Obvious Spatial Differentiation Research Articles

Quantifying Spatiotemporal Characteristics and Identifying Influential Factors of Ecosystem Fragmentation in Karst Landscapes: A Comprehensive Analytical Framework

Guanling-Zhenfeng County, a microcosm of the ecologically fragile karst area in southwest China, experiences rapid population growth and urban expansion which intensifies land use transformation and ecological landscape fragmentation. Exploring the spatiotemporal characteristics of landscape fragmentation and its causes in Guanling-Zhenfeng County is of great significance in maintaining the stability of the ecosystem and ecological protection in karst areas. In this study, a comprehensive landscape fragmentation index (FI), geographic probe, multi-scale geographically weighted regression (MGWR), and PLUS model were used to quantitatively explore the spatiotemporal characteristic heterogeneity, causes, and future scenario projections of landscape fragmentation in Guanling-Zhenfeng County from 2000 to 2020. The results showed that: (1) the distribution of each landscape index was characterized by obvious spatial differentiation. Among them, the spatial distribution trends of patch density (PD) and largest patch index (LPI) were opposite and the distribution trends of Shannon diversity index (SHDI) and Shannon evenness index (SHEI) were similar. There were fewer heterogeneous patches in the study area from 2000 to 2020, and the landscape shape was more regular and less fragmented. (2) The overall landscape fragmentation in Guanling-Zhenfeng County from 2000 to 2020 was dominated by moderate fragmentation, with the smallest percentage of extreme fragmentation, and heavy fragmentation was mainly distributed in the north-central part of the study area. (3) Natural and social factors jointly affect the landscape fragmentation in Guanling-Zhenfeng County, and there is a significant interactive enhancement effect among the factors, with population density being the most important influence factor. In addition, the effects of the factors on landscape fragmentation showed significant spatial non-stationarity. (4) The characteristics of landscape fragmentation changes in Guanling-Zhenfeng County under different scenarios varied significantly, with the largest percentage of increase in heavy landscape fragmentation under the business-as-usual scenario (BAU), the next under the land use planning scenario (LUP), and the smallest under the ecological protection scenario (ESP).

The spatial and temporal situation of China's digital technology innovation and its influencing factors.

Digital technology innovation is the core driving force for the high-quality development of the digital economy, and in-depth exploration of the regional distribution pattern and formation mechanism of digital technology innovation in China is conducive to the rational layout and coordinated development of the inter-provincial digital economy. Based on the Reference Relationship Table of the Classification of Core Industries of Digital Economy and the International Patent Classification (2023), the patent authorization data of digital technology from 2012 to 2022 were obtained, and the spatiotemporal situation of China's digital technology innovation was analyzed by using ArcGIS software, Dagum's Gini coefficient, and Moran's I index, and the spatial Dubin panel model was used to explore the influencing factors of digital technology innovation. It is found that: (1) the scale and vitality of China's digital technology innovation have increased significantly, and there are obvious spatial differentiation characteristics, and the innovation level of "eastern coastal-central and western interior" is decreasing, forming a cluster distribution pattern in the Yangtze River Delta region, Beijing, Guangdong, and other places, and the degree of agglomeration is decreasing. (2) The overall regional differences in China's digital technology innovation are large, the differences between the East and the West dominate the interregional differences, and the net differences between regions are the main factors leading to regional differences. (3) There is a significant positive spatial correlation between the scale and vitality of digital technology innovation, which has a significant spatial spillover effect. (4) The results confirm that the level of economic development, digital access, financial scientific and technological support, technology market development level, and R&D intensity have a significant positive impact on the scale and vitality of digital technology innovation; The investment in scientific and technological talents has a significant positive impact on the scale of digital technology innovation, but has no significant impact on the vitality of digital technology innovation.

