As a crime that threatens public safety and social stability, child trafficking has attracted widespread attention from all sectors of society. Few studies have been conducted on child trafficking, especially in the literature review conducted from the perspective of comparison between China and abroad, which makes it difficult to fully reveal the system and development of current research. This study clarifies the thematic structure and development of child trafficking in China and abroad, based on the "Web of ScienceTM Core Collection" and CNKI data sources, using CiteSpace software. Specifically, the study comparatively examines the progress of child trafficking studies in China and abroad since 2000 and analyzes future development trends from the time of publication, regional and subject distribution, research institutions, and keyword co-occurrence. We hope that this work provides a relatively complete and objective understanding for innovative future research. The results indicate that: (1) the research on child trafficking started earlier abroad, and the theoretical system and research methods are relatively mature. From 2000 to 2020, a total of 215 articles were published in Web of Science, showing two stages of fluctuating and rapid growth, and USA ranks first worldwide. There are 46 core articles published in CNKI, showing two stages of initial exploration and fluctuating growth overall, with a relatively slow growth rate in China. More studies are distributed in the fields of social studies, psychology, pediatrics, family studies and criminology in abroad, while domestic studies are mainly distributed in the field of law, criminology and sociology. In recent years, the research in the field of geography has risen rapidly, and there is ample room for development. (2) Due to the differences in regional environment and national conditions, international child trafficking is part of a study on human trafficking, which is mainly for the purpose of exploitation, including direct and indirect exploitation, involving various topics such as commercial sexual exploitation, labor exploitation, trafficking human organs, child marriage trafficking, and other types of trafficking. Commercial trafficking and sexual exploitation are the main research hotspots of child trafficking. Child trafficking in China is usually discussed in combination with the trafficking of women, focusing on the provincial trafficking for the purpose of adoption, and "family control" and "lured adoption" are common ways of committing crimes. The legal policy and social reasons surrounding child trafficking are hot topics of concern. (3) With the increase in interdisciplinary integration, child trafficking involves suicide risk and well-being, rehabilitation and return to society, child protection and trafficking prevention and control measures, which have become popular topics abroad. The theme of domestic child trafficking has extended from focusing on legal policies and social reasons to spatial-temporal patterns, influencing factors, resettlement, and social integration. In the future, how to integrate the relevant parties involved in child trafficking (criminals, victims or guardians, and other people) with the spatio-temporal environment (social environment, built environment, and surrounding people flow environment), and explore the evolution of geographical factors and the spatio-temporal activity trajectory of child trafficking from the perspective of criminal geography? It is important to deeply analyze the occurrence mechanism of child trafficking from the interactive perspective of time, space, and humans. How to make full use of the modern technological means to track and combat child trafficking in practice, to contribute to the prevention and management of this issue at home and abroad, constitutes a key question.

Cultural memory is a spiritual, inner, and middle world composed of self-consciousness, memory, and behavior that expresses the cultural phenomenon, local emotions, and identity generated by human practice in the present world space. Geography pays more attention to the human-land relationship and spatial perception in the formation of cultural memory and constructs a unique cultural memory space. This space is the agglomeration of figurative cultural relics in space, as well as the spiritual representation of non-figurative places, such as art, text, and folklore in space. By systematically analyzing the theory of cultural memory, this study summarizes the process of evolution and development context of cultural memory. Based on 1,527 key domestic and international studies on geography, this study analyzes the main content and progress of global cultural memory space research from the perspective of keyword co-occurrence clustering, theme path evolution, and research trend, with the assistance of CiteSpace—the bibliometrics and visualization tool. By reviewing the frontier hot spots of cultural memory space research at home and abroad, this study aims to construct a research paradigm of cultural memory from the perspective of geography, improve the research methods of cultural memory, and provide a reference for the local application and multidisciplinary integration of cultural memory theory. The analysis results focus the research topics of foreign cultural memory space primarily on: 1) the memory representation of the landscape of daily life; and 2) political and ritual studies in memory. Domestic research topics primarily include: 1) cultural and local studies in collective and social memory; 2) research on urban and rural memory carried by space; and 3) research on heritage memory reproduction, promoted by cultural tourism. The literature on cultural memory space at home and abroad has gradually increased in recent years, as has the attention paid to memorial landscape, heritage buildings, ritual celebrations, war trauma, and national memory; however, the research on cultural memory space has not formed a specific theoretical paradigm. Most of the literature only focuses on the integration of cultural memory and other fields, and relatively few studies address the connotation of cultural memory space, media conversion mechanisms, and spatial identification methods. The perspective of the content and trends in domestic and foreign research indicates that Western scholars pay more attention to the study of migration, rights, free will, women, power politics, and war trauma. The focus on space is mainly on cities, emotions, and rights. Domestic geographers focus on deconstructing regionalized and China-seized cultural memory and local identity from the intangible carrier of memory. Most studies are based on obvious policy orientations. War sites, red tourist sites, traditional villages, characteristic folk customs, and festival ceremonies have become important themes in the study of cultural memory space. In the future, geography research should depict the practical process of text, ritual, and language through non-representational means and re-introduce memory into human research in a materialized way. Simultaneously, the connotation of urban and rural cultural memory should be clearly defined, and heritage, immigration, and tourism should be adopted as the new themes of cultural memory space research through digital images.

The Belt and Road Initiative aims to achieve common development and prosperity for all countries. Building a scientific and reasonable geopolitical risk assessment system is an important prerequisite for participating countries to prevent and resolve geopolitical risk. Taking 64 countries in the six economic corridors of the Belt and Road Initiative as the assessment object, this study builds a geopolitical risk assessment system based on post-transaction costs. It analyzes the geopolitical risk level, spatial and temporal distribution characteristics, and influencing factors using the full array polygon graphical indicator method, Global Moran's I, and the spatial Durbin model. The research results show that: 1) From the time dimension, the geopolitical risks of participating countries show a trend of first rising and then falling, reaching a peak in 2015. 2) From the perspective of spatial distribution, high-risk areas are mainly concentrated in the Middle East and South Asia, while medium to high risk areas are concentrated in Indochina and the Arabian Peninsula. Most of the low to medium risk countries are Western Pacific island countries, while low-risk countries are mainly in Central Europe. The clustering characteristics of geopolitical risks are obvious. The results of Global Moran's I show that from 2011-2020, the geopolitical risk concentration area was initially located in the Middle East and South Asia, and then in 2015, Europe and East Asia also experienced high geopolitical risks. By 2020, it was still mainly concentrated in the Middle East and Eastern Europe, however, generally, the regions with high geopolitical risk will still be mainly concentrated in the Middle East and Eastern Europe. 3) The research results on the factors influencing geopolitical risks indicate that political stability, economic freedom, economic growth, increased education expenditure, and better natural resources have a significant inhibitory effect on geopolitical risk, while increases in the unemployment rate, population size, and oil resources, will to some extent, promote the generation of geopolitical risks. The indirect effect results show that political stability, economic freedom, and the unemployment rate of the host country have a significant impact on surrounding countries. Based on this, we believe that countries participating in the Belt and Road Initiative need to improve their government governance capabilities, accelerate their modernization transformation, effectively utilize the resources, funds, and technologies brought about by the Belt and Road Initiative. Furthermore, actively integrate into the regional economic cooperation framework of the Belt and Road Initiative and improve their ability to manage geopolitical risks. This study enriched the evaluation system of geopolitical risks. During the construction of the evaluation indicators, the results emphasized the sudden and violent characteristics of geopolitical risks, further explained the violent confrontation and economic game existing in geopolitical risks, and effectively enriched the literature on the spatial characteristics and influencing factors of geopolitical risks of countries participating in the Belt and Road Initiative. It should be pointed out that there are still some limitations in this study. This study is based on countries participating in the Belt and Road Initiative and there are deficiencies in the discussion of geopolitical risk for countries not in the region. Future research can be based on a global perspective, further enriching the evaluation index system of geopolitical risk, and conducting more in-depth research on the spatial transmission path and geopolitical risk avoidance measures.

