Low efficiency of earth kilns used in the carbonising process of wood to make charcoal has been reported as one of the sources of increasing charcoal wastes in the global south. However, the potential link and approaches of converting charcoal wastes-to-valuable energy and for the environmental health is not well known in Africa. Promoting local community capacity engagement in the production and reutilisation of recycled charcoal wastes at the households’ level is one of important measures to maintain environmental services for sustainability since households make decisions on the type of energy used. This paper, presents an approach of converting charcoal wastes to fuel energy for rural households and environmental health in Kilosa District, Tanzania. To achieve the objective of this research, the primary data were collected through interviews held with 298 randomly selected households, Focus Group Discussions and observations. IBM SPSS statistics version 20 Cross tab tools were used in the data analysis. Results revealed that the conversion of charcoal wastes-to-fuel energy approach used in this research demonstrates the ability of recyclable briquettes made from the locally available charcoal pollutants collected at different stages from earth kilns, to selling centers, improves tree harvest behaviour, adds another fuel energy source through reutilisation, and ultimate reduces pollution at the local level. Thus, the study provides a basis for policymakers to adopt charcoal wastes recycling strategies to address matters related to energy and ultimately enhances environmental health for sustainable development in Tanzania and beyond.

Urban trees are valuable resources for urban areas as they have the capacity to reduce ambient temperatures, mitigate urban heat island effects and reduce runoff of rainwater playing an important role in mitigating the impacts of climate change by reducing atmospheric carbon dioxide (CO2). It also helps to reduce aerial suspended particulate matter, add visual appeal to the urban landscape sequestrating a significant amount of carbon from ambient atmospheric CO2. Carbon storage by urban trees in the ring road area of the Kathmandu Valley was quantified to assess the magnitude and role of urban forests in relation to mitigate the impact of global climate change. A total of 40 sample plots were placed randomly for the detailed carbon assessment. Aboveground and belowground carbon pools were considered in the detailed assessment. Furthermore, quality assurance (QA) and quality control (QC) were maintained through regular monitoring and capacity building of the field crews while collecting the bio-physical data. The assessment recorded a total of 33 different species of plants in the avenue’s plantation sites in ring road. The mean seedling, sapling, and tree density was found to be 2149585 and 185 per hectare. The mean carbon stock per hectare in the avenue plantation of the ring road area was 24.03 tC ha1 and the existing total carbon stock was 7785.72 tC in 2021. Likewise, the total baseline carbon dioxide equivalent (tCO2e) in the avenue plantation was found to be 28573.60 tCO2e. The carbon dioxide emission from the transport sector in the ring road area in a full movement scenario was 312888.00 tCO2e per annum, while the net emissions was 42547 tCO2e. There was a deficit of carbon dioxide in terms of stock by avenue plantations of 14000.8 tCO2e.This study indicates that the existing urban forest plantation is unable to sequestrate or offset the carbon dioxide that is emitted through the transportation sector. Consequently, open spaces like riverbanks and any other public lands, in which urban forests could be developed has to be planned for the green infrastructure and plantation of the multipurpose trees. The distinct values of forests in and around urban areas have to be recognized in the specific policies and plans for the sustainable management of urban and peri-urban forests to meet the adverse impact of global climate change. In addition, this study provides insights for decision-makers to better understand the role of urban forests and make sustainable management plans for urban forests in the cities like in Kathmandu Valley.