Quantification of Nitrate Sources and Its Spatial Heterogeneity by Dual Isotopes

Nitrate source allocation is important for watershed environmental management. In this paper, 59 surface water samples were collected in late July 2022 in the Erhai Basin of the Yunnan–Guizhou Plateau in southwestern China, where the source of nitrate pollution in surface water is still unknown. The potential sources of nitrate were identified and estimated using hydrochemistry indicators, the δ 15 N / δ 18 O − NO 3 − and the Stable Isotope Analysis in R (SIAR) model. The results showed that the various forms of nitrogen compounds, transport and transformation processes, and their sources in the Erhai Basin were characterized by obvious spatial scale differentiation. First, the mean values of NO 3 − , NO 2 − , and NH 4 + in the watershed were 1.14 ± 1.49 mg/l, 0.11 ± 0.06 mg/l, and 0.14 ± 0.09 mg/l, respectively, while the differences among the three in the secondary zoning scale were mainly reflected in the ES region. Second, both δ 15 N − NO 3 − (−0.64‰ to +17.67‰) and δ 18 O − NO 3 − (−1.87‰ to +24.42‰) had some differences in primary and secondary zoning. Third, nitrification was the dominant process of nitrate transport and transformation in the watershed, but it was also characterized by spatial differentiation. Fourth, the output of the SIAR model showed that the proportion of nitrate pollution sources in the basin was soil nitrogen (37.16%), domestic sewage (36.06%), livestock manure (13.49%), and chemical fertilizer (13.29%), and there was also obvious spatial differentiation. This study provides a new perspective for the spatial heterogeneity analysis of nitrate pollution sources and the corresponding pollution control.

Supply-demand relationship and spatial flow of urban cultural ecosystem services: The case of Shenzhen, China

Cultural ecosystem services (CES) have garnered significant attention due to their capacity to comprehensively evaluate the influence of ecosystem degradation on human well-being. It is very important to evaluate the spatial coordination relationship between the supply and demand of urban CES and explore its spatial flow mechanism for guiding the sustainable development of urban regions. However, research on the relationship between supply and demand of urban CES and their spatial flows is still in the conceptual exploration stage, and its quantitative assessment methods are not yet mature. Taking Shenzhen as an example, this study uses the Social Values for Ecosystem Services model to evaluate the supply of CES based on environmental background and survey statistics; Uses the topic model of natural language processing, quantify the demand of CES based on social media data. The Bivariate Local Indicators of Spatial Association index is utilized to examine the correlation between supply and demand, while a crowd activity extraction method based on mobile phone signaling data is developed to simulate the spatial flow pattern of CES. The results show that: (1) The supply of urban CES shows obvious spatial differentiation; There are differences in the perception of the needs of various CES. Among them, the beneficiaries have higher needs for Aesthetic and Recreation. (2) The relationship between supply and demand of urban CES shows different degrees of spatial mismatch, with the proportion of the supply-demand matching area to the total area being less than 20%, and the main type of supply-demand mismatch being low supply-high demand. (3) All kinds of CES flow from the center of the study area to the east, among which the flow of recreation and Aesthetic is more active, with the highest flow of 189.7 and 135.3, respectively. Overall, the coordination between various types of CES in the region is still insufficient. We should encourage the establishment and improvement of a diversified transportation system connecting the central urban area and other regions while enhancing the condition of the local ecological conditions, to improve the capacity of urban ring roads and rail transit, to promote the sustainable development of the regional ecological environment and social economy, and to enhance human well-being.

Seismic geomorphology analysis and petroleum geology significance of presalt Jurassic carbonate in the right bank of Amu Darya River

Paleogeomorphological pattern has a great influence on the formation of carbonate reef-shoal complexes and the evolution of carbonate reservoirs. Accurate paleogeomorphology restoration is one of the significant tasks while exploring oil and gas stored in carbonate rocks. However, the previous paleogeomorphology restoration methods mostly rely on high-density drilling data or high-quality seismic data. The applicability of these methods to areas with low-quality seismic data of presalt reservoirs and less drilling control is often low, and they cannot accurately restore paleogeomorphology. This will seriously affect the success rate of oil and gas exploration in presalt reservoirs. Hence, this study aims to address the problem associated with paleogeomorphology restoration under the conditions of highly flexible salt-gypsum rock and low-quality seismic data. By comparing the paleogeomorphology restoration principles of the impression and residual thickness methods and considering multiple factors such as sediment filling and tectonic evolution settings, an innovative model representing the relationship between geomorphology and seismic attributes was established and the paleogeomorphology in the period of deposition of the Middle Jurassic Callovian strata in the eastern part of the right bank of Amu Darya River was restored based on seismic geomorphology, 3D seismic data, drilling data, well log data, core data, and thin-section data. Based on the analysis of the reconstructed paleogeomorphology, it is observed that the high paleogeomorphology shoals in the western part of the study area obstruct the growth of the eastern shoals, affecting the development thickness. However, the quality of thin-layered shoal reservoirs in the eastern part is superior to those in the western part. The distribution of well-developed thick shoals and high-quality reservoirs in this area exhibits obvious spatial differentiation on the plane. Under the unique paleogeomorphology pattern of alternate uplifts and depressions in this area, the quality of reservoirs in the western part is poor, the development quality of reef-shoal reservoirs in the central and eastern region is superior, and the reservoirs in the paleogeomorphologic lowlands are poorly developed.