The prediction of rainstorms and floods in small and medium-sized watersheds, as well as the synthesis of related parameters, plays a pivotal role in preventing flood disasters. Environmental changes have led to an increase in hydrological extremes such as rainstorms and floods, presenting unprecedented challenges for small and medium-sized river basins. In this review, we systematically categorize, and summarize the processes involved in predicting rainstorms and floods in these watersheds, along with advancements in correlated parameter synthesis research. Furthermore, we analyze and discuss the most commonly employed runoff and confluence estimation methods and their associated parameters in practical applications, as well as their limitations. First, we establish the concept of small- and medium-sized watersheds across various academic disciplines. From a hydrological perspective, these watersheds typically exhibit slope confluence and have relatively small catchment areas. In terms of eco-hydrology, the ecological water demand of the basin must be calculated based on the different communities occupying the river basin and divided by area according to the ecological samples from each district after the investigation. Thereafter, we summarized the methods and types of runoff calculation and parameter synthesis in small- and medium-sized basins, and the methods and principles of runoff analysis, such as rainfall–runoff correlation diagram, infiltration curve method, deduction method, runoff coefficient method, and hydrological model method as well as the methods of parameter synthesis, such as rainfall-runoff correlation diagrams and loss methods are introduced. Second, we summarize and discuss the assessment of confluence and its associated parameters in small- and medium-sized river basins. This encompasses background information and various calculation methods, such as the instantaneous unit line, comprehensive unit line, inference formula method, and empirical formula method. We also examine how the three major elements of parameter synthesis convergence influence confluence parameters. We emphasize that combining radar rainfall measurements, high-resolution remote sensing, high-performance computing, and deep learning can facilitate research on simulating and forecasting rainstorms and flood processes in small- and medium-sized basins. However, a significant portion of these basins lacks data, limiting the application of simulation and flood forecasting. To address this, integration with geographical parameters specific to small- and medium-sized basins is necessary to enhance regional reliability and forecasting accuracy. Additionally, when applying deep learning to simulate basins with limited or no data, the significance of parameter synthesis becomes even more pronounced. Finally, we discuss the problems and challenges associated with storm flood calculations and parameter synthesis methods in small- and medium-sized basins and offer predictions regarding future research and technical developments. We recommend strengthening the use of emerging technologies for watershed runoff and runoff parameter calculations and advocate for their application in storm flood design.

The crime of human trafficking is an abnormal (involuntary, passive) phenomenon of population migration (disappearance, persecution); it has attracted great attention from the public and academic community because of its resultant social harm and far-reaching impacts on individuals and families. Constrained by the concealment, dispersion, variability, and complexity of the crime of human trafficking in China, the perspectives of earlier research topics were relatively clustered and limited. During the last 10 years, geographers have gradually achieved certain new understandings and progress through continuous exploration. From the perspective of the related sub-disciplines of geography, this study focuses on the main progress, existing issues, future trends, and crime governance paths to review studies on the crime of human trafficking in China. The results indicate the following: (1) Regarding the interdisciplinary situation: The crime of human trafficking is a social pain point of common concern among multiple disciplines. Geography has the advantage of being a latecomer and its integration with other disciplines will help understand the problem in depth and solve it systematically. Geographers will have a broad stage for future research in the field of human trafficking crimes. (2) Regarding the research objects: The earlier studies on the crime of child trafficking in China in the international context were actually subject studies of human trafficking in the Chinese criminal law context. The crime of human trafficking in China is unique compared to other countries and other types of crimes. (3) Regarding the research data: In the past, the data sources mainly comprised non-governmental organizations and individuals. The current data sources show the co-occurrence of non-governmental and official sources and the trend of the integration of offline and online availability. The integration and utilization of multi-source data will be the main path to future studies. (4) Regarding field investigation: In the context of the COVID-19 pandemic's impact and the upgrading of related family tracing means, field investigation has opened up new ways, and online investigations (online interviews, participatory observation in live broadcasting rooms, etc.) have become complementary or alternative channels of traditional field investigations and surveys. (5) Regarding patterns and trends: Based on the update and verification of available data, it is found that the stability of the spatiotemporal pattern of trafficking crimes and the dependence on the main routes in China, and cross-border and inter-provincial border areas, are worthy of attention. Future research trend will shift from being independent to comprehensive—from a quantitative study to a qualitative or mixed study; from case numbers to individuals, families, and their social networks; from the source area to the bridging of source, flow, and sink areas; and from a type of human trafficking to multi-type comparisons of missing persons. (6) Regarding measures and suggestions: Combined with the existing research knowledge and current crime trends, this study presents overall strategies and specific paths for dealing with the crime of human trafficking and assisting the abducted and their relatives.

The digital economy, an essential engine for the high-quality development of China's economy, has the potential to become a breakthrough in promoting the rapid recovery of tourism. From a spatial perspective, this study used panel data from 284 prefecture-level and higher cities in China from 2011 to 2019 and constructed a spatial Durbin model (SDM) to empirically test the spatial effect and mechanism of the digital economy on tourism development. (1) Digital economy and tourism development showed significant positive global spatial autocorrelation during the study period. Hotspots of the digital economy have long been located in southeastern coastal areas, and cold spots in central and western China have shrunk significantly. Tourism development hotspots are mainly distributed in the Yangtze River Delta urban agglomerations and in Yunnan, Guangxi, Guizhou, and Chongqing. Cold spots were distributed in the central and western cities of the Shandong Peninsula and gradually expanded southward. (2) In China, the digital economy has a significant direct effect and positive spatial spillover effect, which was confirmed by a series of robustness tests were conducted. From the perspective of different regions, although the direct effect was significantly positive in all regions, the influence coefficient in the eastern region was significantly larger than that in the central, western, and northeastern regions. The spatial spillover effect is entirely significant in the eastern region, partly significant in the central and northeastern regions, and not significant in the western region, indicating that "digital segregation" exists in the western region. (3) The positive spatial spillover effect of the digital economy on tourism development is optimal at 300 km. Subsequently, the spatial spillover effect followed the law of geographical distance attenuation. The spatial spillover effect reaches the critical point of the practical effect at 800 km and almost disappears at 1500 km. (4) Among the digital economy components, digital infrastructure, digital industry development, and digital inclusive finance can significantly promote local tourism development. However, only digitally inclusive finance has a significant positive spatial spillover effect, and the effects of the remaining components are insignificant. This study constructs an analytical framework for the spatial effects of the digital economy on tourism development and conducts rigorous empirical research to compensate for the limitations of current research from a local perspective. This study also examined the spatial effects of various components of the digital economy, which helped identify the source of the impact of the digital economy on tourism development more accurately. In addition, the regional heterogeneity and distance attenuation law of the spatial effect of the digital economy on tourism development were analyzed, and customized policy implications were proposed based on the research conclusions. Overall, this study has essential reference value for achieving high-quality tourism development and expanding the scope of digital economy application.

As an important land and water transition zone on Earth, wetlands are good places for birds to breed and roost. Bird monitoring has become an important index for assessing the biodiversity and ecological environment of a region. Nansha Wetland Park in Guangzhou is rich in biological resources and provides an important resting and wintering ground for global migratory birds as it is located on their migration route from East Asia to Australasia. To understand the migration patterns and annual dynamic changes of birds in the Nansha Wetland Park, line- and point-transect surveys were conducted to collect bird species and abundance data from January 2014 to December 2018. First, our results showed that 139 birds were recorded during the study period, of which migrant species were dominant. Combined with the available literature, a total of 186 bird species were recorded, belonging to 17 orders and 49 families. Of these bird species, 165 are under various levels of protection. Second, while the interannual changes in bird abundance were substantial, those of bird species richness were not, indicating that bird species tended to reach maximum abundance in bird communities. When compared to bird abundance in 2015, the number of individuals was relatively stable in other years of investigation, and the number of investigated species was the highest in 2017. Finally, monthly changes in bird species were in accordance with the annual rhythms of migration. Specifically, bird species richness increased rapidly during the wintering period, but remained constant during the breeding period. In addition, the migration time of waterbirds tended to increase over time. This may be related to a warming climate that prompts birds to migrate earlier. Differences in habitat patches are important influencers of bird feeding habits, and thus bird distribution and habitat. Among the habitat patches investigated, birds were primarily distributed in shallow tidal flats with rich food sources and in tall and lush mangrove communities, such as those containing the species Sonneratia apetala. Notably, the number of Platalea minor, a key indicator bird species, has increased steadily, with an increase of 346.15% from 26 in 2014 to 116 in 2018. The annual and monthly dynamic changes of birds in different areas showed subtle changes in individual numbers but generally showed a stable trend, which may be related to the environmental capacity of the habitat. The number of species and individuals that can be sustained by the environment tended to be saturated; that is, the maximum number of species that can be accommodated by the Nansha Wetland Park. Taken together, these findings suggest that bird species diversity could be promoted by expanding the area of tidal flats, increasing the planting area of mangroves, reasonably reclaiming wetlands, and maintaining the proportion of shallow water tidal flats and mangroves.

