Yongchun Yang

Increasing external shocks have made the structural stability and vulnerability of the global corn trade network (GCTN) increasingly prominent. Based on country-level bilateral corn trade data, this study constructs a directed and weighted GCTN for each of 2004, 2014, and 2024. By integrating complex network indicators with a non-persistent attack simulation method, this study systematically examines the structural evolution and vulnerability changes in the GCTN at both the network and node levels. The results show that the GCTN has continuously expanded and is undergoing a structural transition from a random-like network toward a scale-free network. The United States has consistently remained the dominant supply center, while the export capacities of Ukraine and Brazil have increased substantially. Japan, South Korea, and Mexico have remained major demand centers, whereas China has shifted from a major exporter to a major importer. The regionalization of the strongest-link network has continued to strengthen. In 2024, the network exhibited higher clustering, greater path diversity, and improved transmission efficiency. Even after the failure of a relatively high proportion of nodes, the remaining network was still able to maintain or even improve its functions, indicating enhanced structural redundancy and stronger short-term resistance to local node disruptions. Although the number of vulnerable countries has declined, 13 countries remain persistently vulnerable. These findings provide empirical evidence for improving agricultural trade resilience and food security governance.

National economic security is essential for a nation's survival and development. The accelerating evolution of deglobalization imposes new demands on research in this area. This paper systematically reviews the evolution of research hotspots, research trajectories, and research frameworks in the field of national economic security, both domestically and internationally, using a combination of qualitative and quantitative methods based on the CNKI and WOS databases, and puts forward future prospects. Research since 1990 can be divided into three stages. The research hotspots at different stages and in different countries show national and stage differences, but are closely linked to economic globalization, national games, and emergencies. Based on the "pressure-state-response" framework, this paper summarizes the main lines, basic logic, and evolutionary paths of national economic security research under the interaction of threats and security. The collaborative evolution of threat and security sub-fields achieves horizontal expansion and presents national and stage differences. In security assessment, differing perceptions and perspectives on national economic security lead scholars to vary in their selection of assessment methodologies, indicators, and the construction of indicator systems. Synthesizing existing literature, this paper summarizes the "3+5" security guarantee system framework of security guarantee measures, points out the national and stage differences in guarantee measures, and generates "spillover" effects. Finally, based on the linkage of multiple risks, the game of multiple subjects, the interdisciplinary research framework, and the construction of national economic security theory, future prospects are put forward.

Promoting the development of low-carbon renewable energy is crucial for meeting the growing energy demand, reducing dependence on fossil fuels, and controlling carbon dioxide emissions. Clarifying the spatiotemporal characteristics of regional renewable energy production and its influencing factors will help optimize the spatial layout of renewable energy production and provide a solid theoretical basis for coordinating the development of all aspects of renewable energy production. Using panel data from 22 districts and counties in Ningxia from 2014 to 2021, this study employed the spatial Gini coefficient, Moran’s I index, standard deviational ellipse, and geographical detector to analyze the spatiotemporal evolution patterns and influencing factors of renewable energy production development in Ningxia. The results indicate that renewable energy production in Ningxia exhibits significant spatial agglomeration and autocorrelation. Temporally, renewable energy production shows a spatial expansion trend characterized by dynamic agglomeration patterns. The coupling degree between renewable energy generation and the spatial distribution of power production is relatively high, with notable regional disparities. Urbanization level, urban population, per capita GDP, and industrial SO₂ emissions have a positive impact on renewable energy production, while energy intensity and environmental regulation show insignificant effects. To further promote the development of renewable energy, Ningxia should strengthen power infrastructure construction at the county level, enhance the radiating and driving effects of high-value areas on surrounding cities and counties, optimize the spatial layout of power facilities based on the agglomeration trajectories of renewable energy production, integrate multiple types of renewable energy to improve overall generation efficiency and system stability, and encourage local enterprises to increase technological and economic investments in renewable energy, thereby advancing sustainable energy transition and achieving high-quality development in resource-based regions.