Delimiting ecological space scientifically and making reasonable predictions of the spatial-temporal trend of changes in the dominant ecosystem service functions (ESFs) are the basis of constructing an ecological protection pattern of territorial space, which has important theoretical significance and application value. At present, most research on the identification, functional partitioning and pattern reconstruction of ecological space refers to the current ESFs and their structural information, which ignores the spatial-temporal dynamic nature of the comprehensive and dominant ESFs, and does not seriously consider the change simulation in the dominant ESFs of the future ecological space. This affects the rationality of constructing an ecological space protection pattern to some extent. In this study, we propose an ecological space delimitation method based on the dynamic change characteristics of the ESFs, realize the identification of the ecological space range in Qionglai city and solve the problem of ignoring the spatial-temporal changes of ESFs in current research. On this basis, we also apply the Markov-CA model to integrate the spatial-temporal change characteristics of the dominant ESFs, successfully realize the simulation of the spatial-temporal changes in the dominant ESFs in Qionglai city’s ecological space in 2025, find a suitable method for simulating ecological spatial-temporal changes and also provide a basis for constructing a reasonable ecological space protection pattern. This study finds that the comprehensive quantity of ESF and its annual rate of change in Qionglai city show obvious dynamics, which confirms the necessity of considering the dynamic characteristics of ESFs when identifying ecological space. The areas of ecological space in Qionglai city represent 98307 ha by using the ecological space identification method proposed in this study, which is consistent with the ecological spatial distribution in the local ecological civilization construction plan. This confirms the reliability of the ecological space identification method based on the dynamic characteristics of the ESFs. The results also show that the dominant ESFs in Qionglai city represented strong non-stationary characteristics during 2003-2019, which showed that we should fully consider the influence of the dynamics in the dominant ESFs on the future ESF pattern during the process of constructing the ecological spatial protection pattern. The Markov-CA model realized the simulation of spatial-temporal changes in the dominant ESFs with a high precision Kappa coefficient of above 0.95, which illustrated the feasibility of using this model to simulate the future dominant ESF spatial pattern. The simulation results showed that the dominant ESFs in Qionglai will still undergo mutual conversions during 2019-2025 due to the effect of the their non-stationary nature. The ecological space will still maintain the three dominant ESFs of primary product production, climate regulation and hydrological regulation in 2025, but their areas will change to 32793 ha, 52490 ha and 13024 ha, respectively. This study can serve as a scientific reference for the delimitation of the ecological conservation redline, ecological function regionalization and the construction of an ecological spatial protection pattern.

Abstract: By studying the structural characteristics and carbon storage of the mangrove island ecosystem in the 
Beibu Gulf, this study provides a scientific basis for mangrove ecological compensation in the coastal areas of 
Guangxi, South China Sea. On the basis of the unmanned aerial vehicle remote sensing images and a sample plot 
survey, the object-oriented multi-scale segmentation algorithm is used to extract the mangrove community type information, and one-way analysis of variance is conducted to analyse the structural characteristics of the mangrove 
community. The carbon storage and carbon density of different mangrove ecosystems were obtained based on the 
allometric growth equation of mangrove plants. The analysis yielded four main results. (1) The island group covers 
about 27.10 ha, 41.32% (11.20 ha) of which represents mangrove areas. The mangrove forest is widely distributed 
in the tidal flats around the islands. (2) The main mangrove types were Aegiceras corniculatum, Kandelia obovata + 
Aegiceras corniculatum, Avicennia marina + Aegiceras corniculatum and Avicennia marina communities. (3) 
Amongst the mangrove plants, Avicennia marina had the highest biomass (18.52 kg plant–1), followed by Kandelia 
obovata (7.84 kg plant–1) and Aegiceras corniculatum (3.85 kg plant–1). (4) The mangrove carbon density difference 
was significant. Kandelia obovata had the highest carbon density (148.03 t ha–1), followed by Avicennia marina
(104.79 t ha–1) and Aegiceras corniculatum (99.24 t ha–1). The carbon storage of the mangrove island ecosystem 
was 1194.70 t, which was higher than in other areas with the same latitude. The carbon sequestration capacity of 
the mangrove was relatively strong.

Against the backdrop of global environmental changes and the ongoing advancement of China's ecological civilization, the natural resources science must deepen its theoretical foundations and refine its academic system to address pressing challenges such as population-resource conflicts. Based on a review of the development trajectory of natural resource science, this paper focuses on the interaction and coordination between "space" and "elements" and proposes a disciplinary framework for natural resource planning centered on the "space-element-planning" triad. The proposed framework takes "spatial positioning-element allocation-planning coordination" as its logical starting point and builds the disciplinary content system around three key dimensions: revealing spatial patterns, optimizing element configurations, and constructing spatial support. Looking ahead, the development of natural resource planning should be guided by indigenous knowledge innovation, supported by interdisciplinary curricula, and driven by major scientific and technological missions. This will promote the establishment of a robust discipline of natural resource planning that supports the unified management of natural resources and territorial spatial governance, contributing to the realization of Chinese-style modernization characterized by harmony between humanity and nature.