Tropical forests are considered the most abundant source of biodiversity in the terrestrial ecosystem and the key to international biodiversity conservation. Due to the rapid process of urbanization and land conflicts, regional ecological security is under tremendous pressure, resulting in biological habitat destruction, ecosystem service degradation, biodiversity reduction, etc. Consequently, the construction and optimization of ecological security patterns can improve ecological environment stability, restore ecological function, and protect biodiversity, which is an important spatial way to solve regional ecological environment problems and improve regional ecological security. In this study of Xishuangbanna, Yunnan Province of China, ecological sources were obtained through ecological system service and ecological sensitivity comprehensive superposition, followed by ecological source extraction through hot spot analysis. The resistance coefficient was modified on the basis of the land cover type through landscape fragmentation comprehensive index construction, and Linkage Mapper calculation was performed to calculate ecological corridors and nodes with the ArcGIS cost-distance analysis module to construct and optimize the ecological security pattern in the Xishuangbanna area. The main results are as follows: (1) Twenty important ecological source areas were extracted from the Xishuangbanna area, covering a total of 7,709.56 km² and accounting for 40.33% of the study area. The coincidence rate with the existing nature reserves is 89.92%, which is mainly distributed in natural reserve areas, such as the northern part of Jinghong City, Central and southern parts of Mengla County, and the southern part of Menghai County. (2) Compared with the resistance surface corrected by night light data, the spatial differentiation of the landscape resistance surface corrected on the basis of landscape fragmentation is more significant. Among this, the identification of ecological corridors, the spatial distribution of the corridors, the reduction of conflict points of human activities, network connections, and optimal corridor verification delivered relatively better results. (3) The ecological corridor, which includes the key corridor and the potential corridor of 278.59 km and 631.73 km, respectively, shows a spatial pattern combined with the half ring and the small rings. Moreover, the ecological nodes include 20 resource strategic points, four ecological strategic points, 27 ecological temporary rest points, and 24 ecological fracture points. (4) By referring to the ecological security patterns of Xishuangbanna area, the layout of the ecological spatial structure was optimized as "one belt, one corridor, and four groups." "One belt" was the ecological river corridor belt with the Lancang River as the main axis and the tributaries on both sides. "One corridor" refers to the central corridor structure connecting the national nature reserves of Mengyang, Naban River, and the Mangao Nature Reserve. Based on the existing nature reserves, the four groups were divided into the Bulong-Mangao nature reserves, Menglun three sub-reserves, Mengla-Yiwu-Mengyang-Menglun nature reserves, and Mengla-Shangyong nature reserves. This study provides a practical case for formulating ecological and environmental protection in Xishuangbanna.

With regard to China's vigorous promotion of environmental governance and ecological restoration, farmers around mines are victims of environmental damage and major participants in ecological restoration. Their willingness to participate is related to whether the government's environmentalpolicies can play a good role. This study developed a structural equation model of the impact of environmental perception on pro-environmental behavior willingness and conducted an empirical study using survey data of farmers around the Dabaoshan tailings area in Shaoguan in 2020. Value perception includes "economic value" and "ecology value", which was measured by the two observable variables "increasing income" and "improving the surrounding environmental quality". The results showed that value perception had a positive impact on farmers' willingness to be environmentally friendly, and that the standardization coefficient of the "increase in income" variable was higher, which meant that if farmers felt that environmental governance in the tailings area could bring them economic benefits or improve the ecological environment, they were more inclined to participate in environmental governance activities in tailings areas, and local farmers paid more attention to economic interests. Endowment perception represented farmers' self-efficacy, which was measured by "energy perception" and "ability perception". The above two variables strongly influenced farmers' willingness to be pro-environmental. The results showed that the higher the self-efficacy evaluation of farmers, the stronger their willingness to participate in environmental governance of the tailings area. Policy perceptions including exemplary norms and command-line norms were measured by "government attitudes", "attitudes of miner" and "attitudes of neighbor and friend". The results showed that policy perception had a direct impact on farmers' willingness to pro-environmental behavior, but this was due to an indirect impact by affecting farmers' value perception and policy perception, and "mining enterprise attitude" was the policy perception where the important variables were explained. Therefore, improving farmers' value perception and endowment perception through policy perception could also indirectly improve their willingness to exhibit pro-environmental behavior. Based on the above results, this study puts forward relevant policy implications. First, traditional media, newspapers, and TV should combine with emerging online platforms such as Douyin and Kuaishou to expand publicity channels. As rational economic people, farmers naturally attach great importance to the value brought about by participating in environmental governance in tailing areas. Therefore, it is necessary to publicize the economic and ecological value of environmental governance in the tailings area in a simple and easy-to-understand way and to make the publicity more targeted. Second, it is necessary to strengthen employment guidance and vocational education, improve the technical literacy of local farmers, lower the threshold and cost for farmers to participate in environmental governance, and encourage them to make scientific decisions. Last but not the least, it is necessary to build an ecological restoration exchange platform, strengthen the demonstrative role of neighborhoods, break the information barriers between the government and farmers, and explore effective leading models.

Linguistic landscapes, which refer to language and text displayed in public areas with a certain scale or visual impact, have become samples for geographers to conduct multi-type regional research and to examine social and cultural phenomena. In tourist destinations, such landscapes are often found in the form of signs, slogans, and billboards throughout public spaces, helping visitors quickly access information and understand the locale. Inn names are representative linguistic landscapes in rural tourist destinations, embodying operators' profound understanding of place and tourism relationships, reflecting tourists' emotional cognition of the destination. Analyzing their evolution helps to deeply understand the local development process and provides a decision-making reference for future development. This study selects Shuanglang Ancient Town in Dali, Yunnan Province as a case study. Semi-structured interviews, textual analysis, and GIS spatial analysis are adopted to interpret the complex relationship between inn names and local transformation development, attempting to answer how the inn names present spatiotemporal evolution characteristics and adapt to the transformation development of rural tourism destinations. Field investigation revealed that "resident guests" and local Bai ethnic villagers are the producers of the inn's linguistic landscape, following a bottom-up development model, but later indirectly influenced by the government. In the temporal dimension, the inn's linguistic landscape has undergone a development process from gradual enrichment to decline and then to stabilization, with landscape elements dominating. In the spatial dimension, it presents an unbalanced spatial structure, with areas such as Haixia Street, Tianshengying, and Laoyugang featuring significant coastal characteristics and having the highest concentration of the inn's linguistic landscape. The linguistic landscape of Shuanglang inns presents typical audience design characteristics influenced by the market as well as self-expression characteristics influenced by the inn operators' identities. Under the comprehensive influence of modernity and mobility, the spatiotemporal evolution of Shuanglang Ancient Town's inn linguistic landscape is closely embedded in the tourism destination construction and consumption process, with increasing tourist flow, tourists' romantic imagination of Shuanglang, and the self-reflection of migrant tourists driving the production of diverse categories in the linguistic landscape. Meanwhile, the unique natural landscape, limited living space, and pursuit of commercial interests drive the spatial evolution of the inn's linguistic landscape. The rural tourism destination image of "poetry and the distant" is continuously reinforced in the inn's linguistic landscape. In terms of innovation, this study provides new findings for existing research that considers the evolution of tourism destination linguistic landscapes as presenting "audience design" characteristics. Some "counter-market" linguistic landscape evolution characteristics are, in fact, modern people's escape from modernity. However, this behavior is not merely negative; the "warm writing" of the inn's linguistic landscape on living spaces can be regarded as an important practice for their aspirations toward a better life.

