Geopolitics of energy transition has increasingly become the frontier and hot research area of world energy geography and global political science. Different historical periods are characterised by obvious differences in energy connotations, attributes, and geopolitical characteristics. In the new energy era, energy geopolitics becomes more diversified, complex, and comprehensive. In this paper, we compare the geopolitical characteristics of energy in the fossil fuel and renewable energy periods, and provide an overview of current study trends in new energy geopolitics. Recent research shows that the global energy transition will intensify the reconstruction of geopolitical patterns, change the relationship between geopolitical security and conflict dominated by traditional energy security, alter the role of different countries in global energy geopolitical games, reshape national energy relationships formed in the traditional oil and gas era. In addition, geopolitics will be affected by new energy technologies, availability of key rare materials, and energy cybersecurity measures. Despite considerable attention to this research topic, the likely geopolitical impact of energy transition remains uncertain, and there is still room for the development and improvement of the theoretical framework, technical methods, and research perspective. Looking forward to the future, the research into geopolitics of energy transition urgently needs to strengthen its theoretical basis and rely on the scientific and quantitative methods. The practical conclusions of the research into geopolitics of energy transition should strengthen major national energy security decisions, explore the geographical effect of energy transition, and determine the impact of energy transition on energy security. Research into geopolitics of energy transition should be carried out taking into account international academic frontiers such as climate change, “carbon peak” and “carbon neutral” goals, and global energy governance, to enrich the research perspective of world energy geography.
Cross-domain research and development has prevailed in regional transformation and disruptive innovation in the last 15 years. Recently, a new concept, termed combinatorial knowledge bases (CKBs), offers insights into combining knowledge dynamics and is considered a good approach to explore recombinant innovative activities. Here, we review the literature on CKBs in Western economic geography, and we introduce a research agenda for CKBs in China’s economic geography. Concerning the latter, four aspects are elaborated: the co-evolution of the innovation chain and industrial chain, the geography of innovative activities, innovative entrepreneurship and new path development, and innovation system reconfiguration. This paper contributes to theoretical studies of China’s geography by linking CKBs to Chinese-specific phenomena.
As a kind of large-scale connectivity infrastructure, submarine cables play a vital role in international telecommunication, socio-economic development and national defense security. However, the current understanding about the spatial pattern of global submarine cable network is relatively limited. In this article, we analyze the spatial distribution and connectivity pattern of global submarine cables, and identify their strategic pivots and strategic channels. The main conclusions are as follows: (1) The spatial distribution of global submarine cables is significantly unbalanced, which is characterized by the facts that the distribution of submarine cable lines is similar to that of sea lanes, and the agglomerations of landing stations are distributed unevenly along the coastline. (2) The connectivity pattern of global submarine cable network has a significant scale effect. At the micro, meso and macro scales, the connectivity structure presents chain model, cluster model and hub-and-spoke model, respectively. (3) The distribution of strategic pivots and strategic channels shows a pyramidal hierarchical feature. Singapore ranks highest among all the strategic pivots, while the Gulf of Aden and the Strait of Malacca rank highest among the strategic channels. Based on the identification of strategic pivots and channels, six strategic regions have been divided, which face various network security risks and need special attention and vigilance.
Exploring the utilization effect of water-land resources under the evolution of dietary patterns is of great significance in achieving sustainable global food consumption and the effective allocation of national resources. Our selected study area was China, a country with rapidly changing dietary consumption patterns, and the research period was between 1987 and 2020. Based on the material called Chinese Dietary Guidelines 2021, this study introduced the “virtual water” and the “virtual land” to quantify the utilization effect of water-land resources under the evolution of Chinese dietary patterns. Results showed that the dietary patterns gradually changed from “cereal-vegetable-based consumption” to “diversified consumption”. Food consumption’s total water footprint (WF) increased from 471.1 Gm3 in 1987 to 848.8 Gm3 in 2020, with a growth rate of 80.2%. Moreover, the total land requirement for food (LRF) increased from 88.8 Mha in 1987 to 129.9 Mha in 2020, with a growth rate of 46.3%. Furthermore, the meat consumption was the major contributor to the increase in total WF (104.0%) and LRF (102.1%). In contrast to the balanced diet pattern, there was no waste of water-land resources consumption for the food consumption of urban-rural residents in China between 1987 and 2020. However, the consumption of water resources would gradually approach the resource cost under the balanced diet patterns. It would eventually break through the critical value and reach the state of resource waste. In addition, the findings showed that urban residents’ waste rate of water-land resources for meat consumption increased by 142.3% compared with that in 1987. The research results can provide scientific guidance for resolving the food crisis under the supply of water-land resources in China and have an essential reference for national food security and sustainable development of resources and environment.