Based on the theory of cultural ecosystem services (CESs) and the simultaneous development of five educations, this study constructs a comprehensive framework to elucidate the mechanisms among landscape education, CESs values, and natural resources teaching. It compiles expert evaluations of illustrations from middle school geography textbooks and a collection of study-tour itineraries for Gansu province. Using methods including categorical statistics, kernel density estimation, and MaxEnt model prediction, the study assesses the CESs values of natural resources featured in middle school geography curricula and Gansu study sites, and explores pathways through which value evaluation can advance natural resources teaching. Findings indicate: (1) Digital landscapes convey the digital CESs values in theoretical teaching through multimedia courseware, textbook illustrations, and other forms. Students perceive the physical CESs values via observation, experience and research. The values of CESs provide a pivotal basis for selecting teaching materials and field sites. (2) The illustrations in chapters such as "Resources Security and National Security" carry high value. Mixed multiple illustrations layouts better express educational and spiritual values. Chapter cover illustrations convey aesthetic values, and educational and spiritual are strongly linked. Values evaluation informs textbook revision through the selection of graphic and textual cases, innovative arrangement methods, optimized visual effects, and exploration of ideological and political elements. (3) Study-tour courses in Gansu show overall agglomerative spatial distribution. Lanzhou city and surrounding counties are the main high-value areas for five types of CESs. The high-value areas in the Hexi Corridor are concentrated in oases and cities. Value distribution is highly correlated with the density of primary and secondary schools in the region. Values assessment guides study-tour product development and practical education-based construction. The research has practical significance in refining teaching strategies and objectives across educational levels, optimizing teaching resources, and linking of theory with practice in teaching.

Land-sea integration is the core value orientation for the synergistic utilization of terrestrial and marine space and resources in China. To construct a coastal human settlement environment system featuring human-land (sea) interaction under the multidimensional goals of land-sea integration, this paper proposes the concept of the "Key Zone of Land-Sea Integration" and its spatial structure of "supporting zone-core zone-associated zone-hinterland zone". The Key Zone of Land-Sea Integration implements the research perspective of the coastal human settlement environment system in terms of scope definition, hierarchical structure, research priorities, and development dimensions. It follows the research approach of "spatial structure-geomorphic pattern-ecological network-human settlement order", couples the multidimensional values of "ecology-economy-space-culture-society", and puts forward key research issues. Specifically, in scope definition, it clarifies the spatial scope integrating land and sea, covering both coastal areas and their adjacent terrestrial and marine extensions. In hierarchical structure, it establishes a multi-level system to adapt to analyses and management at different scales. In research priorities, it focuses on the dynamic interactions between human activities and the natural environment within the zone. In development dimensions, it emphasizes the balance among economic growth, social progress, and ecological protection. Focusing on the integration of human-land (sea) interaction and the integration of land-sea multidimensional values at the urban scale from the perspective of the coastal human settlement system environment, the Key Zone of Land-Sea Coordination proposes clear spatial objects and carriers. It will further promote the integration of land-sea coordinated territorial spatial planning and governance, break down traditional barriers between land and sea management, and facilitate high-quality development of coastal human settlement by guiding rational spatial layout, efficient resource utilization, and harmonious coexistence between human and nature. Thus, it provides theoretical support and practical guidance for advancing systematic management of coastal areas and optimizing the sustainable development pattern of coastal human settlement.

International digital infrastructure represented by submarine cables has important strategic value in information transmission, economic and trade stability, and military security, and can provide solid support for the spatial selection of China's overseas strategic pivots (COSPs). Based on the theoretical framework of spatial selection of COSPs and the distribution pattern of global submarine cable network, we identified global Internet gateways and then screened COSPs at the regional, national and teleport scales. The results show that: (1) Overseas strategic pivot is further extension of Internet gateway, which endows the latter with a pivot attribute and strategic meaning on the basis of its connotation. The identification logic of COSPs based on submarine cable network follows the three-level spatial scale of ''region-country-teleport'', and geopolitical theory, new state space theory and location theory respectively dominate the spatial selection of COSPs at higher scale, mesoscale and lower scale. They each have their own focus and are nested with each other, forming a logical framework of the spatial selection of COSPs based on submarine cable network. (2) The global submarine cable network exhibits a distinct spatial imbalance, a pattern further diversified by the cumulative effects of scale on node distribution. However, regardless of the scale, the global submarine cable network has formed a ''one heart, three poles, three corridors'' pattern with the rimland of the Eurasian continent as the heart, the United States, the United Kingdom and Singapore as the three poles, and the three main corridors spanning the North Atlantic, the southeastern and the southwestern sea area of the Eurasian continent. (3) The spatial selection results of COSPs have geographical proximity and similarity, mainly distributed in six strategic zones, namely East Asia-Southeast Asia strategic zone, Persian Gulf-Red Sea strategic zone, Mediterranean-Europe West Coast strategic zone, Africa West Coast strategic zone, Caribbean strategic zone, and Eastern North Pacific strategic zone, presenting a ''core-expansion-periphery'' distribution pattern. The results can enrich the research framework of submarine cable and strategic pivot, providing theoretical reference and policy inspiration for expanding China's overseas interests.