The provision of a high-quality ecological environment is essential for the quality of life of residents. As an important component of the urban ecological environment, the relationship between urban green spaces and public health requires further investigation. This paper provides a comprehensive review of the Chinese and international literature on how urban green spaces affect mental well-being. First, it introduces different approaches of measuring the use of and exposure to urban green spaces. The most commonly used indicators for measuring the use and exposure to urban green spaces include Surrounding Greenness, Access to Green Spaces, Green Viewing Rate and Green Space Quality and Usage Satisfaction. The main advantages of Surrounding Greenness are wide spatial coverage, long timespan, and low cost; however, the accuracy of measuring exposure is relatively low. Researchers have extensively used access to green spaces. Because the bird's-eye perspective cannot fully reflect resident perceptions of park green spaces, scholars have used the green view ratio, which has the advantages of wide coverage, low cost, easy access, and small data deviation. Greenspace quality and usage satisfaction are also important measurement indicators, and their main advantages are low operational difficulty and the ability to reflect residents' subjective evaluations more accurately. It then elucidates the "environmental stress reduction-restoration-instoration" mechanisms underlying the effect of urban green spaces on mental well-being. Specifically, urban green spaces can affect the mental health of residents by reducing the harm arising from heat and pollution, restoring capacity, and building capacity. Green spaces alleviate environmental pressure by purifying air, reducing noise, and alleviating the heat island effect, thereby promoting residents' mental well-being. People can alleviate their psychological stress and restore their ability to control attention by viewing green spaces, thereby protecting their mental health and providing a favorable and convenient venue for residents to conduct physical activities and socialize with their neighbors, which is beneficial to their mental wellbeing. Subsequently, it illustrates the moderating effect of opportunities to use urban green spaces, motivation to use urban green spaces, and ease of using urban green spaces on mental wellbeing from a "socio-ecological" perspective. Finally, it indicates that the current body of literature has several limitations and that future research agendas should be centered on research content, data, perspectives, and methods. Specifically, (1) for research content, the effect of green spaces on the mental well-being of different social and cultural groups is poorly understood. Therefore, it is necessary to strengthen the analysis of the sociocultural mechanism of the effect of urban green spaces to enrich the existing research framework. (2) Most previous studies used one method to measure the level of greenspace exposure or usage. It is advisable to use a variety of methods to measure the level of greenspace exposure or usage both subjectively and objectively. (3) From a research perspective, most previous studies have used a research paradigm based on local and static analysis, failing to solve the Uncertain Geographic Context Problem (UGCoP). Therefore, it is necessary to adopt a human-centered perspective and accurately measure the impact of green space exposure on residents' mental well-being in their residential neighborhoods, workplaces, and other activity spaces. (4) Researchers need to solve the problem of residential self-selection when investigating the effect of urban green spaces on mental well-being and explore nonlinear complex relationships using advanced methods such as machine learning.

Mangroves occur in coastal intertidal zones and play an important role in terrestrial and marine carbon cycles. Accurate estimations of mangrove carbon stocks and sequestration potential can help quantify the contribution of mangroves to addressing climate change and achieving carbon neutrality goals. The carbon stocks and burial rates of different mangrove communities and regions in Guangdong Province were studied through literature collection and data integration. The soil carbon densities of the Rhizophora stylosa and Bruguiera gymnorhiza communities were 0.27 and 0.23 Gg C/hm², respectively, while the soil carbon density of the Kandelia obovata community was the lowest at only 0.13 Gg C/hm². The area of mangroves in Guangdong Province is 9,106.2 hm², the total carbon stock is 1,542.02 Gg C, and the soil carbon density is 0.23 Gg C/hm². The total carbon reserves of mangroves in thirteen regions are in the following order: Zhanjiang (894.5 Gg C) > Yangjiang (195.4 Gg C) > Jiangmen (97.7 Gg C) > Zhuhai (91.0 Gg C) > Maoming (59.6 Gg C) > Shantou (51.4 Gg C) > Zhongshan (49.2 Gg C) > Huizhou (36.1 Gg C) > Guangzhou (35.1 Gg C) > Shenzhen (18.3 Gg C) > Shanwei (10.8 Gg C) > Dongguan (2.83 Gg C) > Chaozhou (0.11 Gg C). Using the ²¹⁰Pb method, the sediment accretion rate was found to be 13.47 mm/a. Qi'ao Island had the highest sediment compaction rate of 31.5 mm/a, followed by Zhenhai Bay, with 16.5 mm/a, Shenzhen Futian, with 15.9 mm/a, and Leizhou Bay, with the lowest sediment compaction rate of 7.3 mm/a. The carbon sequestration capacity of Guangdong province is approximately 19.72 Gg C/a, with the Leizhou Peninsula having the highest (6.05 Gg C/a) and Futian, Shenzhen having the lowest (0.66 Gg C/a) capacities. The carbon storage of mangroves in Guangdong Province was 1,542.02 Gg C, which was higher than that in other regions. The carbon sequestration capacity of the mangroves was relatively strong. Therefore, the protection and restoration of local mangroves may substantially contribute to the mitigation of climate change while providing additional benefits. This assessment, on a provincial scale, provides insights into blue carbon sequestration capacity, thus contributing to the synchronous progression of blue carbon management.

The issue of "spatial justice" has become a hot topic among urban research and planning scholars in China. An analysis of 1516 English-language documents in the Web of Science (WOS) from 2000-2021 was conducted through CiteSpace. Knowledge maps of keyword clustering, core author groups, and research institutions were mapped to reveal the hotspots and trends of foreign spatial justice research. The results reveal the following: (1) Foreign literature issuance exhibits a phased upward trend, divided into three stages of exploration (S1), stabilization (S2), and explosion (S3). The publication volume increased steadily in S1, contending and flourishing around the theme of space deprivation, exclusion and poverty. The publication volume has increased significantly in S2 compared with S1, the connotation of spatial justice is gradually clear and complete, environmental justice has received significant attention, and the influence of process and procedural justice is increasing. The spatial justice research has explosively grown in S3, focusing on the value effect and practical significance of spatial justice in the post-globalization era and stock development period. (2) A total of three hotspots emerged in foreign spatial justice research: The rise of research targeting youth and children, who have become one of the main actors and are motivated by awareness and environmental change to actively participate in the fight for justice on a global scale. Environmental justice research is booming with divergent and extended content, focusing on waste trade and climate change. The public and green spaces of the city have become research hotspots as the pursuit of spatial justice value turns to high quality and sustainability. (3) Trends in spatial justice research abroad include integration of environmental justice and urban space, as well as scale synthesis and thematic expansion driven by technological progress. In general, the maturation of foreign spatial justice research provides an important reference for the theoretical construction and practical application of spatial justice in China. How to connect with the international frontier, form research results with local characteristics, and effectively implement them in current spatial practice in the context of new urbanization is an urgent issue to be solved.

Guangdong Province is actively building a national marine ecological civilization construction demonstration area, and it is crucial to conduct research and assessment on the resources and environmental carrying capacity of the coastal zones. Under the guidance of the "double evaluation" of the territorial space planning, this study takes the coastal areas of Guangdong Province, namely the 45 coastal counties and the sea areas within the scope of the marine functional areas of Guangdong Province as the research scope It proceeded from the functional orientation of ecological protection, agricultural production, and urban construction to construct the evaluation index system of the resources and environmental carrying capacity of the coastal zone of Guangdong Province. In 2019, based on the evaluation index system, a comprehensive evaluation of the resources and environmental carrying capacity of the coastal zone of Guangdong Province was performed using integrate and integrate multi-scale spatial data, remote sensing, geographic information system, and other technical means and its resource and environmental carrying status were quantitatively revealed. The results showed that approximately 84% of the land area in the coastal zone and more than 1/2 of the sea areas (cities, districts) have overall good comprehensive bearing status of the resources and environmental carrying capacity, which is mainly characterized by loadability. The scale of human socio-economic activities in most regions is within the range of the resources and environmental carrying capacity; however, in some regions it exceeds the threshold, particularly in regions distributed in the Pearl River Delta. Specifically, under the guidance of the ecological protection function, 60.05% of the land area and 14 counties (cities, districts) of the sea area are in a loadable state, mainly distributed in the east and west wings of the urban agglomeration in the Greater Bay Area of Guangdong, Hong Kong, and Macao. Under the guidance of the agricultural production function, the carrying capacity of land agriculture is relatively severe, mainly critical overload, while the number of counties (cities, districts) that can be carried by sea agricultural production is relatively small. Compared with the functions of ecological protection and agricultural production, the area of the loadable area under the urban construction function is the highest, with 86.93% of the land area and 29 counties (cities, districts) of the sea area in the loadable state, and only 3.01% of the land area and 10 counties (cities, districts) of the sea area in the overloaded state. Guangdong Province is a major province of marine economy. As an important place for economic activities in the coastal zone, the ocean is a strategic place to promote the high-quality development of Guangdong Province.. Under the mode of sustainable development, there is still a large scope for the development of resources and environmental carrying capacity in the coastal zone of Guangdong Province. On the premise of ensuring the stability of resources and environment, the loadable area can be further developed and utilized selectively, the allocation of resource elements can be optimized, and a new management mode of high-level protection and efficient utilization of resources can be built. Thus the research results provide a basis for the compilation of territorial space planning and the optimization of territorial space development and protection pattern in Guangdong Province.