Assessing Habitat Quality and Identifying Influencing Factors in the Township Areas of Dawen River Basin

Dawen River is the development center of the ancient cultural region in Shandong. It is of great significance for the protection, inheritance and development of the basin civilization to study the quality of the habitat in the river basin. This paper builds ecosystem ternary model of habitat quality, using the InVEST model to evaluate the habitat quality of the river basin in 2020, combined with the spatial correlation model to explore the spatial characteristics, and the influence of habitat quality, habitat degradation of nine factors for exploratory regression, is divided into social factors, economic factors and natural factors for analysis. The results show that:(1) The habitat quality in Dawen River Basin varies greatly, showing habitat fragmentation and obvious spatial differentiation; (2) the habitat quality in Dawen River Basin shows an obvious trend of degradation, and the areas with high habitat degradation occupy most of the basin, showing an expansion trend of point-line-surface; (3) social factors, economic factors and natural factors have different effects on habitat quality and habitat degradation, and the influence of land development intensity is most significant. The results provide guidance for the politics of ecological protection in the Dawen River Basin.

Spatial Layout Analysis and Evaluation of Electric Vehicle Charging Infrastructure in Chongqing

This study considers the spatial analysis and evaluation layout of electric vehicle charging infrastructures, taking the central urban area of Chongqing as an example. Mathematical model analysis, ArcGIS spatial analysis, field investigation, questionnaire measurement, and hierarchical analysis methods are utilized to discuss the current distribution characteristics and supply–demand matching of the electric vehicle charging infrastructure in this region. The resulting data can provide references for the optimal layout of charging infrastructure. The main conclusions of this study are as follows: (1) The configuration and demand of charging infrastructure in the central urban area of Chongqing have obvious spatial differentiation and show strong centrality. (2) It is a common phenomenon that the charging infrastructure in the central urban area of Chongqing is in short supply, and it is pressing that a new charging infrastructure be built. (3) In the process of construction and operation of charging infrastructure, various factors, such as economy and traffic, should be comprehensively considered; at the same time, incidents of inefficient operation, such as being crowded out by nonelectric vehicles and unmaintained facility failure, should be minimized.

The impact of poverty alleviation policies on rural economic resilience in impoverished areas: A case study of Lankao County, China

It has been recognized that China's targeted poverty alleviation policy can greatly improve the economic development of rural areas, but whether it can improve rural resilience for sustainable development has been less studied. Based on anatomising the connotation of rural economic resilience and proposing theoretical framework for the influence of policies, this study empirically analyses the implication of poverty alleviation policies on rural economic resilience using regression analysis techniques, based on field survey data from 338 villages in Lankao County, China. It is shown that rural economic resilience is connected with their resistance, adaptation, and transformation capabilities, and China's targeted poverty alleviation policies have significantly improved the economic resilience of villages because of the government's efforts to upgrade production factors, optimise the economic structure and expand rural functions have awakened the impetus of endogenous development in rural areas. Compared with resistance and transformability, poverty alleviation policies have a greater positive impact on the adaptability of rural economies. The explanatory power of poverty alleviation policies on the rural economic resilience of Lankao County shows obvious spatial differentiation. The effectiveness of poverty alleviation policies was more prominent in the southeast, where poverty was worse. The recommendations proposed based on these results can provide an important reference for promoting rural economic resilience and sustainable development in developing countries.

