Since the advent of the “Anthropocene”, the multifaceted interactions and impacts of global climate change, intensive human activities, and information intelligence have intensified. The global human-earth system and its spatial patterns are undergoing significant challenges in relational restructuring and functional reconstruction, while modern geographical research faces an urgent need for theoretical innovation and paradigm transformation. This paper focuses on establishing the “Four-Dimensional Integration Model of Geographical Science-Technology-Engineering-Practice” (referred to as the Geo-STEP model), systematically elaborating its theoretical connotations, four-dimensional interaction mechanisms, and innovative applications. The study demonstrates that the Geo-STEP model is a systematic, comprehensive, and interconnected modern geographical methodology system, which emphasizes multidimensional interconnections, multi-system coupling, and multi-scenario coordination, forming an organic whole with multiple couplings of geographical science, technology, engineering, and practice. Its transmission logic generally follows the universal paradigm of “scientific cognition (S)-technological innovation (T)-engineering implementation (E)-practical feedback (P)”. Geographical science (S) is the theoretical foundation of the Geo-STEP model, geographical technology (T) is the innovation engine of the Geo-STEP model, geographical engineering (E) is the implementation carrier of the Geo-STEP model, geographical practice (P) is the value embodiment of the Geo-STEP model, and the 4 dimensions of the Geo-STEP model (S-T-E-P) form a complete knowledge action loop. In the experiment of the National Academy of Rural Revitalization (Lankao) and its “Geographical Engineering Academy”, the author achieved the integrated development of Geo-STEP through the innovative “three in one linkage” model of combining science and engineering, integrating science and education, and combining school and local areas, and achieved significant results in serving the national rural revitalization strategy and promoting the interdisciplinary integration of geographical science and engineering. The paper analyzes the application scenarios of the Geo-STEP model in key areas such as territorial spatial planning, the Yellow River Basin strategy, rural revitalization strategy, and geographical education, preliminarily validating its unique advantages and comprehensive capabilities in analyzing and addressing complex human-earth interaction issues. It provides theoretical references and practical paradigms for the optimization and reconstruction of the geographical science system and disciplinary system under the spatiotemporal patterns of the “Anthropocene” and the “Human-Earth Sphere”.
The integration of culture and tourism is a key component of Chinese-style modernization. In the digital era, online flow has surpassed traditional resource endowments and become a core driver of local development and culture-tourism integration. Through platformization and algorithmization, flow reshapes tourism space and generates a flow “carnival” dominated by algorithms and mass participation. However, the irrational pursuit of flow by small and medium-sized cities has led to a “frenzy” state, exposing tensions between flow logic and the sustainable development of local tourism. Existing studies have discussed the emergence and diffusion of influencer-driven tourism, yet they lack in-depth analysis of the paradoxes behind flow and their local embeddedness. Based on the theory of spatial production, this paper systematically examines the internal relations among flow, locality and tourism in the digital era. It analyzes the action logics of governments, platforms, tourists, and residents within flow networks, and explains how flow, as a factor of spatial production, restructures tourism geographical space. The study compares internet-famous officials and grassroots influencers in terms of their popularity paths, resource sources and action logics, finds that both face challenges in converting flow into long-term development momentum. It identifies 4 core paradoxes of digital-era tourism: distortion of tourism essence, silencing of local characteristics, misplacement of institutional support, and imbalance in flow adaptation. And it analyzes their manifestations and formation mechanisms. The findings reveal that the alienation from flow “carnival” to “frenzy” reflects an imbalance between digital capital and administrative power in spatial production. Selective flow allocation by platforms and performance evaluation pressure on local governments jointly drive irrational competition for flow, and the 4 paradoxes stem from a fundamental mismatch between flow logic and local development logic. The study argues that flow itself is not the root cause of tourism problems, and that resolving digital-era tourism paradoxes requires the realization of “flow justice”, which ensures fair rights for different regions and diverse actors in flow generation, allocation, conversion, and benefit sharing. Achieving flow justice requires a collaborative governance system involving government, platforms, and the public. Governments should shift from chasing flow to improving infrastructure and public services, platforms should optimize algorithm rules to balance fairness and efficiency, and the public should participate in governance through institutionalized channels. Only by closely coupling human emotional experience, local resource endowments, and external support, can short-term flow be transformed into endogenous drivers of local culture and tourism development. The issue of flow justice will become a frontier topic across geography, tourism studies, and related disciplines.