Relatively coordinated development among cities can typically promote the integration of the whole urban agglomeration, while urbanization of land has been found important to economic development in developing countries. Numerous studies have measured the urban land expansion in urban agglomerations. However, urban land spatial inequality under a specific spatial structure remains poorly understood. Here, we combined the β-convergence model and the core-periphery structure to explore the dynamic changes in urban land spatial inequality in urban agglomerations. The Yangtze River Delta Urban Agglomeration (YRDUA) in China was selected as the study area. Indicators of urban land have been applied in conjunction with a modified conditional β-convergence model, while the existence of the core-periphery structure was tested by analyzing coefficients of the control variable. The results show that although the spatial inequality of urban land area had decreased during 2000-2020, the whole YRDUA had still shown an obvious core-periphery structure. Compared with urban land area, the spatial inequality of urban land economic density and population density had decreased more rapidly, and the core-periphery structure was less obvious. Our findings can help to improve our current understanding of urban agglomeration and serve as a scientific reference for the coordinated development of urban agglomerations.
Developed here is an integrated framework for identifying production-living-ecological space (PLES) quantitatively at grid scale from the perspective of multifunction land use, and 25 compound space types are classified to highlight the multiple functions of PLES. As a typical mountainous city in northern Hebei province, Zhangjiakou is used as a case study, and the results show that more than 80% of the land space in Zhangjiakou has remarkable triple functionality. The living-dominated space and the production-dominated space are distributed mainly in the valleys of the Yanghe, Sanggan, and Huliu rivers and have obvious spatial consistency, while the ecological-dominated space is concentrated mostly at the eastern Yanshan Mountains and southern Taihang Mountains and complements the other two types of space. The former two are spatially fragmented, while the latter has been expanding to the periphery over time. From 1990 to 2015, the ecological-dominated space has increased the most by 1555.02 km2, while the living-dominated space has increased the least by 816.79 km2. The types of PLES are more diverse in the medium and low mountains and the areas with gentle slope, and the influencing factors include natural ecological environment, socioeconomic development, human consumption demand, and institutional policies. Therefore, these findings can mitigate conflicts among PLES in mountainous and similar areas, and promote the balanced development of land space.
Suitable spatial morphology of cultivated land is a basic requirement for sustaining agricultural economic development in mountainous areas. Coordinated development efficiency of cultivated land spatial morphology and agricultural economy (CECA) is of great practical significance to measure the efficiency of cultivated land use, and thereby promote regional rural revitalization. However, few studies to date have focused on coordinated development efficiency between cultivated land use and agricultural economy in mountainous areas from the perspective of cultivated land spatial morphology. Thus, the present study explores CECA with this focus using the data envelopment analysis method, and analyzes the key influencing factors via a geographical detector model in 16 counties in western Hubei province. The results show the following: (1) CECA exhibits significant spatial heterogeneity that is high in the south of the study area and low in the north; (2) scale efficiency is the primary limiting factor for CECA; (3) the insufficient output of cultivated land use mainly restricts CECA in the south of the study area, while individual county in the north suffered from input redundancy and insufficient output; and (4) population density in the southern region has the most significant effect on CECA, and gross domestic product has the greatest impact in the northern region. The results contribute to the derivation of specific measures by which to promote cultivated land use efficiency and sustainable development of the social economy.
The middle reaches of the Yellow River represent an important area for the protection and development of the Yellow River Basin. Most of the area of the river basin is within the Loess Plateau, which establishes it as a fragile ecological environment. Firstly, using high-resolution data of land use in the watershed from the past 30 years, landscape ecological risk (LER) sample units are defined and an ecological risk index (ERI) model is constructed. Kriging interpolation is used to display the LER spatial patterns, and the temporal and spatial evolution of risk is examined. Secondly, the spatial evolution of land use landscape change (LULC) is analyzed, and the correlation between land use landscape and ecological risk is discussed. Finally, Based on the LER model, a risk-based minimum cumulative resistance (MCR) model is established, and a comprehensive protection and management network system for the ecological source-corridor-node system designed. The results suggest that in the past 30 years, LER has a high spatial correlation and areas with extremely high ecological risks are concentrated in northwest and southeast areas of the region, of which the northwest area accounts for the highest proportion. Risk intensity is closely related to the spatial pattern of land use landscape. ERI values of forestland, grasslands, and unused land and farmland are low, medium, and high, respectively. The trend of risk evolution is “overall improvement and partial deterioration”. Man-made construction and exploitation is the most direct reason for the increase of local ecological risks. The high ecological-risk areas in the northwest are dominated by deserts which reduce excessive interference by human activities on the natural landscape. Recommendations are: high-quality farmland should be protected; forestland should be restored and rebuilt; repair and adjust the existing ecosystem to assist in landscape regeneration and reconstruction; utilize the overall planning vision of “mountain, water, forest, field, lake, grass, sand” to design a management project at the basin scale; adhere to problem-oriented and precise policy implementation.