The Wuyi Mountains preserve the most complete central subtropical forest ecosystem in the subtropical zone, where the vegetation and soil have a distinct vertical distribution with elevation. To investigate the relationships between surface pollen assemblages and vegetation in this area, 76 samples of modern surface pollen with minimal human interference were collected from various elevations in the Wuyi Mountains. Based on the results of cluster analysis and redundancy analysis (RDA), this study indicates the connections between the distribution of pollen taxa at different elevations and under different climatic factors. The primary findings are outlined as follows: 1) Pinus, Castanopsis/Lithocarpus, Cyclobalanopsi, Quercus (evergreen), Taxodiaceae, Schima, Rutaceae, Ilex, Rosaceae, Poaceae, and Artemisia were the dominant pollen taxa, generally corresponding to the modern subtropical broadleaved evergreen forest. The pollen assemblages showed clear changes with variation in altitude; the relationships between pollen taxa and elevation were divided into three patterns: The low altitude areas (0-450 m) had a high percentage of Castanopsis/Lithocarpus, Quercus (evergreen), Theaceae, Schima, Ilex, Poaceae, and Dicranopranis. In the middle elevation area (450-1,850 m), Castanopsis/Lithocarpus, Pinus, Taxodiaceae, Tsuga, and Quercus (evergreen) were common. The higher altitude area, at approximately 1,850-2,200 m, was characterized by the dominance of Pinus, Poaceae, and Dicranopteris. 2) The results of RDA and cluster analysis divided surface pollen samples into different communities. RDA results also showed that the mean annual temperature, mean annual relative humidity, mean annual precipitation, mean precipitation of the coldest season, and mean precipitation of the warmest season were the main climatic factors that controlled the distribution of modern pollen. 3) The results of the representative analysis of pollen showed that Castanopsis/Lithocarpus, Pinus, Quercus (evergreen), and Artemisia were over-represented, and the genera Tsuga and Poaceae were represented less; 4) lower elevations had a significant presence of Poaceae, Artemisia, and Pinus. The pollen content of Quercus (evergreen) was low and the pollen type was relatively simple; it was related to the development of artificial pinewood in the foothills and the high spore content in the secondary forest, which indicated heavy human activity in the low altitude area. Therefore, these results revealed that the surface pollen assemblage varied significantly through the vertical vegetation zones in Wuyi Mountains of south subtropical China. The characteristics of surface pollen distribution were mainly affected by vegetation composition, habitat, and human activities, which is a crucial reference for reconstructing the paleovegetation and paleoenvironment in this region and similar areas.

The Shanwei Special Cooperation Zone (SSCZ) in Shenzhen is the main distribution area of the Lianhuashan Fault Zone. Two large ductile shear zones pass through the SSCZ. The ductile shear zone of the SSCZ is henceforth referred to as "the zone". Severe plastic progressive deformation, stretching, and compression occurred in the late Jurassic-Neogene period in the zone, because of which the structure and properties of the rock mass underwent significant changes. There are three levels of structural planes in the zone: brittle faults, schistosity planes, and joints in the rock mass. The ductile shearing action changes the rock mass structure, leading to poor integrity. According to existing data, the compressive strength of the rock in the zone is equivalent to 0.31-0.86 of the original rock, indicating that the strength of the rock is obviously attenuated by ductile shear action. Using ground investigation and remote sensing, we found 1,614 topsoil slips in the zone. The density of topsoil slips in the hillside area (16.2 topsoil slips per km²) was much higher than that outside the zone (1.3 topsoil slips per km²), indicating that the slopes in the zone are more prone to shallow damage. To study the geological risk zonation of geological hazards in the SSCZ, it is necessary to determine the characteristics and distribution rules of topsoil slips in the zone, analyze its causal mechanism, and predict its development trend.ⅰ) Ground surveys and remote sensing showed that monocase topsoil slip is small in the zone and sliding mainly occurs along the bedrock surface. Sliding masses are mainly solid and completely weathered rock. ⅱ) The frequency of geological disasters under the action of certain factors in the study area is divided by the frequency of geological disasters in the area. The natural logarithm of the divisor is taken as the information value to evaluate the relationship between geological disasters and various factors. The results show that the density of topsoil slips is positively correlated with the degree of ductile deformation (strong→medium→weak), distance from brittle fracture (near→far), and topographic slope (high→low). Moreover, the distribution density is strongly related to the geomorphic unit, slope direction, original rock type, and slope type. ⅲ) The above analyses are combined with regional, geological, exploration, meteorological, and other data. Results from this combination show that topsoil slips in the zone are produced under weak background conditions formed by the influence of multi-stage tectonic action dominated by ductile shear forces, the slow rise of the hillside area, and the induction of typhoons and rainstorms. Their development and changes are characterized by migration, self-healing, and expansion. ⅳ) Most of the current topsoil slips occurred during Super Typhoon Mujigae in 2015, after which the region experienced several rainfall events with intensities higher than those of Typhoon Mujigae, yet the number of topsoil slips did not increase significantly. This shows that after a general shallow sliding event, the sensitivity of the slope to shallow damage decreased, and generation took a long time before entering the next outbreak period.

Territorial space ecological restoration has become a significant strategy for the construction of China's ecological civilization. It is also an important strategic task related to national ecological security and human well-being. The continuous expansion of space in urban agglomerations and the high-intensity development of cities have exacerbated the fragmentation of natural landscapes. The ecological security of urban agglomerations and the ecological restoration of territorial spaces have become key issues of common concern to the government and scholars. Currently, the research on ecological restoration of territorial space mostly focuses on the identification of ecological restoration areas based on the key components of ecological security patterns and rarely discusses the coordinated protection and restoration of urban agglomerations by combining the ecological security patterns with human activities. It is particularly necessary to identify the ecological restoration areas and build a technical paradigm for ecological protection and territorial space restoration that can provide a basic support for the ecological integration, construction, and sustainable development of urban agglomerations. Based on ecological network construction and human disturbance assessment, this study diagnoses the territorial space ecological restoration areas of Guangdong-Hong Kong-Macao Greater Bay Area and proposes ecological protection and restoration strategies for the territorial space ecological source restoration area, ecological corridor restoration area, and stepping stone restoration area. The results showed that: (1) Human activities in the Guangdong-Hong Kong-Macao Greater Bay Area had high interference intensities and a wide impact on the ecological environment; areas with high and relatively high interference accounted for 48.65% of the total area, mainly concentrated in the central part of the Greater Bay Area. (2) The ecological network of Guangdong-Hong Kong-Macao Greater Bay Area presented a relatively stable characteristic pattern of "2 breadth lines and 4 length lines". The 2-breadth lines included the continuous mountains in the north and the ecological protection belt of the southern coastal waters. The 4-length lines included the eastern and western land corridors and the central water corridors. (3) The ecological source restoration area of the Guangdong-Hong Kong-Macao Greater Bay Area was 4,687.42 km², the ecological corridor restoration length was 1,362.71 km, and the stepping stone restoration area was 833.82 km², mainly distributed in Zhaoqing, Huizhou, and Jiangmen. To limit human disturbance and restore ecological functions, strategies for territorial space ecological restoration were proposed based on the ecological network function and structural integrity; (4) It is urgent for government departments to overcome the concept of regionalism and build a consensus on the co-disposal of ecological restoration in the territorial space. The construction of cross-domain collaborative governance institutions will efficiently promote the ecological restoration of cross-regional territorial spaces. Considering both human and ecological systems, this study discussed the ecological restoration schema in key areas of ecological networks, coastal ecological restoration areas, and trans-regional ecological restoration areas. The method for urban agglomeration territorial space ecological restoration was formed, including "ecological network pattern-human activity disturbance-restoration area diagnosis-restoration strategy," which will provide a framework for promoting the territorial space ecological protection and restoration in the Guangdong-Hong Kong-Macao Greater Bay Area.

Combined with flood risk avoidance-oriented urban expansion strategies, future urban expansion spatial patterns were simulated under Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs) scenarios. This study compared urban expansion and expected annual damage to evaluate the flood mitigation effects of different strategies. The results show many newly expanded urban lands in the Pearl River Delta are located in floodplains, and the expected annual damage caused by floods is enormous. The most serious economic losses caused by floods were concentrated in southern Guangzhou, eastern Foshan, northern Zhongshan, and northwestern Dongguan. Under the SSP5-RCP8.5-natural expansion scenario, the newly expanded urban lands in floodplains of the Pearl River Delta in 2080 will be 1,633 square kilometers (equivalent to the built-up areas of Guangzhou, Foshan, and Zhongshan combined in 2021), accounting for 31.5% of the total newly expanded urban lands; the expected annual damage will be 2,341.3 billion yuan. If humans manage to reduce emissions in the SSP2-RCP4.5-natural expansion scenario, newly expanded urban lands located in floodplains can decrease to 1,059 square kilometers (-35.1%), accounting for 29.8 % of the total newly expanded urban lands, and the expected annual damage can be reduced to 1,416.5 billion yuan (-39.5%). If flood risk avoidance strategies are included in the urban expansion to optimize and control the spatial pattern of urban expansion, the direction of future urban expansion can change and steer away from areas with high flood risk and toward areas with low or no flood risk. Under the SSP5-RCP8.5-flood risk avoidance scenario, newly expanded urban lands located in floodplains can decrease to 1,358 square kilometers (-16.8%), accounting for 26.2 % of the total newly expanded urban lands, and the expected annual damage can be reduced to 2,001.0 billion yuan (-14.5%). According to the assessment results, emission reduction, and flood risk avoidance strategies can effectively reduce future flood risks. This study improves our understanding of flood risks under different future scenarios, provides a practical reference for developing flood mitigation and urban planning policies in the Pearl River Delta, and motivates decision-makers to formulate corresponding strategies early and e?ectively to mitigate future flood risks.