The transformation and development of rural areas serve as a significant driving force for rural modernization. Quantitatively exploring the impact of the transformation on modernization level (ML) is crucial for advancing rural transformation and enhancing the modernization level. Based on field survey data from 1 155 specialized villages (SV) in Henan Province between 2008 and 2017, this study analyzed the spatio-temporal evolution and spatial agglomeration characteristics of the transformation and development level (TDL) and ML. A spatial econometric model was employed to explore the degree of influence of the TDL on ML and the spatial spillover effect. The study findings are as follows: 1) From 2008 to 2017, the TDL in Henan Province’s SVs showed an increasing trend, but the coefficient of variation rose from 0.214 in 2008 to 0.307 in 2017, indicating growing polarization. The TDL was predominantly low to medium, with a generally low development level, exhibiting a north-high, south-low distribution pattern. Spatial agglomeration was significant, although the degree of agglomeration gradually decreased, with the high-density core area evolving from a ‘point core’ to a ‘face-like’ distribution. 2) The ML of SVs followed a similar trend to the TDL, with relatively smaller spatial differences, primarily low to medium grades, and a north-high, south-low spatial pattern. The agglomeration was notable and spread from the northern and central regions to the rest of the province, although the degree of agglomeration gradually weakened. Notably, the agglomeration level around Jiaozuo, Zhengzhou, and Xinxiang in the north increased and spread to multiple areas. 3) The TDL of SVs had a significant positive impact on the ML. Additionally, there was a clear spatial spillover effect observed in both 2008 and 2017, with each 1% increase in the TDL of SVs contributing to increases of 0.251% and 0.121% in the ML of neighboring areas, respectively. 4) On the foundation of economic development, factors such as transportation level, industrial upgrading, developmental vitality, topography, and geographical location directly propel the TDL of SVs while indirectly driving the improvement of ML, ultimately shaping the spatial pattern of ML in SVs.
Promoting the development of specialized and advantageous industries constitutes a crucial initiative for advancing rural industrial prosperity and comprehensive revitalization. As a fundamental spatial unit, villages play a key role in the development of rural specialized industries. Understanding the evolutionary mechanisms driving specialized villages’ transformation proves essential to operationalize rural revitalization and build a strong agriculture. This need is heightened by global supply chain restructuring and intensifying climate change, as well as domestic challenges such as fragmented industrial distribution, resource bottlenecks, and low production efficiency. Extant studies have extensively examined the processes, mechanisms, and impacts of specialized village transformation across multiple spatiotemporal scales. Process studies characterize industrial operations through production system perspective. Mechanism analyses pinpoint drivers spanning entrepreneurial, geographic, institutional, and resource dimensions, supported by specialization theory. Impact evaluation prioritized income effects on rural households, with spatial analyses revealing cluster expansion, knowledge diffusion, and eco-production spillovers. While existing studies have identified key aspects of specialized village transformation, critical gaps persist in integrated theoretical frameworks, and the regional variations and sustainability of these transformation models remain to be explored in depth. To address these gaps, future studies should integrate multidisciplinary perspectives to develop a comprehensive analytical framework. This involves: 1) Analyzing transformation processes through multiscale resource linkages, multi-stakeholder interactions, and multidimensional factor restructuring; 2) Investigating transformation mechanisms via factor interdependencies and driver cascades; 3) Assessing transformation effects through integrated metrics across social-ecological dimensions and spatial scales. Such advancements will ultimately generate novel perspectives of rural transformation, provide actionable insights for place-based strategies to cultivate specialized industries and achieve rural revitalization comprehensively.