Spatial and temporal changes in ecosystem services (ESs) are driven by two types of factors: environmental factors and trade-offs/synergies between services. In the ecological conservation red line (ECRL) area, in which national ecological security and social sustainable development are guaranteed, it is particularly important to clarify the driving mechanism of ESs for the management of ecosystems. In this study, soil conservation, water yield, and carbon sequestration in Beijing’s ECRL area are quantified, and GeoDetector is used to identify the factors influencing the trade-offs/synergies between ESs. Moreover, partial correlation analysis is used to calculate the net trade-offs/synergies and compare them with the extent to which environmental variables contribute to ESs. The results are as follows: environmental variables and trade-offs/synergies have different effects on the changes in ESs, and their interactions can enhance the determinative power of the corresponding individual variable. The land use intensity is an extremely important factor affecting the trade-offs/synergies between the three services, indicating that rational land use planning in Beijing’s ECRL area is crucial for avoiding the negative impacts of trade-offs and enabling coordinated optimization of ESs. After the elimination of the cross-influence of environmental variables, the trade-offs/synergies change significantly, and the impact of environmental variables on ESs is compared with the net trade-offs/synergies. Environmental variables are the driving forces of the spatiotemporal changes in soil conservation. Precipitation and carbon sequestration have similar effects on water yield. Spatiotemporal changes in carbon sequestration are closely related to the other two services, with smaller influences from environmental variables.
The Yellow River Basin (YRB) occupies an important position in China’s socioeconomic development and ecological conservation efforts. Understanding the spatiotemporal characteristics of the relationships among multiple ecosystem services (ESs) and their drivers is crucial for regional sustainable development and human-earth system coordination. This study simulated food production (FP), water yield (WY), net primary production (NPP), soil conservation (SC), and habitat quality (HQ) in the YRB from 2000 to 2020, and evaluated the spatial evolution and the relationship of ESs at the raster scale. Redundancy analysis was used to identify the impact of natural, socioeconomic, and landscape patterns on the relationship between ESs. The results demonstrated that the average HQ per unit area decreased by 18.10%, while SC, NPP, WY, and FP increased by 42.68%, 47.63%, 30.82%, and 67.10%, respectively, from 2000 to 2020. The relationship between ESs in the YRB was dominated by weak trade-offs and weak synergies at a temporal scale, with the trade-offs strengthened in the Upper Yellow River Basin (UYRB) and the Middle Yellow River Basin (MYRB), and synergies strengthened in the Lower Yellow River Basin (LYRB). At the spatial scale, the relationships between HQ and WY, HQ and SC, HQ and NPP, FP and SC, and FP and HQ were all dominated by trade-offs, while other ES pairs were mostly based on synergistic relationships. In the YRB, the relationships among ESs were mainly influenced by human disturbance, precipitation, and land-use and exploitation intensity. Specifically, the trade-offs among ESs in the UYRB were primarily affected by precipitation, and those in the MYRB and LYRB by human disturbance. The heterogeneity of the landscape could also effectively promote synergies among ESs. This study could provide insights into trade-offs and synergies among ESs and their driving forces and lay a foundation for ecological restoration and sustainable development of ESs in the YRB.
Wetland vegetation is intimately related to floodplain inundations, which can be seriously affected by dam operation. Poyang Lake is the largest floodplain wetland in China and naturally connected with the Yangtze River and the Three Gorges Dam (TGD) upstream. To understand the potential impacts of TGD on Poyang Lake wetlands, we collected remote sensing imagery acquired during dry season from 1987 to 2020 and extracted vegetation coverage data in the Ganjiang Northern-branch Delta (GND) and the Ganjiang Southern-branch Delta (GSD), using the Object-oriented Artificial Neural Network Regression. Principal components analysis, correlation analysis, and the random forest model were used to explore the interactions between vegetation extent in the two deltas and 33 hydrological variables regarding magnitude, duration, timing, and variation. The implementation of the TGD advanced and extended the low-flow periods in Poyang Lake. Vegetation coverage in the GND and GSD increased at the rates of 0.39 and 0.22 km2/year, respectively. The reservoir storage at the end of September accelerated the runoff recession in the GND and the GSD, making low-flow events more influential for vegetation dynamics and shortening the response time of vegetation to the water regime. This study provides an important reference for evaluating the impacts of dam engineering on downstream wetlands.