The novel coronavirus disease 2019 (COVID-19), which spread all over the world at the beginning of 2020, exerted significant impacts on the substantial economic and social development in China, seriously affecting the production and operation of Chinese small and medium-sized enterprises (SMEs). As the COVID-19 pandemic was effectively controlled by the central government, China's economy manifested strong economic resilience during the process of recovery. Under these circumstances, it provided a valuable opportunity to examine the dynamic evolution and mechanism of economic resilience over a relatively short period. In economic geography research, structure and agency are the two main influencing factors for regional economic resilience; specifically, structural factors refer to the economic diversity and inherited structure of a regional economy in building resilience capacities, while agency factors focus on the role of agentsin a resilient economic system. However, the existing literature has focused heavily on structural factors, but the effect of agency factors has gained less attention. Based on interviews with 43 manufacturing SMEs in Dongguan in 2020, this study 1) investigates the dynamic evolution and characteristics of short-term economic resilience from an agency perspective and 2) demonstrates the micro-mechanism of reconstructing economic resilience at the enterprise level by constructing a structure-agency framework. The study derives several findings. First, economic resilience is not an inherent attribute of an economic agent. In the short term, the formation of economic resilience can be divided into a three stage process from cognition to adaptation, and then to reconstruction. Each stage manifests different agency characteristics. Second, the reconstruction of economic resilience is strongly influenced by the individual (entrepreneurs) and collective agency (supplies and customers) in the COVID-19 shock. For individual agencies, manufacturing SMEs are sensitive to perceiving and seizing the "opportunity space," which is technologically related to their primary products. For collective agency, many entrepreneurs actively offer financial support to their upper and lower reach enterprises to enhance economic resilience by forming collective networks. Third, structural factors (i.e., industrial structure, institutional arrangement, and infrastructure construction) also influence the formation of economic resilience in a short period. In the case of Dongguan, industrial structure and institutional arrangements contributed to enterprises' return to normal production during the COVID-19 crisis, while the imbalance of infrastructure structures (including basic social and public services) plays a constrained role in economic resilience. Moreover, three theoretical implications are proposed: emphasizing the transformation between short-term adaptation and long-term adaptability, concerning the shaping of structural factors caused by agency, and paying attention to the coupling between agents and external connections.

Human activities such as deforestation, farming, and uncontrolled construction have had a negative impact on mangrove areas in the Reserve. This paper explores how the mangrove area and space have changed since the establishment of the Dongzhaigang Mangrove Nature Reserve, as well as the relationship between this change and the community residents around the Reserve. Six remote sensing images, from 1976 to 2021, were used to obtain wetland data of different ages in the Dongzhaigang Mangrove Forest Nature Reserve in Haikou City. Using the transfer matrix, a questionnaire survey, and principal component analysis, we analyzed the changes in mangrove forests in protected areas and their relationship with surrounding communities over the past 45 years. The results show that: (1) From 1976 to 2021, the area of mangroves in the reserve has increased from 1,395.84 hm² in 1976 to 1,589.28 hm² in 2021, showing a trend of "suddenly slowing and rising" during this period, and the proportion of mangrove area has increased from 28.6% in 1976 to 32.6% in 2021, becoming the main wetland type. The largest decline (250 hm²) in the mangrove area was from 1976 to 1985. The largest growth occurred from 2005 to 2018, when the mangrove area increased by 190.08 hm². (2) From 1976 to 2021, 91.77 hm² of mangrove wetlands in the study area were converted into other wetlands, 10.71 hm² were converted into non-wetlands, and 267.71 hm² of other wetlands and 28.21 hm² of non-wetlands were converted into mangrove wetlands. In the same period, the transfer targets of mangrove forests in the reserve were muddy beaches (34.32 hm²), rivers (25.81 hm²), marine aquaculture farms (21.06 hm²), other land (10.58 hm²) and flooded wetlands/interiors. Land flats (8.26 hm²); silt beaches (177.41 hm²), rivers (38.18 hm²), other land (28.21 hm²), deltas/sands/sand islands (22.15 hm²), flooding Wetlands/inland tidal flats (21.79 hm²), and paddy fields (6.34 hm²) are the most common areas transferred into mangroves. (3) Fishing income from surrounding community-dwelling individuals was significantly associated with farming, disfiguring forest-digging pond areas, conservation awareness, and mangrove area variation. The factor quality of fishing practices (cos2), values of fishing practices and income, months of fishing, fishing volume, and conservation attitude in the surrounding community residents accounted for more than 0.6 in the principal component analysis of area change of mangrove forests, where the factor quality of fishing practices and fishing income were more than 0.8. The decline in residential fishing frequency corresponds with the shift in household income sources, the occupational move from fishing to wage and service industries, the obvious increase in conservation awareness and the conservation attitude of residents, and the transformation of the mangrove area away from serious destruction to less fragmentation. The contributions of freshwater farms, resident population, number of secondary schools, and village to mangrove distance factors were all greater than 10 and negatively correlated with mangrove area change. Therefore, it is necessary to explore the relationship between mangroves and community residents to obtain a scientific reference for the utilization, protection, restoration, and management of mangroves in the Dongzhaigang Mangrove Nature Reserve.

This study responds to the current rapid increase in research on the current focus and future direction of the impact of returned overseas talent on regional development at home and abroad, which still lacks a relatively systematic literature review. The study aims to provide a scientific basis for exploring the utility of talent returning from overseas. Using CiteSpace for the literature review, we retrieved 631 relevant papers in core journals from two databases, "Web of Science" and "China National Knowledge Infrastructure." With the help of quantitative statistics, collaborative networks, and keyword hotspot evolution, we analyzed and reviewed relevant studies and drew the following conclusions: First, based on the trend of increasing of literatures, the research shows a three-stage process from to 1998-2007, to 2008-2013, and 2014-present. The studies cover a wide range of topics, including regional innovation, economic development, and social differentiation, from multiple disciplines and perspectives, such as economics, management, sociology and geography. Second, the research is constantly expanding and deepening. The research subjects were refined from returned overseas talent as a whole to returnee entrepreneurs, executives, teachers, and other returned overseas talent in different fields. Research content has gradually shifted from technological progress and innovation to economic growth and enterprise efficiency and then to social structure and social cognition. The research results within each field were systematized. Lastly, The impact of returned overseas talent on regional development mainly stems from the advantages of human capital and international social capital contributed by the overseas experience of those returning. In the context of relatively underdeveloped regions, the impact of returnees on regional innovation, economic development, and social differentiation is widespread and multiscale, from the regional, organizational, and individual levels. To conclude, the research is based on regional realities; the theoretical contributions have gradually improved and diversified, and the research methods are both qualitative and quantitative. There is scope for future research on the following aspects: exploring the impact of returned overseas talent on regional development from a spatial perspective, looking at different spatial carriers in the region, the interaction mechanism between returned overseas talent and regional development, and the data sources, and methods used to study the impact of returned overseas talent on regional development.