Traditional village is not only a vital part of cultural heritage but also a significant vehicle for rural economic development. Against the backdrop of urban-rural integration, this study selects 3 tourism-driven traditional villages as the research subjects, and employs a combination of quantitative measurement and qualitative analysis to explore the production logic of the “human-place-industry” synergy in traditional villages. The study found that: 1) The livelihood transformation of the production subjects serves as the driving mechanism for the “human-land-industry” synergy. The livelihood transformation of traditional villages can be summarized as the resource reconstruction type from land dependence to capital drive, the cultural endogenous type from cultural accumulation to market empowerment, and the policy synergistic type from policy guidance to multi-dimensional linkage; 2) The factor reconstruction of the production carrier is the characterization schema of “human-land-industry” synergy. The production process will be reflected in the spatial form, deconstructing the traditional village schematic language system, using the schematic context to lay down the logic of spatial formation, schematic grammar to explore the order of spatial organization, and the schematic vocabulary to reshape the spatial combination of symbols. 3) The integration of industrial formats in the production system constitutes a symbiotic pathway of “human-land-industry” synergy. Utilizing the “human” subject consciousness and integrating the “land” resource elements, and the production of the “industry” reacts on the “human” production. At the same time, the production of “industry” reacts to the “human” production body and “land” production carrier, constituting a virtuous cycle of “human-land-industry” system synergy.
Strengthening specialized industry holds significant importance for advancing rural industrial revitalization and promoting integrated urban-rural development. Building upon actor-network theory, this article constructs an actor-network analysis framework for the transformation of specialized planting industry, exploring the process and mechanisms of mango industry transformation in Tiandong County, Guangxi, under government leadership. The study reveals: 1) The transformation of Tiandong County’s mango industry progressed through distinct phases: exploratory inception, gradual development, rapid expansion, and steady progression. This complex process involved the construction of an actor network under local government leadership. By focusing on key issues and coordinating interests, the local government integrated administrative, scientific research, market, and social resources. These combined inputs propelled the mango industry’s shift from fragmented, extensive operations toward scaled, specialized, standardized, branded, industrialized, and clustered production. 2) Throughout this process, intricate network relationships emerged among heterogeneous actors. Local government remained the core actor, research institutes provided sustained technological support, market capital and public participation became increasingly diverse, and the role of non-human actors grew increasingly prominent. 3) The key to advancing the transformation of county-level specialized planting industry lies in leveraging resource and environmental suitability. Through stakeholder collaboration and factor integration, it is essential to establish robust mechanisms for industrial co-cultivation, brand co-creation, benefit sharing, and value co-creation among diverse actors.
Rural areas in environmentally sensitive zones face the contradiction between ecological conservation and industrial growth, making industrial transformation an inevitable pathway for development. However, few studies have empirically examined whether such transformation can truly be achieved in these unique rural contexts through real-world case analyses. This article takes Shuangwan Village in Suzhou City as a typical case study, constructing a theoretical framework for rural industrial transformation from the perspective of actor-network theory (ANT). Through field investigations and hybrid coding methods, the processes and mechanisms of Shuangwan Village’s industrial transformation are explored. The findings reveal: 1) Shuangwan Village underwent 3 phases of industrial transformation—industrialization, agricultural specialization, and agriculture-tourism integration—with varying degrees of participation and heterogeneous roles played by 3 categories of actors: natural environments, institutional conditions, and social agents. The industrialization phase failed due to ecological degradation and regulatory dissent, yet the preserved ecological foundation created opportunities for subsequent transformations. The innovative visions of rural elites and the practical feedback from villagers emerged as critical to successful transitions. 2) Non-human actors, such as the natural environment and environmental regulations, participated in the rural industrial transformation in environmentally sensitive areas to varying degrees, exerting heterogeneous effects through different translation processes. Villages in environmentally sensitive areas possess the potential for industrial transformation like other villages; however, due to the complex interplay of internal and external factors, such transformations face greater difficulty and higher costs. 3) Key actors consolidated industrial alliances by negotiating interests, mediating conflicts, mobilizing intermediary organizations, and reinforcing their discursive power, thereby strengthening inter-actor linkages. This study clarifies the processes of multi-actor participation in industrial transformation within environmentally sensitive rural areas, as well as the mechanisms of power dynamics and discursive construction among stakeholders. Furthermore, through a diachronic study, this paper elucidates the agency of non-human actors in rural industries and the generative process of rural industrial subjects. It provides practical insights for achieving sustainable industrial transformation in similar regions.