With the emergence of new materialism, political geography has undergone a "volume turn" in an attempt to resolve the increasingly prominent dichotomy between nature and humanity. Volume studies oppose the flattening and static nature of traditional geopolitical research. Instead, they advocate starting from the materiality of the Earth system, emphasizing the significant impact of the three-dimensionality and fluidity of space on human activities and even emotions. This has sparked a wave of research on Earth politics in relation to volume politics and power dynamics. At the level of empirical research, the "volume turn" focuses on the three-dimensional aspects of geopolitics, its interaction with geophysical politics, as well as the sense of immersion and emotional atmosphere of humans within the Earth surface system. It aims to uncover the operations of politics, power, and emotions under the influence of the Earth system. On the one hand, the "volume turn" challenges the traditional territorial concept based on planarism, greatly expanding the scope of research in political geography. On the other hand, it broadens the human-environment relationship from an anthropocentric perspective to a comprehensive view of the human-Earth system. It bridges the gaps between "human and non-human" and "nature and society," emphasizing the embodied interaction between the human body and the Earth system. Undoubtedly, the "volume turn" will contribute to the expansion of research horizons and the integration of research themes in Chinese geography.

This study analyzes the development of the discipline of human geography in China over the past 40 years, based on projects funded by the National Natural Science Foundation of China (NSFC) from 1986 to 2023. The analysis focuses on research directions and themes, the hosting institutions and their spatial distribution, as well as the structure of high-level talents. This paper primarily employs methods such as keyword cloud analysis, probability density distribution analysis, and spatial analysis. The findings are as follows: (1) Although the number and financial volume of funded projects have grown rapidly, human geography remains at a disadvantage in terms of scholarly influence and the magnitude of funding support. (2) The majority of approved projects and funds are concentrated under the application codes for Urban and Rural Geography (D0109) and Economic Geography (D0108), though growth in these areas has been limited in recent years. Promising areas of focus include cultural geography, political geography, and behavioral geography. (3) New research topics have emerged, such as spatiotemporal behavior and quality of life, social space and mobility, innovation networks, city networks, rural revitalization, geopolitics, and carbon reduction. (4) The distribution of approved NSFC projects in human geography generally follows a Pareto distribution and is predominantly located east of the Hu Line. (5) There are relatively few high-level talents in human geography in China, with an unbalanced gender ratio. To advance the field, we propose to raise human geography's profile in interdisciplinary dialogue, to consolidate disciplinary consensus, to articulate key research priorities and assessment frameworks, address developmental disparities among subfields, and prioritize groundbreaking research agendas. The study underscores key unresolved issues in the discipline's governance and financing, including the generality-specificity spectrum in knowledge generation, and reconciling inter-direction competition with distributive justice in resource allocation. The research advances scholarly understanding by documenting funding-driven development patterns in Chinese human geography while addressing dual challenges of international disciplinary recognition and domestic academic consensus-building.