Correlation between Distribution of Rural Settlements and Topography in Plateau-Mountain Area: A Study of Yunnan Province, China

Topography is one of the important factors influencing the distribution of rural settlements, as the natural environment in plateau-mountain areas is more complicated and harsher and the forces of various natural influences are more obvious. Analyzing the correlation between settlement distribution and topography would help understand the influence of topography on human activities. This paper takes rural settlements in Yunnan Province as the research object, introduces the concept of the distribution index, and integrates the methods of GIS spatial analysis and mathematical statistics to analyze the correlation between them. The results show that (1) the distribution pattern of rural settlements in Yunnan Province is dense in the northeast, sparse in the northwest, dense in the middle, and sparse in the south; the overall pattern shows low density, fragmentation, and a dotted distribution of high-value areas, showing three typical core areas with very obvious spatial differentiation. (2) The distribution of rural settlements is influenced by three key topographic factors: Relief amplitude, incision depth, and surface roughness. The dispersion index of rural settlements drastically declines as the value rises. (3) Each topographic factor influences the natural resources and climatic characteristics of the region, and by coupling them with the production and life of the rural settlements and the psychological needs of the inhabitants, they form an intrinsic mechanism that influences the distribution of rural settlements. (4) Topography is an important factor when developing and constructing in plateau-mountain areas. The environmental protection and construction of human settlements should be in accordance with nature and adapted to the terrain, which can reduce the damage to the natural environment. The study provides effective data support for quantifying the relationship between the distribution of rural settlements and topography in the plateau-mountain area and optimizing the layout of rural settlements.

Environmental Adaptation in the Process of Human-Land Relationship in Southeast China's Ethnic Minority Areas and Its Significance on Sustainable Development.

The relationship between regional human development and geographic environment is the basis for dynamic social change, and studying the evolution of human-land relations in typical regions can provide background knowledge for global change studies. This study is based on GIS and spatio-temporal statistical techniques, combined with the analysis of toponymic cultural landscapes, to study ethnic minority regions of southeastern China. The results show that: (1) The geographical environment of the region will affect the naming of villages, and the orientation and family name are the most common; the frequency of plants, pit (keng), animals, and flat (ping) is also very high. (2) Han settlements and She settlements have obvious spatial differentiation, and in general the Han distribution area is lower than that of the She. Han settlements are mainly distributed in plain areas along rivers with elevations less than 200 m; She settlements are mainly distributed in hilly areas (200~500 m) and low mountain areas (500~800 m). (3) The results of quadrat analysis and nearest neighbor index analysis show that both Han and She settlements are clustered in the spatial distribution pattern, and the distribution of She settlements is more clustered than that of Han, with more dense settlements at a certain spatial scale. The regional cultural landscape is the result of the development and evolution of human-land relationship, and the comprehensive analysis of cultural landscape can understand the process of human-land relationship in a small region. The settlements in the region are indicative of the geographic environment in terms of village naming, spatial pattern, elevation differentiation and relationship with rivers, which can reflect the environmental adaptation process of human activities.

Quantitative Analysis of the Contributions of Climatic and Anthropogenic Factors to the Variation in Net Primary Productivity, China

Accurate quantification of the contributions of climatic and anthropogenic factors to the variation in NPP is critical for elucidating the relevant driving mechanisms. In this study, the spatiotemporal variation in net primary productivity (NPP) in China during 2000–2020, the interactive effects of climatic and anthropogenic factors on NPP and the optimal characteristics of driving forces were explored. Our results indicate that NPP had obvious spatial differentiation, an overall increasing trend was identified and this trend will continue in the future for more than half of the pixels. Land use and Land cover and precipitation were the main factors regulating NPP variation at both the national scale and the sub-region scale, except in southwest China, which was dominated by altitude and temperature. Moreover, an interactive effect between each pair of factors was observed and the effect of any pair of driving factors was greater than that of any single factor, manifested as either bivariate enhancement or nonlinear enhancement. Furthermore, the responses and optimal characteristics of NPP concerning driving forces were diverse. The findings provide a critical understanding of the impacts of driving forces on NPP and could help to create optimal conditions for vegetation growth to mitigate and adapt to climate changes.