Based on the 6 batches of specialized, refined, differential, and innovative (SRDI) “little giant” enterprises recognized by the ministry of industry and information technology between 2019 and 2024, this study categorizes them into 4 functional segments: corporate headquarters, research and development, manufacturing, and operational services. By applying a headquarters-branch structure assignment model and the self-organizing feature map (SOFM) model, the study investigates the spatial patterns of functional specialization among Chinese cities. Additionally, it employs negative binomial regression as well as ordinal and multinomial logistic regression models to identify influencing factors. The findings indicate that: 1) Functional specialization in Chinese cities exhibits marked spatial concentration and differentiation. Eastern coastal cities such as Beijing, Shanghai, and Shenzhen dominate the layout of high-end functions, while central and western cities primarily undertake manufacturing roles. For most cities, the level of functional specialization generally aligns with their administrative hierarchy; however, in some traditional core cities like Kunming and Lanzhou, mismatches between hierarchy and specialization are observed. 2) The functional specialization system can be classified into 3 tiers: Functionally diversified, functionally balanced, and manufacturing-dominated cities. These types do not demonstrate significant regional clustering. 3) Over time, cities led by high-end functions—such as Hangzhou and Wuhan—have experienced increasing functional diversification, while small and medium-sized cities are becoming more specialized in manufacturing. Overall, this reflects a trend of intensified functional solidification and growing polarization. 4) Factors such as technological support, business environment, consumption level, and transportation accessibility significantly promote the deepening of functional specialization in Chinese cities. In contrast, the level of economic development and degree of openness exert suppressive effects on operational services and manufacturing functions, respectively.
This study focuses on the spatial data of commercial bank branches in China. Using hot spot analysis and geographical detector methods, we investigate the spatial distribution characteristics of more than 220 thousand commercial bank branches and different types of commercial banks in China, and then explore the driving factors affecting spatial distribution. The main findings are as follows: 1) From a national perspective, there is a significant disparity in the distribution of commercial banks across China on either side of the “Hu Huanyong Line”, presenting a spatial pattern of “more in the east and fewer in the west”. Different types of commercial banks exhibit different agglomeration patterns. 2) The hotspots of commercial banks are mainly clustered within urban agglomerations in the eastern and central regions. Joint-stock commercial banks and city commercial banks are highly clustered in urban agglomerations or metropolitan areas, presenting a multi-cluster distribution pattern, while rural financial institutions show a planar distribution pattern connecting multiple urban agglomerations. 3) Results from the geographical detector analysis show that economic, social, technological, and governmental factors significantly influence the spatial distribution of commercial banks in China, among which population size, economic development, financial development, technological innovation, and administrative level are the main influencing factors. 4) Results of the interaction detector analysis show technological factors together with population size enhance the spatial agglomeration of both state-owned and non-state-owned commercial banks by facilitating market information flow and clustering of innovation elements. Moreover, the level of regional financial development, driven by the level of technological innovation, can strengthen the spatial gravity to different types of non-state-owned commercial banks. In addition, banks with larger service coverage have higher demand for economic conditions, and the effect of the growth rate of the secondary industry development level is significant. In addition, the differences in the regional nature of service areas will cause differences in the two types of factors dominated by different types of commercial banks. Finally, based on the analysis results, suggestions are put forward, including developing new exclusive services of commercial banks, accelerating the cultivation of financial talents, and increasing the degree of opening up of the financial industry.