As an ecologically fragile and agriculture-dominated region in China, the Tibetan area is in urgent need of green transformation. Based on the survey data of 59 farmers in 16 villages in Hezuo City, this paper empirically examines the influencing factors and decision-making logic of the green production behaviors of farmers in Hezuo City using the Double Hurdle model and the moderated model, and the results show the following: (1) Cognitive norms and environmental regulations are the key elements determining the green production intentions and behavioral responses of farmers, and the driving effect of cognitive norms on behavioral response shows a declining trend in comparison with behavioral intention. Compared with behavioral intention, the effect of cognitive norms on behavioral response showed a downward trend. (2) The consistency between group social cognition and green production cognition significantly influences the behavioral intentions and behavioral responses of farmers regarding green production in Hezuo City. This is conducive to promoting farmers’ intentions to engage in and their continuous response to green production. (3) The role of environmental regulation in enhancing green production intention and behavioral response is more consistent and significant. However, it cannot continuously promote a green production response by influencing green production intention again. The green development strategy can help to align farmers’ cognitive and behavioral responses to green production. It is recommended that the government use environmental regulation as the primary means of driving the current green transformation in Tibetan areas.

网络分析应用日益广泛，但其内在研究也逐渐因数据获取、复杂性和多元性等显露瓶颈。论文回顾了网络思维和网络分析方法，提出了网络研究可能存在的边界，系统梳理和解构了地理学网络研究的发展历程和不同层次，分析了其研究趋势和研究突破，并指出了关键问题与未来探索方向。研究显示：网络分析既是一种强调抽象思维、系统思维与关系思维的科学思维方式，也是一种分析复杂系统结构的科学方法；网络研究具有一定的边界。网络分析自20世纪60年代引入地理学，已发展出理论—对象—方法3个层次，在地理学知识生产中扮演差异化角色，并形成了以非社会节点之间的非社会联系为主的研究趋势；在认知与思维、科学理论与机理分析、方法与数据、现实视角与意义等4个方面取得突破。地理学网络研究面临网络思维和理论化模型运用与构建不充分、机制分析不足、数据收集困难与表达不充分、网络测度视角单一与方法技术落后等4个关键问题；未来可在综合性的地理学网络理论构建与整合、适合地理学网络分析的新方法研究、增强地理学网络研究数据的获取路径、地理学网络研究测度视角的改进、成果应用与实践方法的提升等5个方面探索地理学网络研究发展路径。

Scientifically identifying the impact of urban development levels on the ecological environment in China’s grassland regions from a classification perspective is crucial for stabilizing grassland ecosystems and optimizing urban development in grassland cities. Using the Inner Mongolia Autonomous Region as a case study, this research constructs a conceptual analysis framework for the coordinated state between the urban development level and the ecological environment in China’s grassland regions based on the theory of dual economic structures. Employing the Granger causality test, nonlinear fitting, and coupling coordination degree model methods, the heterogeneity and coordination between urban development levels and ecological environment in China’s grassland areas from 2000 to 2020 are comprehensively analyzed. The findings reveal the following: (1) Capital-type central cities and growing resource-based cities, with high levels of development, positively nurture the grassland ecology, exhibit high labor mobility, and experience low endogenous and exogenous pressures, resulting in high coordination. (2) Pure agro-pastoral cities, with low development levels, negatively impact the grassland ecology, have low labor mobility, and face high endogenous and exogenous pressures, resulting in low coordination. (3) Regional central cities, with moderate development levels, exert a neutral counterbalance effect on the grassland ecology, with opposing endogenous and exogenous pressures, leading to moderate coordination. (4) When the impact relationship ranges from “positive-neutral-negative,” the endogenous and exogenous pressures on the grassland ecology by declining resource-based cities and developing agro-pastoral cities are determined by their specific development levels, showing variations from “large → balance → small” to “small → balance → large,” with coordination fluctuating between “high-moderate-low”. (5) Special ecological cities are less affected by urban development levels, with coordination levels determined by the ecological foundation. Analyzing the heterogeneous coordination between urban development levels and the ecological environment for different types of cities in grassland regions is significant for improving the overall quality of the grassland ecological environment and exploring distinctive urban development models.

This article examines the urban development strategies and pro-growth politics in China from a local state leadership perspective, focusing on the power dynamics within the local state leadership under China’s fragmented authoritarian system. The state-leading group is an innovative governance technique intentionally designed to overcome the institutional flaws of ‘ tiao-kuai segmentation’. It plays a critical role in fostering a common vision of ‘growth promotion’, aligning goals and unifying actions in the administrative system, broadening social consensus and promoting public–private partnerships. This study improves upon the understanding of the micro-mechanisms of state-led urban development within China’s fragmented authoritarian regime by exploring the heterogeneity of state actors as well as the agency of key local political actors (groups) in aligning goals and interests within and beyond the state and their political rationalities. By highlighting the conflicts and negotiations that exist within the state, the debate on state-led urban development and pro-growth politics is extended using China as an example.