The spatial restructuring of large Chinese cities has exacerbated internal spatial differentiation and social segregation, resulting in disparities in the distribution of environmental risks across social groups and regions. This has negatively impacted the health and well-being of urban residents. This study analyzes the socio-spatial disparities in environmental risk distribution in Shanghai, Guangzhou, and Chengdu using pollution discharge permit data and census data, with ArcGIS spatial analysis methods. Principal component analysis is then applied for dimensionality reduction to capture the characteristics of urban spatial restructuring. Interaction term models are applied to analyze the intrinsic connections between environmental inequality and the urban spatial restructuring process. The findings reveal that individuals with lower education levels and migrant populations are exposed to greater environmental risks, with environmental inequality increasing from the city center to the periphery. The spatial variations in environmental inequality across the three cities can be attributed to their respective urban spatial restructuring processes and development trajectories, resulting in three distinct patterns of environmental inequality: minimal impact, localized improvement, and environmental deprivation. The study draws on Spatial Production Theory and Rawls' Theory of Justice to elucidate the evolution of environmental inequality in spatial differentiation within the context of urban spatial restructuring, emphasizing the shift from capital-driven spatial production to government-led social justice practices. It is suggested that when formulating and implementing strategies to promote environmental justice and sustainable urban development, the global and dynamic nature of urban space development should be considered to ensure equitable sharing of environmental benefits across all regions and social groups.

Three-dimensional fine characterization of soil pollutant distribution is critical for the implementation of precision remediation and scientific decision making in the management of contaminated sites. This review systematically examined key issues and research progress in this field through a trinity framework of non-stationarity decoupling, data bias correction, and model selection. We identified the spatial non-stationarity of pollutant concentrations and the inherent biases in sparse borehole data as two fundamental constraints that affect the accuracy of existing three-dimensional characterization models and the reliability of characterization results. We first analyzed the formation mechanisms and types of non-stationarity and discussed non-stationarity quantification and decoupling methods. Second, we summarized the principal sources of sampling bias in the collection of sparse biased drilling data and its bias correction method system. We also assessed the adaptability of different models to biased data and possible improvement. Third, we compared the advantages and limitations of the three predominant modeling paradigms (geostatistical, machine learning, and geochemical process models), analyzed the discrepancies and uncertainties in three-dimensional characterization model selection, and stressed the need for constructing a multi-source data-driven high-precision three-dimensional characterization system based on the trinity relationship framework. Finally, in combination with the development of intelligent decision-making technologies, we prospected the potential application of three-dimensional characterization technology in pollution diagnosis, risk assessment, and sustainable remediation. We also emphasize the potential value of model integration and dynamic optimization in soil pollution control. This methodological synthesis provides a reference for improving the accuracy of three-dimensional characterization of soil pollution distribution in complex sites and digital governance mode.

Terraced farmland is a unique agricultural landscape and high-quality farmland resource in mountainous areas, with great production and ecological functions, which makes it a valuable livelihood asset for rural households. As a type of farmland resource, the high-quality of terraced farmland originates from the substantial investment of labor force and materials in land improvement processes such as terracing projects, which results in higher "landesque capital". The economic essence of landesque capital is land appreciation. In recent years, the phenomenon of farmland asset devaluation has been widespread in mountainous areas, yet how the landesque capital value of terraced farmland change remains unclear. Therefore, based on land capital theory, this study clarifies the definition of the landesque capital value of terraced farmland, constructing a comprehensive diagnostic framework from the dual perspectives of land economic productivity and land marginalization. Using data from national rural household surveys and literature synthesis in China's mountainous areas, the study reveals the trends and regional differences of landesque capital value. The findings demonstrate that in recent decades, the landesque capital of terraced farmland in China has devalued, with the trend being particularly pronounced in the eastern region. From 1996 to 2020, the differential rent reflecting the landesque capital value of terraced farmland decreased from 793.2 yuan per ha to 441.88 yuan per ha (a 44.29% drop), based on 1995 constant prices. The grain yield increase effect of terraced farmland relative to sloped farmland has been declining, with the rocky mountainous areas in Northern China showing a more significant downward trend than the Loess Plateau region. The economic benefits derived from the landesque capital of terraced farmland are increasingly unable to cover the costs of maintaining their unique functions. Therefore, it is recommended to actively explore optimal utilization approachs for existing terraced farmland while cautiously implementing new terracing projects in China's mountainous areas.