Since the establishment of diplomatic relations between China and South Korea, geopolitics has driven the rapid development of South Korean-invested enterprises in China. However, geopolitical events such as the deployment of the THAAD system in South Korea and the China-U.S. trade frictions have reshaped the bilateral economic order and supply chain structure. There is an urgent need to clarify the territorialization dynamics, i.e., the entry and exit strategies, of South Korean-invested enterprises in China. This article, employing research methods of in-depth interviews, participatory observation, and text analysis, explores the changes in the production networks of South Korean-invested enterprises in Dongguan from a territorial perspective. The findings are as follows: 1) Geopolitical crises have a profound impact on the resource integration of South Korean-invested enterprises’ production networks, manifested specifically in the strategies of foreign enterprise entry and exit. 2) In the face of geopolitical tensions, under the guidance of administrative and market entities, South Korean-invested enterprises adjust their territorialization strategies and relocate to circumvent local and trade barrier regulations. 3) The reorganization and re-territorialization of South Korean-invested enterprises’ social networks are actually the results of multi-actor negotiation and benefit maximization. Specifically, the study reveals how firms navigate uncertainty through spatial fixes such as cross-border production fragmentation and supply chain diversification, while also leveraging localized networks and government-business collaborations to embeddedness. The development trajectory of South Korean-invested enterprises in Dongguan demonstrates the complexity and dynamism of transnational capital activities in the context of globalization. This study transcends the limitations of previous studies that primarily relied on macro data such as trade flows to explore the evolution of economic cooperation and competition between countries. Instead, the study adopts a micro-level approach. By analyzing the behavioral changes in the business strategies of foreign-invested enterprises, it reveals how power relations among different actors infiltrate the interactive process of economic production. The research contributes to the understanding of firm-level agency in geopolitical restructuring and offers insights for policy-making aimed at stabilizing foreign investment under turbulent external conditions.
The development of the sports footwear and apparel industry in Quanzhou is regarded as a typical example of the “Jinjiang Model”, which demonstrates a distinctive path that integrates regional branding, industrial clustering, and multi-regional strategies. Based on enterprise equity relationship data, and combining quantitative analysis with in-depth interviews, this study constructs a “region-enterprise-institution” analytical framework to systematically identify the spatial expansion trajectories and driving mechanisms of Quanzhou’s footwear and apparel enterprises across national, provincial, and municipal scales. The findings reveal that: 1) In the process of brand upgrading, the industry faces regional lock-in problems arising from rising factor costs and limited development space, prompting enterprises to break through spatial constraints through multi-regional strategies. 2) At the national scale, Quanzhou’s footwear and apparel enterprises show a stepwise shift from the eastern region toward the central and western regions; headquarters and R&D functions are concentrated in major eastern cities, while manufacturing expands into lower-cost inland areas. At the provincial and municipal scales, both proximity-based and leapfrogging expansion patterns coexist. 3) Multi-level government policies in investment promotion, industrial coordination, and factor provision work in synergy to facilitate the relocation of manufacturing functions and the concentration of high-end functions in core cities. 4) Enterprise expansion has further strengthened the control of Quanzhou’s leading brands over the industrial chain and enhanced their regional competitive advantages. Building on firm-led spatial expansion strategies, this paper advances the theoretical application of regional lock-in and de- and re-territorialization in industrial geography. Rather than treating firms as passive responders to cost pressures, it conceptualizes them as strategic actors that actively reconfigure spatial trajectories through multi-regional embeddedness. This process reflects a hybrid spatial logic in which inherited locational constraints are loosened while headquarters control is reinforced, thereby contributing to regional economic restructuring in the context of China’s manufacturing transformation.