From accessibility of traffic to accessibility of service: the spatial analysis of N-minute service circle of urban park system

ABSTRACT As an important strategy of basic public services in China, service “accessibility” follows the concept of fair and equal public services. Compared with the traditional transportation accessibility, it is also a comprehensive consideration from the dimension of residents’ demand and service supply to promote the balance of urban park space layout and service coverage. Based on the N-minute service circle, this study establishes a comprehensive evaluation index system to quantitatively assess the service balance of urban parks based on three dimensions of service availability, spatial balance and social equity, taking the Shangcheng District of Hangzhou as an example. And further, an optimization model of urban park system is constructed to carry out spatial analysis and optimal adaptation of urban park system by combining residents’ demand and evaluation. The results show that the overall accessibility of urban park services shows a spatial pattern of “high in the north and low in the middle”, with obvious spatial differentiation along the river area. The urban park system optimized by the model based on the assessment results achieves the “accessibility” and “refined” quality of urban park services. Meanwhile, this study provides a reference for building a more all-age and quality urban park system.

Location Choice of the Five Mekong Countries’ Ability to Undertake China’s Industrial Transfer

The core of “building a community of destiny of the Mekong countries” is to promote sustainable economic development in the Mekong basin, and a comprehensive understanding of the ability of the five Mekong countries to take over Chinese industries is of great significance to promote Mekong cooperation. The study analyzes the overall take-up capacity of the five Mekong countries by constructing an index system for evaluating the take-up capacity of industries. The study shows that the industrial transfer capacity of the five Lan Mekong countries from 2011 to 2017 shows a stable trend, with Vietnam declining slowly and Laos growing faster, and the industrial transfer capacity of the five countries shows obvious spatial differentiation characteristics.

CHARACTERISTICS AND DRIVING FACTORS OF REGIONAL ECONOMY COORDINATED DEVELOPMENT EFFICIENCY UNDER URBAN DIGITALIZATION: EVIDENCE FROM THE YANGTZE RIVER ECONOMIC BELT

Regional economy coordinated development (RECD) is an important symbol of social progress and an important guarantee of social harmony, political stability and economic sustainable development. Previous studies mainly focus on the relationship between digitalization and RECD, but they fail to investigate the RECD efficiency (RECDE) driven by urban digitalization. This paper characterizes and explores the RECDE in the Yangtze River Economic Belt (YREB) from 2011 to 2019 from the perspective of urban digitalization by constructing a novel evaluation indicator system and using an EBM model. Meanwhile, this paper analyses the regional differences, temporal–spatial evolution characteristics, and the influencing factors of urban digitalization driving RECDE via the methods of spatial autocorrelation, the Gini coefficient, kernel density estimation and a geo-detector. The results indicate that: (1) the RECDE of YREB is on the rise as a whole, but the efficiency level is low. The RECDE shows a stepwise increase in the order of upper, middle and lower reaches. The RECDE also shows obvious spatial differentiation characteristics. (2) From the perspective of temporal and spatial evolution, the RECDE has changed from a dispersed state to a contiguous agglomerated state as a whole. The average RECDE of the YREB has varied significantly over the years. High-efficiency cities are relatively dispersed, while low-efficiency cities are relatively concentrated. (3) Government intervention, physical capital level and economic development level are the primary influencing factors of RECDE. These results imply that the government should attach great importance to the role of digitalization in improving the RECDE. When formulating regional coordinated development policies, the government should first formulate differentiation strategies according to the economic development level of different cities, and then give full play to the promoting role of government intervention and digital capital investment.

Multi-Scale Spatiotemporal Variations and Drivers of PM2.5 in Beijing-Tianjin-Hebei from 2015 to 2020