Leisure tourism has become a new hotspot of tourism consumption and promotes the upgrading of tourism industry structure. Moreover, the examination of the spatial accessibility of leisure tourism resources is conducive to improving the tourism flow system. This study takes 3,612 leisure tourism resource points in Guangzhou as the research object. These resource points are classified into natural leisure, recreational leisure, cultural leisure, and special leisure types according to their nature. The study uses the nearest neighbor index and kernel density to analyze the spatial characteristics of different types of leisure tourism resources in Guangzhou. Based on the 500 m×500 m raster division, it employs the raster analysis method to calculate the accessibility of different types of leisure tourism resources in Guangzhou and further investigates the formation mechanism of the accessibility spatial pattern. The conclusions are as follow: (1) The spatial distribution of leisure tourism resources in Guangzhou shows a general characteristic of "dense in the central city and sparse in the peripheral areas". (2) The spatial distribution characteristics of different types of leisure tourism resources varied significantly, with the highest degree of concentration in the cultural leisure type and the closest random distribution in the special leisure type. In terms of the clustering pattern, the natural and recreation leisure types are clustered in the main city and its surrounding areas, the cultural leisure type is a single cluster in the old town, and special leisure type is clustered in a polycentric manner. (3) The spatial pattern of the accessibility of leisure tourism resources in Guangzhou reveals clear traffic directionality, and the distribution pattern of high-accessibility areas is consistent with the direction of expressways, and forms a multi-well structure in space. High-accessibility areas are concentrated in the main urban and suburban areas, which are rich in leisure and tourism resources, and the spatial pattern of accessibility is characterized by a gradual decline along the traffic arteries with the central urban area as the core, reaching its lowest point in the northern part of Conghua District. (4) The high-accessibility centers for the natural leisure type are primarily distributed in the main urban area and the area with dense resources; the high-accessibility areas for the recreation leisure type are distributed in a row and its overall accessibility level is high; the high-accessibility areas for the cultural leisure type essentially cover the three old districts and the southern portion of Tianhe District, with a low accessibility level in Conghua District. The special leisure type shows an obvious circular structure in the accessibility-related spatial pattern. (5) Based on the comprehensive effect of the "resource-transportation-population-administration" system, the accessibility pattern of leisure tourism resources in Guangzhou was gradually formed through the combined influence of the spatial concentration characteristics of leisure tourism resources, regional accessibility, leisure tourism market demand, and infrastructure construction.

Mangroves, which have extremely high primary productivity, are efficient coastal blue carbon ecosystems. Aboveground biomass (AGB) is an important component of vegetation carbon pools. Thus, accurate estimation of mangrove AGB is critical for studying carbon cycle and climate change. While the practical significance and application of information obtained on mangrove AGB in China is apparent, studies of this nature in China at a national scale have rarely been reported. Remote sensing technology is convenient, efficient, has a wide observational range, and can be used for large-scale ecosystem monitoring. Canopy height is a structural parameter that is positively correlated with the AGB of vegetation. The Global Ecosystem Dynamics Investigation (GEDI) spaceborne Light Detection and Ranging (LiDAR) satellite, launched in recent years, is able to obtain vegetation canopy height. This study employed forest canopy height derived from GEDI satellite-based LiDAR and an allometric equation based on the allometric theory to estimate mangrove AGB in China in 2019, and the quantitative and spatial distribution of mangrove biomass and their main influencing factors were analyzed. The results showed that the total and mean AGB of mangroves in China in 2019 were about 1,974,827 t and 73.0 t/hm², respectively. Guangdong-Hong Kong-Macao area showed the largest total mangrove AGB, reaching 843,836 t. The mean values of AGB in each province (region) with mangrove ecosystems nationwide ranged from 53.3 to 92.1 t/hm², of which the largest was found in Hainan Province, reaching 92.1 t/hm². In Hainan, Taiwan, and Fujian provinces, mean mangrove AGB was higher than the national mean. Considering nature reserves, the mean AGBs of mangroves in Neilingdingdao-Futian and Mai Po mangrove nature reserves in Shenzhen Bay in the Guangdong-Hong Kong-Macao area and Dongzhaigang mangrove nature reserve in Hainan province were relatively high, with values greater than 110 t/hm². The accumulation and distribution of mangrove AGB in China are affected by latitude and anthropogenic factors. This study provides a comprehensive analysis of mangrove AGB in China based on remote sensing and an allometric equation and can provide a database and technical reference for estimating carbon storage in mangrove ecosystems. It will also contribute to the implementation of ecological restoration and protection measures for coastal mangroves, as well as carbon emission control in China.

In recent years, the state has promulgated a series of policies aimed at establishing a national territorial spatial planning system and advocating for the creation of an integrated "multi-regulation in one" system. The issuance of these policies marked the formal commencement of constructing the territorial spatial planning system. Territorial space is a type of environment, and the description of its functions essentially elucidates the relationship between humans and land. This relationship represents a complex interplay of static and dynamic interactions among elements such as stakeholders, the environment, and activities within a defined spatiotemporal framework of the system. In the new era, territorial spatial planning is required to perceive, analyze, evaluate, and decide upon various resource elements and the spatiotemporal information of diverse activities of people within a national territory. Multi-source urban spatiotemporal data empowers the intelligent processes of perception, analysis, evaluation, and decision-making regarding these resources and activities, propelling the evolution from traditional to smart territorial spatial planning. This study aimed to construct a comprehensive framework for smart territorial spatial planning and multi-source urban spatiotemporal data application to promote the modernization of the territorial governance system and its capabilities. This was done by adhering to the fundamental principles of "ecological priority" and "human-centricity." Taking Guangzhou as an example, this study investigated how multi-source urban spatiotemporal data empowers the drafting, approval, and supervisory execution of smart territorial spatial planning. Multi-source urban spatiotemporal data support territorial spatial planning in four dimensions: sustainable development, high-quality growth, high-quality living, and high-level governance. For sustainable development, spatiotemporal data obtained from land surveys, ground/subterranean observations, and spatial planning outcomes, bolster the assessment of land resource carrying capacity and suitability evaluation for territorial development. This approach fosters optimized layouts for ecological, agricultural, and urban spaces and propel the construction of beautiful territorial spaces. Regarding high-quality growth, spatiotemporal data provide a robust foundation for data support and decision-making in national territorial space governance. In urban villages, multi-source data aid in enhancing the quality of high-density mixed-use spaces. In wholesale markets, data analyses assist in the optimal allocation of spatial resources, promoting orderly governance. In village-level industrial parks, spatiotemporal data underpin classified policymaking, refining industrial layouts. In terms of high-quality living, multi-source urban spatiotemporal data support the construction of diverse human-centric cities by precisely quantifying the level of street greening and estimating the demand for various public services. Regarding high-level governance, multi-source data facilitate the monitoring, assessment, and early warning of territorial space resources as well as the scientific adjustment and decision-making of related management measures. This data-driven planning approach provides scientific decision-making support for high-level urban governance, marking a transition toward more intelligent and refined territorial spatial planning. However, practicing smart territorial spatial planning in Guangzhou not only validates the empowering role of multi-source urban spatiotemporal data but also exposes the challenges in its application. The acquisition of multi-source urban spatiotemporal data is difficult and costly, and the absence of unified application guidelines presents challenges in data acquisition and comparison of analytical results. Consequently, the future research on smart territorial spatial planning should focus on establishing standardized data channels and application norms, enhancing the multi-source data integration and the construction of a "one map" platform, and fully incorporating interdisciplinary theories and technologies.

Recently, dockless bikeshare (DBS), a new bikeshare program that does not feature fixed dock stations, has been developed rapidly in China and has also offered a decent solution to the first- and last-mile problem. In addition, the integration of DBS and metro strongly promotes the transit-oriented development, particularly in the metropolitan areas of China. To achieve the seamless connection between DBS and metro transit, the spatial variation of the effects of urban built environment, particularly in high-density metropolitan areas, should be explored to advance the targeted policy interventions in different urban spaces. Using data from one of the largest DBS operators in China (ofo), this study measured the integrated use of DBS and the metro quantitatively, and it employed geographically and semiparametric geographically weighted regression (GWR and SGWR, respectively) to examine the effects of the built environment on the integrated use, using Shenzhen as a case study. The findings show that (1) The SGWR model performs better than GWR and OLS in explaining the relationship between built environment and access integrated use, whereas SGWR is not applicable for the egress integrated use. (2) Three positive determinants of population density, major road length and inbound metro ridership, and three negative determinants of metro density, secondary school, and intersection density have been examined with spatial effects on the access integration. (3) For egress integration, official land use, park, bus stops, and outbound metro ridership have positive and spatial effects, while residential land use, number of secondary school, metro density and distance to CBD (Central Business District) exert negative spatial effects. The results indicate that the built environment elements usually affect the integrated use with spatial variation. Furthermore, the access and egress integration use of DBS metro largely depends on the characteristics of built environment of the origin and destination metro catchment, respectively. This work provides insight into how the DBS-metro integration, which is divided into access and egress patterns, is spatially affected by urban built environment in the Chinese metropolitan context. The results will also provide a reference for the local government to carry out the targeted policies and planning to encourage the connection between DBS and metro transit more successfully. For DBS operators, the results also contribute to allocating the bikes more efficiently, which is adapted to the dynamic demand-supply at different urban spaces.