Focusing on rural migrant families returning to county towns in Yangzhou, Jiangsu Province through the lens of translocal theory, this study provides the following conclusions: 1) Spatial restructuring of family residency. Return migration has reshaped household spatial patterns into 3 translocal configurations: county co-residential families (shared residence in county towns), cross-county multi-local families (members dispersed across multiple counties), and urban-rural dual-location families (split between cities and villages). Among these, county co-residential and urban-rural families demonstrated strengthened emotional bonds and local belonging, accompanied by egalitarian family roles and diversified occupational identities. In contrast, cross-county multi-local families exhibited emotional estrangement, simplified family hierarchies (e.g., rigid gender roles), and occupational gender biases favoring male dominance. 2) Reconfiguration of social networks. Returnees actively reconnected with local kinship and occupational networks while sustaining translocal ties to their original migration destinations. This dual embeddedness fostered a hybrid subjectivity, blending localized social capital with cross-regional connectivity, thereby redefining their agency in both spatial and social dimensions. 3) Divergent impacts on livelihood resilience. For urban-rural and intra-urban translocal families, livelihood resilience improved through two pathways: externally, by accumulating and leveraging cross-local economic and social resources (e.g., urban savings and rural land rights), and internally, through collaborative and equitable household decision-making. However, cross-county multi-local families experienced stagnant resilience due to fragmented resource integration (e.g., limited access to localized welfare) and persistent intra-household inequalities in labor division and power dynamics. These findings highlight the nuanced interplay between return migration, family adaptability, and translocal practices, calling for differentiated policy interventions to support diverse family structures in China’s urbanization process.
Chinese modernization is modernization that achieves common prosperity for all, and rural migrant workers’ urban integration is a key step in promoting common prosperity for all. This study adopts a qualitative research method, exploring the spatial practice and underlying mechanisms of rural migrant workers’ urban integration in Nanjing from an interactive theoretical perspective of life course and the practice everyday life. The findings are as follows: 1) The process of rural migrant workers’ urban integration can be divided into three phases: the survival and embeddedness phase, the settlement negotiation phase, and the psychological integration phase; 2) There are agential differences and path divergence in their integration. During the survival and embeddedness phase, they develop adaptive strategies through engagement in the secondary labor market and transitional residence. During the settlement negotiation phase, a divergence emerges between upward and downward occupational mobility. During the psychological integration, constrained by unequal access to social security, a cognitive dissonance characterized by “emotional belonging-identity alienation” manifests; 3) Structured tensions, agency, and the dynamic adaptation of social networks collectively shape rural migrant workers’ spatial practice and differentiated integration trajectories. This study introduces the theory of everyday life practices, which enriches the analysis of agency within the “structure-agency” framework of life course theory and provides valuable insights for the government to formulate targeted integration policies.
Based on population census data and prefecture-level statistical yearbook data from 2000 to 2020, this study employs spatial analysis methods to investigate the spatio-temporal evolution patterns and formation mechanisms of elderly empty-nest households in northeast China over the past two decades. The main findings can be summarized as follows. 1) Compared with the national average, the northeast China exhibits a more severe degree of population ageing and a more pronounced trend toward empty-nest living among older adults. Both the ageing level and the extent of empty-nest households are consistently higher than the national average level throughout the study period. Although couple-only empty-nest households remain the dominant form, the proportion of elderly individuals living alone has increased at a significantly faster rate, indicating a rapid deepening of solitary empty-nest conditions and a growing vulnerability among the elderly population. 2) The spatial differentiation of elderly empty-nest households in northeast China is highly significant. Urban areas consistently display higher empty-nest rates than rural areas, reflecting long-term differences in family structure, migration patterns, and social support systems. Spatially, a semi-ring distribution pattern has gradually emerged, characterized by lower empty-nest rates in the central areas of the three provinces and higher rates in the border regions of Heilongjiang Province and Jilin Province as well as in central Liaoning Province. Resource-based cities show particularly high levels of solitary empty-nest households, which can be attributed to sustained labor out-migration, industrial transformation, and long-term population shrinkage. 3) From the perspective of formation mechanisms, the evolution of elderly empty-nest households in northeast China is jointly shaped by demographic, socio-economic, and cultural institutional factors. Persistent population outflows, rapid urbanization, and a cultural shift toward smaller family norms have consistently acted as key driving forces behind the intensification of empty-nest phenomena. Further analysis reveals that the spatial differentiation of solitary empty-nest households is influenced by the combined effects of all 3 dimensions, whereas the spatial variation of couple-only empty-nest households is primarily driven by demographic and cultural institutional factors, showing relatively low sensitivity to socio-economic conditions.