The changes in the natural-artificial dualistic water cycle system have triggered the inconsistency of hydrometeorological time series. Continuing to use traditional frequency calculation methods would affect the accuracy of water resource planning and flood-drought management decisions, underscoring the need for (in)consistency testing before performing hydrological calculations. To address the misjudgement issues of current methods, this study proposes a hydrological (in)consistency testing method (CT) based on correlation coefficients. The CT method applies a discrete wavelet transform to extract high-frequency pure random components from the original time series, then calculates the correlation coefficients between these components and the original time series to determine (in)consistency. Statistical experiments indicate that the CT method significantly reduces false positive rates compared with traditional methods like the Bartels test. Its accuracy and stability improve as the time series length increases, making it especially effective at identifying inconsistent time series. These promising results confirm that the CT method is a valuable tool in (in)consistency test, ensuring robust and reliable outcomes. A case study of the surface water resources amount modulus coefficient time series of 10 major river basins in China (1956-2020) shows that surface water resources in the Southeastern, Yangtze, Huaihe, Pearl, and Southwestern river basins are consistent. In contrast, the Songhua, Haihe, Yellow, Liaohe, and Northwestern river basins display pronounced inconsistency characteristics. Existing studies, based on external driving factors such as climate change and human activities, have validated the inconsistency of hydrological time series in regions like the Songhua River Basin, indirectly confirming the effectiveness of the CT method. For consistent time series, consistent hydrological frequency analysis can be directly applied, whereas for inconsistent time series, researchers should analyze the characteristics of inconsistent components or conduct inconsistent hydrological frequency calculations. These approaches aim to predict and plan for potential risks, thereby providing robust support for scientific water resource management decisions.

The innovation network of digital technology plays a significant role in reshaping innovation spaces and developing new quality productivity. This study explored the dynamic mechanism of impact of the endogenous structure of China's intercity digital technology innovation network, urban innovation endowments, and multidimensional boundary effects from the perspective of intercity collaboration between innovation entities, employing a temporal exponential random graph model (TERGM). The results indicate that: 1) In terms of the characteristics of spatial-temporal change, the innovation network exhibited a "dense in the east and sparse in the west" pattern, forming a diamond-shaped structure with five major urban agglomerations as endpoints. The core nodes of the network were primarily economic and technological centers within these urban agglomerations, and the network displayed regional imbalances. As the network evolved, the mode of connectivity shifted from long-distance dominance to a model that balanced nearby diffusion with small-scale, community-based innovation. The overall structure of the network demonstrated a certain degree of stability, with core nodes remaining unchanged, reflecting a situation where core technological cities within urban agglomerations drove innovation development in other regions. Additionally, there was a phenomenon of numerous factions existing within different regions, urban agglomerations, and provinces. 2) With regard to the mechanism of influence, the preferential linking effect of endogenous structures hindered network growth through the formation of "the strong gets stronger, the weak gets weaker" polarization. Closure and mediation effects promoted network change by facilitating link transmission among nodes and fostering closed innovation groups, indicating that the network exhibited path dependence. The expansion effect of urban innovation endowments and the matching effect of similarities and differences drove network change. Intercity relationship variables showed that geographical distance and administrative boundaries significantly obstructed network development. This study visualized the virtual aggregation of digital technology innovation elements from a geographical perspective and examined the driving mechanisms of the endogenous structure within networks on digital technology innovation. It provides an empirical support for the macro integration of virtual and geographical agglomerations in innovation spaces.

Under the background of global climate change and intensified human activities, China's hilly and mountainous areas, as the core implementation area of the "beautiful countryside construction" strategy and the key development area of transportation arteries and hydropower hubs, have become the regions with the most complex disaster-breeding environment for flash floods, the most significant disaster-causing effects, and the highest exposure of disaster-affected elements. However, existing research lacks a systematic collation and summary of the framework of flash flood disaster prevention and control theory and technology under the new situation of frequent extreme weather events. This review article started from the spatial characteristics of flash flood disasters in China and the major deployment concepts of national prevention policies, compared international research results, comprehensively examined the important progress and practical achievements of flash flood water-sediment processes and theories and prevention and control technology research, analyzed the impact of climate change on flash flood disasters and the future trend of disaster risks and proposes five scientific challenges for flash flood disaster prevention and control under climate change. It also proposed five targeted preventive measures and suggestions from the perspectives of water-sediment process mechanism research, forecasting and warning technology, comprehensive prevention and control technology, and capacity building. aiming to continuously strengthen research on the basic theory and prevention principles of flash floods in China, promote the intelligentization, digitization, and modernization of the comprehensive defense capabilities and systems against flash floods, and comprehensively enhance the new quality productivity of disaster prevention, mitigation, and relief in the new era, as well as the resilience level of urban communities and engineering construction.