Understanding the spatiotemporal heterogeneity and complex drivers of PM2.5 concentration variations has important scientific value for sustainable urban development. Taking Beijing-Tianjin-Hebei (BTH) as the research area, and using spatial analysis techniques and wavelet methods to explore the spatiotemporal heterogeneity of variations in PM2.5 concentrations, the research shows that in the past six years (2015–2020), the PM2.5 concentrations in the BTH area have a downward trend, and the mean is 59.41 μg/m3; however, the distribution pattern of PM2.5 pollution has changed very little, and the concentration in the south and southwest is still generally high. The continuous wavelet transform revealed that the PM2.5 concentrations in the study area have a short period of about a week to a half a month and a long period dominated by annual cycle. The effect of a single meteorological factor on PM2.5 concentrations is weak, but this effect has obvious spatial differentiation characteristics from coastal to inland and has a double-sided effect due to different geographical locations. The wavelet transform coherence revealed that dewpoint temperature at 2 m (TED), meridional wind at 10 m (WV) and air temperature at 2 m (TEM) are important single meteorological factors that affect the variation of PM2.5 concentrations. The multiple wavelet coherence reveals that in scenarios where two meteorological factors are combined, the combination of TED-mean wind speed (WS) is the best combination to explain the variation in PM2.5 concentrations (AWC = 0.77, PASC = 41%). In the combination of three meteorological factors, TEM-WV-WS explained the variations of PM2.5 concentrations in the BTH region to the greatest degree (AWC = 0.89, PASC = 45%). Finally, the research shows that the variations of PM2.5 concentrations in the BTH region can be better explained by a combination of 2–3 meteorological factors, among which temperature and wind are the key meteorological factors. This research will provide a new window for the multi-scale variation characteristics and multi-factor control relationship of PM2.5 concentrations in the BTH region and provide a new insight for the prevention and control of air pollution.

Evaluation of Suitability and Spatial Distribution of Rural Settlements in the Karst Mountainous Area of China

With the acceleration of urbanization and the implementation of the rural revitalization strategy, the spatial pattern of rural settlements in China has changed significantly. The suitability of rural settlements is a requirement for rural revitalization. The objective of this paper is to quantitatively depict, analyze, and evaluate the suitability of rural settlements in karst mountain areas to eliminate poverty and accelerate the process of new urbanization by constructing rural settlements. Taking 525 rural settlements in Songtao Miao Autonomous County, Guizhou Province, in the karst mountainous area as the research object, the distribution of rural settlements is studied using point mode spatial analysis and neighborhood analysis. The impacts of natural and regional environmental factors are detected using Geodetector. To make the evaluation results more scientific and reasonable, a suitability evaluation model based on Geodetector and AHP was constructed to solve the subjective problem of the weight assignment of the AHP method and reflect the interaction between the influencing factors. The results demonstrate the following. (1) The variation coefficient of the Thiessen polygon area in the Voronoi diagram shows that the spatial distribution of rural settlements is mainly random. The spatial distribution of kernel density in rural settlements presents multiple nuclear centers, with obvious spatial differentiation, with Changping Township being the densest and Waxi Township the sparsest. (2) Rural settlements are mainly distributed below a 15° slope, 800 m above sea level, within 6 km from rivers, 4 km from roads, and 7 km from the township center. Slope and distance from the river are the main driving forces of spatial differentiation. The spatial distribution of rural settlement areas is affected by natural and regional environmental factors, and the interaction between slope and distance from the river is the strongest explanatory power. (3) The results of suitability evaluation show that 87.40% of the rural settlement areas are categorized as “suitable” and “relatively suitable” for living. The “suitable” rural settlement areas are mainly concentrated in the hilly and low mountain areas and river valleys, with relatively gentle terrain in the middle and east, distributed in two north–south trending strips. The “relatively suitable” rural settlements are mainly scattered in the surrounding livable areas. This study could provide a reference for the planning and reconstruction of rural residential areas in karst mountain areas and expand the research means of suitability evaluation of rural residential areas, and it is applicable to other settings.

Spatial differentiation and factors influencing the benefits of industrial poverty alleviation in villages

AbstractIndustrial poverty alleviation is one of the most important aspects of targeted poverty alleviation. Identifying the mechanism influencing the spatial differentiation of the benefits of industrial poverty alleviation plays an essential role in optimising an industrial layout for poverty alleviation, consolidating poverty alleviation achievements, and revitalising rural industries. This study examined the spatial distribution characteristics and influencing factors of the benefits of industrial poverty alleviation at the village level using the household data collected from Jiangjin District, Chongqing, China. The results show that the benefits of industrial poverty alleviation presented obvious spatial differentiation in the villages with the overall performance being high in the north and low in the south and decreasing from the south of the county to the north and south. Spatially, there was a significant positively correlated agglomeration effect. High‐value agglomeration areas were concentrated in the north with the characteristics of ‘one centre and two subcentres’. However, low‐value and outlier agglomeration effects were not obvious, presenting sporadic distribution. Seven major factors affect industrial poverty alleviation in Jiangjin District, including average altitude and land transfer rate. The interaction between any two of the seven factors has a more significant impact than that of a single factor.