To address the challenge of accurately characterizing soil nitrogen spatial variation and quantifying its causes in the context of irrigated farmland fragmentation in plateau lake watersheds, this study constructed a high-resolution mapping and driving relationship analysis framework for soil total nitrogen (STN) driven by multi-source geoscience data. It achieves fine spatial prediction of STN content through an ensemble learning tree model and quantifies the nonlinear response and threshold effect of STN content to key driving factors based on a generalized additive model (GAM). Taking the Qilu Lake irrigation area in Yunnan Province as the study area, the high frequency and intensity of agricultural cultivation in this region exacerbates the heterogeneity of the soil environment. The study results based on 216 surface soil samples indicated that the XGBoost model performed better in STN mapping (RMSE=0.85 g/kg, R2=0.53, CCC=0.72). Compared with the RF model, RMSE decreased by 7.6%, and R2 and CCC increased by 20.45% and 30.91% respectively, showing stronger predictive ability in heterogeneous plateau irrigation areas. Based on Local Indicators of Spatial Association (LISA), STN was identified to have significant spatial clustering and heterogeneity features, and the clustering pattern distribution was consistent at both the original sample point and spatial continuous mapping levels, verifying the rationality of the mapping results from the perspective of spatial pattern. STN is nonlinearly regulated by factors such as soil moisture content (SMC), elevation (Elev), vegetation index, and brightness, and has obvious thresholds (e.g., SMC: 48.51%, Elev: 1 808 m). It has a linear relationship with distance from roads and spread index, reflecting the more direct and continuous impact of human activities on STN content. The findings can provide technical support and scientific decision-making for soil nitrogen monitoring, agricultural management, and ecological protection in irrigation areas of plateau lake basins.
The Wuding River is one of the primary sediment contributors to the Yellow River system, but its century-scale sediment transport patterns remain quantitatively underexplored. To extend research on long-term sediment transport in its tributaries, the evolutionary process of the annual sediment transport and its influencing factors were explored through multi-source data collection, recent archival analysis, statistical analysis, wavelet analysis, double mass curve analysis, and comparative analysis in the Wuding River during 1935—2020. Recent archival and statistical analyses conducted at the Baijiachuan hydrological station on the Wuding River reveal that the period from 1935 to 1971 experienced 19 years of elevated sediment discharge, representing 51.4% of the total duration. In contrast, the interval from 1972 to 2020 recorded 14 years of high values, comprising 28.6% of the overall timeframe, attributed to a significant alteration in sediment transport in 1971. Then, wavelet analysis reveals that only 2 muti-types of time-scale features exist without the influence of the abrupt change of sediment transport in 1935—2020, and the main periods are 2.7 a, 25.0 a, 3.8 a of 1935—1971, 5.7 a, 20.0 a, 8.0 a of 1972—2020. The result reflects short periods that become long in time-scale features after the abrupt change and also demonstrates the complexity of the evolution of sediment transport in the Wuding River. Finally, quantitative assessment using double mass curve analysis and comparative analysis indicates that human activities contributed 61.3% to sediment reduction, substantially outweighing the 38.7% contribution from natural factors from 1972 to 2020. Specifically, soil and water conservation measures such as extensive construction of reservoirs—silt dams, and terraces were the direct reasons for the abrupt change in sediment transport in the 1960s, and the main reason for the decrease in sediment transport was that the ‘Grain for Green Project’ has launched at the end of the 20th century. Nevertheless, human interventions have also unexpectedly created a new set of economic and environmental issues. Therefore, to realize the strategy of ecological protection and high-quality development of the Yellow River Basin, the approach to soil erosion management in the Loess Plateau needs to shift to the overall coordination of the whole basin and to set up a certain elasticity and change space, to maintain the dynamic balance between soil erosion management in the middle reaches and geographic stability in the lower reaches. The research provides long-term data references for the comprehensive management of small watersheds and the evaluation of soil and water conservation benefits on the Loess Plateau.