The dual-cycle new development pattern, a consequence of changing times, "superposes" multi-scale spatial-output theory and the regional division of labor under the condition of market economy. It also introduces a new force for developing new forms of urbanization. To explore this influence, the present study first internalizes two exogenous variables in urbanization-development dynamics: technological innovation and institutional reform. It then constructs a new urbanization-dynamics factors-analysis framework for the "four-dimensional driving forces model + innovation force + institution force", combines this with the principal component-regression model, which empirically analyzes the development dynamics of Chongqing's new urbanization since 2000. Accordingly, this study uses Porter's "diamond model" to systematically consider the new urbanization development path. The results demonstrate: (1) Innovation and institutional forces incorporated into the urbanization-dynamics factors-analysis framework have had a significant positive driving effect on the urbanization of Chongqing; of these, innovation is the most evident. The advantages of technological innovation and institutional reform now underpin development dynamics, responding to changing times in a new era; (2) Although the development of new urbanization in Chongqing is the result of "six-dimensional forces," market and administrative forces are still the primary driving forces, followed by innovation and internal and external forces. Here, the driving effect of innovation on urbanization has surpassed the impact of administrative force during the second stage of urbanization in 2010-2018. The least significant effect is institutional force; it indirectly reflects that Chongqing's urbanization is an endogenous process. It is forecast and objectively necessary to construct a new development pattern; (3) Based on Porter's Diamond Model, researchers have pointed out problems in Chongqing, such as small growth volume, limited hinterland, insufficient market-purchasing power, unsustainable development, low-end products, and serious homogenization. To address this, the present study introduces specific countermeasures and suggestions for realizing high-quality urbanization development, based on six dimensions: developing advanced production factors; creating a unified free-flow market of factors; expanding market demand; promoting urban development; cultivating and developing leading and supporting industries by "expanding domestic demand, adjusting structure and deepening opening to the outside world"; and, seizing the opportunity to "go out" and build a high-quality service-oriented government. These results are expected to provide a theoretical basis and reference for research on development dynamics of urbanization in China, the high-quality development of urbanization in Chongqing, and the integration of the Chengdu-Chongqing dual city economic circle.

The happiness of residents is an important component of the sustainable development of heritage sites. Most previous studies have focused on the happiness of tourists rather than that of residents. The development of tourism at heritage sites and the increase in the number of tourists may either improve residents' happiness by promoting local development or reduce their happiness because of the environmental pressure and large number of tourists. The question arises as to the kind of residents who are more likely to gain happiness from the development of tourism at heritage sites. Based on the theories of local knowledge and flourishing happiness, this study investigated the residents of Jianglang Mountain, a world natural heritage site, and examined a model of residents' local knowledge, subject-guest interaction, and happiness (i.e., work, life, psychological, and interpersonal happiness). The findings answer the research question: whether residents with local knowledge are better able to achieve happiness and how they do so. The results of the study show that at heritage sites, local knowledge has a direct impact on residents' work, life, psychological, and interpersonal happiness. The interaction between the host and guest played a mediating role in these four influence paths. Theoretically, this study emphasizes that interpersonal happiness is a critical component of residents' happiness, which enriches the understanding of happiness theory in the tourism field. Second, to the best of the authors' knowledge, this study is one of the first to link local knowledge with residents' happiness, as the concept of local knowledge is primarily applied in studies of tourism resource development. The findings indicate that residents with greater local knowledge can obtain the aforementioned four types of happiness more easily. The third theoretical contribution of this study is the role of subject-guest interactions. To improve the happiness of residents at heritage sites through the local knowledge approach, the interaction between the host and the guest is important as it gives residents more opportunities to pursue better work, life, psychological, and interpersonal satisfaction. From this perspective, tourism development is a necessary part of the sustainable development of heritage sites. If the protection of heritage is overemphasized and the rational use of heritage is not highlighted, it could be a double-edged sword. Tourist visitation and the development of the tourism industry activate and empower heritage sites, thereby ensuring the happiness of residents and the sustainable development of heritage. In practice, this study suggests enhancing residents' happiness through education regarding local knowledge and improvement of subject-guest interactions. Practical recommendations are provided at the end of this article.

Based on a literature review and policy analysis, this study investigates the evolution of China's railway investment and financing, planning, and development in the context of its market-oriented reform. The relationship between railway and multi-level spatial development is divided into specific periods. The features of different stages are summarized from the perspective of railway financing structure, route arrangement, station location, and their spatial effects. This study contributes to our understanding of the changing multi-level governance of railway development in China in the long run and the rationale of the pattern of high-speed rail network development in the country. With the establishment of China's market-oriented economy and its integration into economic globalization, the central and local governments have different interests and objectives in railway development, which have affected railway investment and financing structure, route arrangement, and station location, and finally resulted in different spatial effects of railway development. Since the establishment of the People's Republic of China, the relationship could be divided into four periods: i) railway services adapted to national economic and spatial development (1949-1978), ii) railway services lagged behind national economic and spatial development (1978-2004), iii) railway construction followed national economic and spatial development (2004-2013), and iv) railway construction led national economic and spatial development (2013-present). The main body of railway development, construction mode, and spatial effects were significantly varied across different periods. In the planned economy period, railway planning construction adapted to national strategic policies and social and economic needs. As China's institution of the market economy was established and urbanization and industrialization developed rapidly, railway construction was hindered by funding constraints, resulting in a significant gap between railway services supply and the increasing national transportation demand. Consequently, railway construction has gradually fallen behind national economic and spatial development. However, there are differences in the national and local interests between the central and local governments in planning and developing railway networks, which have driven the evolution of railway construction toward a multi-level construction mode. This mode centers around the national backbone network, dominated by the central government, and aims to promote the construction of national development corridors and urban agglomerations. The planning for metropolitan areas has been facilitated via inter-city rail networks, led by provincial and municipal governments. In this process, conventional railways are gradually being replaced by high-speed railways (HSR), which have become the priority of railway development. Subsequently, development has shifted from the construction of conventional railways to meet regional transportation and population flow needs toward the planning and construction of HSR that lead multiscale spatial restructuring. In the context of rapid expansion of high-speed rail development, some spatial problems emerged, such as negative impacts of HSR development on small and middle-sized cities, low land use efficiency in station areas, and weak functional connections between station areas and central cities. Therefore, to promote the coordinated development of urban agglomerations and metropolitan areas, it is necessary to develop station areas based on local and regional conditions and enhance the interaction of high-speed rail effects at different scales.

Street vendors are an indispensable part of the urban social ecosystem, but due to a lack of comprehensive understanding, many cities have adopted simple eviction policies, resulting in the gradual marginalization and stigmatization of the street economy. The efficient governance of street vendors requires the comprehensive investigation of their business scale and spatial distribution information. However, traditional methods have limitations in terms of automatically surveying large-scale street vendor information, particularly spatial distribution. This paper proposes a method for the automatic investigation spatial distribution of street vendors based on street-view images and a deep-learning object recognition model. Street-view images were collected at fixed intervals according to the urban road network, and 1,957 images containing one or more vendors were selected through human-machine interaction to establish street vendor label data. To achieve high recognition model accuracy, the category labels were subdivided into four categories: ground stalls, table stalls, tricycle stalls, and small truck stalls, based on the goods carriers used by street vendors. A deep neural-network-based image object detection model based on YOLO v4 was constructed to identify street vendors in the street-view image library, with an average F₁ value of 0.77 and an mAP of 0.67. The accuracy of the model was satisfactory for investigating the number and location of street vendors covering the main roads in the city and then applying a kernel density distribution model to evaluate the spatial distribution pattern of street vendors. Using street vendors in Guangzhou as a case study, the proposed automatic investigation model identified 26,119 street vendors from 3,339,062 street-view images. The results showed that the street vendors were distributed in a multicenter aggregation pattern in the central urban area, mainly concentrated in areas with high pedestrian traffic, such as subway stations and urban villages; their numbers increased as road grades decreases. Street vendors were mainly distributed in areas with medium rents. The proposed method is helpful for performing the efficient, low-cost, and city-scale mapping of street vendors; the results obtained provide suggestions for formulating and implementing spatial governance policies for the informal economy and further provide suggestions for improving and implementing spatial governance policies for open and diverse urban street-view images. The results can be used as a reference for the location preference analysis of practitioners, the exploration of NIMBY syndrome, and the determination of the formalization zone. Although street-view images have an insufficient spatiotemporal coverage, using them to perform street vendor investigations is a low-cost and efficient method compared with the use of traditional investigation methods and data sources. In addition, the method proposed in this article can be coupled with multitask deep learning algorithms to investigate additional dimensions of street vendor information, such as the sex, age, and type of business of street vendors. Relevant research needs to be conducted in the future.