The co-occurrence of droughts at multiple time scales in the water source area (Upper Hanjiang River, UH) and receiving area (northern North China, NNC) of the Middle Route of the South-to-North Water Diversion project highlights the need to identify common climatic drivers for these concurrent phenomena. Using reconstructed drought/flood grade data and sunspot series from 1700 to 2023, this study analyzed the correlations of droughts/floods in the Upper Hanjiang River and northern North China with sunspots at 11-, 30- and 50-year scales. The results show that the correlation between sunspots and droughts/floods in these two areas varied in stages over time. During high sunspot periods, the frequency of extreme drought events increased in both areas. The phase change of the correlation between sunspots and droughts/floods in the Upper Hanjiang River and northern North China significantly influenced the shift in the drought-flood correspondence between the two areas. When droughts/floods in the Upper Hanjiang River and northern North China align with or oppose sunspot variations, the droughts/floods in the two areas are predominantly positively or negatively correlated. Both droughts/floods in the Upper Hanjiang River and northern North China as well as sunspots share inter-annual cycles of about 2-4 years, inter-decadal cycles of about 11-12 years, and multi-decadal cycles of about 20-30 years and 50 years. Sunspot variations may influence the droughts and floods in these two areas across multiple time scales. Additionally, when sunspots increase significantly and abruptly, the Upper Hanjiang River and northern North China tend to be more drought-prone.

The spatiotemporal evolution of settlements during historical periods is of great significance for a better understanding of past environment changes, land use, and the dynamics of human-land relationships. Chinese historical documents contain abundant information on settlements, serving as an important proxy for the study on the evolution settlements over the past century. Historical documents typically employ place names to record the spatial location of settlements, but the existing historical place names spatial databases often fall short in automating the precise localization of micro-scale place names, such as settlements, which in turn impedes the advancement of research on the spatial reconstruction and spatiotemporal evolution of these historical settlements. This study focuses on the automated matching method of historical settlement place names, utilizing Suzhou Prefecture during the late Qing Dynasty (1820-1911) as the research area. It selected 11340 settlement place names and their associated primary-level division data extracted from local chronicles, and combined contemporary place names matching techniques to construct a conceptual model for correlating ancient and modern place names. The study identifies characteristics of place names evolution, establishes rules for place names matching, and proposes an algorithm for the aggregation and matching of settlement names predicated on similarity metrics, thereby accomplish the spatial reconstruction of historical settlements within the research area. On this basis, the spatial distribution and urban-rural relationships of the reconstruction results were analyzed. The results indicated that approximately 98% of the settlements, relative to the total number documented in the literature, were reconstructed using an automated place names matching method. The spatial resolution of the reconstruction was approximately 1.4 km × 1.4 km, and the consistency between the automatic matching outcomes and the manually verified results was about 96%. During the late Qing Dynasty, the distribution of settlements in the study area exhibited agglomerative characteristics, with a hierarchical structure of settlement networks centered on the western suburbs of Suzhou city. However, urban-rural connections within the network were sparse. The findings from this study have enhanced the technical methods for the spatial reconstruction of historical settlement space and deepened the scientific understanding of the characteristics and influencing factors of long-term settlement evolution.