Identifying the Influencing Factors of Cooling Effect of Urban Blue Infrastructure Using the Geodetector Model

The urban heat island (UHI) effect has a serious negative impact on urban ecosystems and human well-being. Mitigating UHI through nature-based methods is highly recommended. The cooling effect of urban blue infrastructure (UBI) can significantly alleviate the effects of UHI. Revealing the crucial influencing factors of the cooling effect of UBI is of great significance for mitigating the UHI effect. In this study, the water-cooling intensity (WCI) and water-cooling range (WCR) were used to quantitatively analyze the cooling effect of UBI in Hefei city in summer. Furthermore, the influencing factors and their interactions with the cooling effect of UBI were investigated based on the Geodetector model. The results revealed that: (1) The surface thermal environment of the built-up area of Hefei presented obvious spatial differentiation characteristics. (2) There were nine influencing factors that significantly influenced the WCI variation, with the greatest influencing factor of road density. In contrast, only the landscape shape index had a significant effect on WCR variation. (3) The interaction of environmental characteristics, water body characteristics, and socioeconomic characteristics had a significant influence on the cooling effect of UBI, and the interaction relationship between the influencing factors was mutually enhanced. The findings from our research can provide a theoretical reference and practical guidance for the protection, restoration, and planning of UBI as a nature-based solution to improve the urban thermal environment.

Spatial Accessibility of Multiple Facilities for Affordable Housing Neighborhoods in Harbin, China

The spatial mismatch between affordable housing neighborhoods and public services/facilities significantly reduces the well-being of low-income dwellers, which has risen to a typical issue of spatial injustice. Previous studies on accessibility evaluation most focus on a single type of service, lacking empirical studies exploring the integrated spatial accessibility of multiple services for low-income residents. Taking Harbin City in northeast China as an example, this study assessed the spatial accessibility of transit, education, healthcare, shopping, and recreation facilities for affordable housing neighborhoods, using the Gaussian-based 2SFCA method. The pattern of accessibility for each type of facility in Harbin showed obvious spatial differentiation between the urban core and the city periphery, for both affordable housing neighborhoods and other neighborhoods. The sample household survey indicated that low-income households who were generally characterized as elderly, less-educated, under-employed or unemployed had extremely restricted and passive residence choices. In comparison to non-low-income households, the spatial accessibility of higher-level facilities for low-income households was relatively poorer. Particularly, affordable housing neighborhoods had much lower accessibility of subway stations, though more than 97% of low-income respondents living in affordable housing neighborhoods chose to solve the daily trip demand by taking a bus or the subway. With respect to equity-oriented urban planning, more importance should be attached to the spatial accessibility of public services and facilities when planning affordable housing projects for low-income households.

Ecosystem Service Value Evolution and Security Pattern Optimization in Huaihai Economic Zone

The ecological and environmental effects caused by land use change have attracted global attention. Huaihai Economic Zone, as the core of the Huaihe River ecological economic belt, has experienced a reciprocal evolution of land use, ecological security and regional economic development. Based on multi-stage land use data extracted by Google Earth Engine (GEE), the spatio-temporal differentiation characteristics of ecosystem service value (ESV) evolution in Huaihai Economic Zone from 1998 to 2018 were analyzed with the help of ESV assessment and a minimum accumulated resistance model (MCR), and the regional ecological security pattern (ESP) was optimized. The results show that ESV intensity has obvious spatial differentiation, which is higher in northeastern China and lower in southwestern China. The median ESV area accounted for the largest proportion, while the high and low ESV areas accounted for a small proportion. The characteristics of EVS temporal and spatial differentiation show decreasing and increasing grades. From the perspective of development period, the ESV grade changes show a positive trend. In the optimization of the ecological security pattern, 26 important ecological sources, 22 main landscape ecological corridors, and 65 ecological strategic nodes were optimized and identified, and the middle-level ecological security zone accounted for the largest proportion. The main reasons for the changes in the ESV and ESP are closely related to the changes in local natural resources and the changes and adjustments in government protection policies. These research results can provide a reference for inter-provincial territorial space protection and the formulation of a sustainable development strategy.