environment is a global problem, but little is known about their dynamics in urban river networks, an important site of microplastics occurrence and harboring complex transport pathways. In this study, we investigated the spatiotemporal dynamic of microplastics in a typical urban river network in eastern China from December 2018 to September 2019. microplastics abundance (mean ± standard deviation) in the river network ranged from 2.3 ± 1.2 to 104.6 ± 5.6 particles/L and was significantly higher during the wet than during the dry season. The distribution of microplastics in the upper, middle, and lower reaches of the river network did not significantly differ, nor did the abundance of microplastics in the surface water vs. the bottom water. However, high abundances were determined in commercial and industrial areas, at a wastewater treatment plant outlet, in an urban canal, and in an urban-rural fringe area. The seasonal dynamics of the overall abundance of microplastics could be explained by the hysteresis effect of urban plastic production and the variation in regional precipitation. 78.2% of the microplastics were < 330 µm in size; the most common colors were blue and black, and the most common shapes were fragments and fibers. The polymer types of the microplastics were assessed using laser direct infrared (LDIR), a novel chemical imaging system that identified silicone, rubber, polytetrafluoroethylene, and polypropylene as the main components of the microplastics. A non-metric multidimensional scaling analysis (NMDS) based on the abundance of the polymer components across samples showed aggregations of sampling sites, that indicated the possible sources of the microplastics. Our study provides insights into the spatiotemporal dynamics of microplastics in an urban river network and suggests the potential of LDIR in the accurate quantitative analysis of microplastics in the environment.

Investigation and source analysis of bacterial contamination in groundwater in Liuzhou City, China.

Groundwater is an important water source to consider when ensuring the safety of urban water supply. Groundwater contaminated by bacteria poses a potential health risk to the drinking water supply. This study focuses on the water supply of Liuzhou City, a famous industrial city in China. Analyses of the concentrations, spatial distribution, and pollution sources of bacteria in the groundwater were conducted based on samples collected from 27 wells during the wet and dry seasons in 2018. The total colony counts and total coliform were high during both the wet and dry seasons, posing a severe threat to the emergency water supply security for more than one million people in the city. The groundwater in Liuzhou City is generally contaminated by bacteria, with higher pollution levels in the northern urban-rural fringe and central urban areas. Domestic pollution is the main sources of groundwater bacteria. In addition, bacterially contaminated rivers (Liujiang River) passing through the urban area likely transfer bacteria to the groundwater due to the circulation of the groundwater and surface river water. Controlling the bacterial pollution of groundwater in this region requires adherence to a long-term management plan.

Understanding the Diversity of Urban–Rural Fringe Development in a Fast Urbanizing Region of China

The territories between urban and rural areas, also called urban–rural fringe, commonly present inherent instability and notable heterogeneity. However, investigating the multifaceted urban–rural fringe phenomenon based on large-scale identification has yet to be undertaken. In this study, we adopted a handy clustering-based method by incorporating multidimensional urbanization indicators to understand how the urban–rural fringe development vary across space and shift over time in the Yangtze River Delta Urban Agglomeration, China. The results show that (1) the growth magnitude of urban–rural fringe areas was greater than urban areas, whereas their growth rate was remarkably lower. (2) The landscape dynamics of urban–rural fringe varied markedly between fast-developing and slow-developing cities. Peripheral sprawl, inter-urban bridge, and isolated growth were the representative development patterns of urban–rural fringe in this case. (3) Urban–rural fringe development has predominantly occurred where cultivated land is available, and significant inter-provincial differences and tendency shifts have been found in the land cover change processes therein. Our findings indicate that the urban–rural fringe development should be considered as a stage-dependent and place-specific process. This work extends previous knowledge by unraveling the diversity of urban–rural fringe in a fast urbanizing region, and can provide insights into reorienting the spatial planning and land use management within the urban–rural interface.

Epidemiological Characteristics of Hand, Foot, and Mouth Disease Outbreaks in Qingdao, 2009-2018.

Background:In China, hand, foot, and mouth disease (HFMD) outbreaks have become an important issue recent years. We analyzed the epidemiological characteristics of HFMD outbreaks in Qingdao during 2009–2018, and provided evidences for prevention and control of the disease.Methods:Data were analyzed by descriptive analysis and correlation analysis, and throat swabs were detected for enterovirus RNA using RT-PCR.Results:Overall, 116 HFMD outbreaks were reported in Qingdao during 2009–2018, with the epidemic of the outbreaks exhibiting a decreasing tendency. The characteristics of outbreaks presented two patterns, including two-peak pattern and rural area to urban-rural fringe area to urban areas pattern. Male patients were predominant in these outbreaks. The location of the outbreaks changed from nursery to community. Non-EV71/CA16 enteroviruses were gradually becoming predominant enteroviruses serotypes. The durations of outbreaks were positively correlated with response times and the number of cases.Conclusion:The epidemiological characteristics analysis of HFMD outbreaks could provide a scientific basis for the prevention and control the disease. Reporting and handling promptly are the keys to control epidemic outbreaks of HFMD.

A constraint-based approach for identifying the urban–rural fringe of polycentric cities using multi-sourced data

ABSTRACT Studies on urban–rural fringes, which represent regions facing various urbanization problems caused by rapid expansion, have steadily increased in recent years. However, problems persist in the quantitative delimitation of such regions. Based on the characteristics of abrupt urbanization-level changes in urban–rural fringe areas, we propose a constraint-based method in this study to detect the urban–rural fringes of cities with a spatial polycentric structure of ‘Main center–Subcenter’ based on data from multiple sources. We used the proposed approach to delimitate the fringe areas of Jiangyin and Zhangjiagang and identify their urban main center and subcenter pre-defined by their city master plans, towns, and rural hinterlands. Comparison of the identified results of different single urbanization indices, a single detection center, kernel density estimation, and a single constraint revealed that the patch density and Shannon’s diversity index of the proposed method were higher in urban–rural fringes and smaller in city centers and rural hinterlands. This suggests that the landscape of urban–rural fringes delimitated by the proposed method is more fragmented, diverse, and complicated, thereby performing better. This study is significant for future urban spatial analysis, planning, and management.