In the context of the Fourth Industrial Revolution and a new wave of technological advancements, integrating technological innovation resources and accelerating strategic emerging industries have become crucial for promoting high-quality economic development. Industrial innovation networks are critical in this landscape, as they enable cities to participate in innovation networks that facilitate the absorption of external knowledge, technologies, and market information, which promotes regional technological innovation. In this study, we focused on the rare earth industry in China, which supports innovation within strategic emerging fields, particularly in technological breakthroughs. Patent collaboration data from three critical stages of the value chain (i.e., mining and smelting, material processing, and end-use applications) were used with social network analysis and Quadratic Assignment Procedure regression methods to explore the spatial characteristics and influencing factors of the innovation network at different stages. The primary goal of the study was to determine the structural differences in innovation networks within an industry and how these differences are influenced by the functional roles of the value chain. The findings indicate that the scale of the innovation network in China's rare earth industry expands progressively along the value chain, particularly in the end-use application stage, in which the density of connections among the participants increases considerably, resulting in a "small world" characteristic. Moreover, the innovation network in the mining and smelting stage exhibits a north-south differentiation pattern that is consistent with the geographical distribution of China's rare earth resources (i.e., light rare earths in the north and heavy rare earths in the south). In contrast, the material processing stage exhibits a radial pattern dominated by national innovation centers such as Beijing and Shanghai, whereas the end-use application stage exhibits a "triangular" pattern centered on cities with concentrated strategic emerging industries, highlighting the importance of regional innovation ecosystems. Analysis of the influencing factors indicates that the innovation network is primarily affected by social and institutional proximities, as well as the innovation output capacity. Notably, the impacts of resource agglomeration and openness to foreign markets vary among different stages of the value chain. For example, resource agglomeration is significant in the material processing stage but has a lower impact in the end-use application stage, where the level of openness to foreign markets is crucial for driving innovation. Building on existing research on industry-wide innovation networks, this study investigated the internal differences in innovation networks and mapped value-creation processes within the rare earth industry. The findings indicate that marked spatial differences exist among the mining and smelting, material processing, and end-use application stages, which are closely related to the value processes and resource endowments in each stage. In addition, the findings obtained herein provide theoretical and empirical support for understanding spatial innovation activities along the industrial value chain. We offer policy recommendations for optimizing the spatial configuration of the innovation network in China's rare earth industry, with the goal of enhancing its competitiveness in high value-added sectors and supporting the nation's transition to a more innovation-driven economy.

Counties in the Yangtze River Delta face considerable pressure from industrial transformation. In addition, an enclave economy has substantial value for enhancing county-level innovation capacity and advancing industrial upgrades. Enclave economies facilitate the flow of innovation resources into counties and strengthen collaborative innovations between counties and central cities. However, the effectiveness of these innovations is constrained by factors such as benefit-sharing mechanisms and each county's capacity to absorb innovation resources. Thus, systematic empirical research is urgently required to evaluate their impacts. This study focused on Jiangsu and Zhejiang provinces, where exploration of the enclave economy in the Yangtze River Delta region has been the most advanced. Using a multi-period Difference-In-Differences (DID) model, we examined how establishing enclave industrial parks from 2001 to 2022 influenced county-level innovation outputs, as well as the heterogeneity of these impacts across forward and reverse enclave models and different county types. The findings indicate that the enclave economy exerted an overall positive impact on county-level innovation, and a larger number of enclave parks corresponded to more pronounced increases in innovation. Multiple robustness tests confirmed the reliability of these results. In addition, nationally ranked top-100 counties demonstrated considerably higher susceptibilities to the positive effects of enclave economies compared with those of non-top-100 counties, likely because relatively developed counties have better environments to support innovation, which facilitates the absorption and transformation of innovation resource flows triggered by enclave park construction. Forward enclaves, which are characterized by earlier initiation and more mature mechanisms, had a markedly superior effect on enhancing county innovation compared with that of reverse enclaves, even though reverse enclaves theoretically exert a more direct and effective impact on county-level innovation. Enclave parks co-constructed by national ministries and local governments, by local governments alone, or between development zones were also more likely to positively influence county innovation than those involving other entities. This may occur because these actors primarily exist within the public sector and share homogenous policy agendas and preferences; thus, collaboration among them is more conducive to reducing communication and coordination costs, thereby enhancing their role in boosting county-level innovation. These results suggest that future efforts should prioritize enhancing the capacities of less-developed counties to absorb innovation resources and direct more policy support towards innovative models, such as reverse enclaves and university-satellite industrial parks. Less-developed counties should address their own developmental foundations and capacity to accommodate innovative resources in the construction of enclave economies, avoid impatience, and emphasize nurturing an environment conducive to innovation. However, compared with forward enclaves, which are characterized by industrial gradient transfer, reverse enclaves have stronger attributes for technological innovation, aiming to promote county-level industrial transformation by incubating innovative enterprises. Given reverse enclaves' shorter construction period and associated inadequate mechanism exploration, it is necessary to provide more policy support and assess their actual effects over a longer timescale. Similarly, because universities are a crucial component of the triple-helix model of innovation, enclave parks co-constructed with universities hold greater potential for boosting county-level innovation than those co-established with other actors. Therefore, barriers related to park management, technology transfer, and funding support for universities and research institutions should be addressed promptly to amplify their spillover effects on county-level innovation activities.