By collecting atmospheric precipitation, river water, groundwater, and snowmelt from the Kashi River Basin between September 2020 and September 2024, this study employs stable isotope techniques to analyze the variation characteristics of each water body. Using the MixSIAR model to quantify river water recharge sources, estimate temporal and spatial evaporation loss of river water based on evaporation enrichment model and isotopic mass balance model, and investigate their influencing factors. The results show that: 1) Precipitation hydrogen and oxygen stable isotope values in the Kashi River Basin are more enriched compared to river water, groundwater, and snowmelt water. Seasonal variations in precipitation hydrogen and oxygen stable isotopes show enrichment in summer, followed by spring and autumn, and depletion in winter. Seasonal variations in river water hydrogen and oxygen stable isotope values are not particularly pronounced, while spatial variations show enrichment at mid-elevations and depletion at high elevations. Groundwater exhibits similar hydrogen and oxygen stable isotope values to river water. Snowmelt water is depleted in hydrogen and oxygen stable isotopes relative to river water. 2) River water is primarily replenished by precipitation and groundwater. In April, precipitation and groundwater contributed 46.4% and 43.8% respectively, while snowmelt accounted for a smaller proportion. By July, snowmelt contribution increased to 23.6%, while the shares from precipitation and groundwater decreased. In September, precipitation contributed less to river water, with groundwater and snowmelt accounting for 56.6% and 25.8% of the supply, respectively. 3) The temporal variation in river evaporation loss shows the highest values during summer, with a maximum loss of 41%. Spring follows with a maximum loss of 25%, while autumn exhibits lower evaporation losses and winter shows no evaporation loss. Spatially, evaporation loss is greatest in mid-elevation areas. These findings hold significant implications for understanding local water cycles and their response to climate change in mountain ecosystems.
Abnormal climate change has led to frequent extreme hydrological events such as floods and droughts, and the characteristics of extreme flood changes in river basins have gradually become a research hotspot in recent years. Based on meteorological and hydrological station observations in the upper reaches of the Jinsha River Basin, Mann-Kendall trend analysis and cumulative anomaly method, we analyzed the characteristics and driving factors of extreme floods in spring and summer in the upper reaches of the Jinsha River during 1990—2022. The results show that there is a significant difference in the characteristics of spring and summer floods in the upper reaches of the Jinsha River Basin. Firstly, from the perspective of runoff, the average annual runoff in the upper reaches of the Jinsha River Basin showed an increasing trend, while the runoff in summer and spring showed a decreasing trend during 1990—2022. In the past 33 years, the runoff has undergone a transition from dry to abundant. Secondly, in terms of frequency, intensity and duration of floods, there have been 13 extreme spring flood events and 18 extreme summer flood events in the upper reaches of the Jinsha River Basin, with 4 each since 2015. The intensity of extreme flood events in spring shows an increasing trend, while in summer it shows a decreasing trend. The duration of spring floods shows a decreasing trend, while in summer floods it shows an increasing trend. The start dates of both spring and summer floods are either advanced or delayed. Furthermore, analyzing the driving factors of extreme floods from the perspectives of extreme climate and atmospheric circulation, we found that extreme runoff values are not only significantly affected by extreme precipitation, but also closely related to extreme minimum temperatures. The abnormal disturbance of westerly and monsoon circulation is the key to triggering extreme flood events in spring and summer. Therefore, in the context of climate change, understanding the characteristics and driving factors of extreme flood changes in the upper reaches of the Jinsha River Basin is crucial for downstream reservoir operation.
This study employs the Markov-PLUS model to simulate future land use scenarios, analyzing the ecosystem service value (ESV) and trade-off/synergy relationships under different development pathways in Dongting Lake Eco-economic Zone. Ecological functional zoning is delineated to provide a scientific basis for regional sustainable development. By simulating land use changes in Dongting Lake Eco-economic Zone under three scenarios for 2030—baseline (S1), ecological protection (S2), and economic priority (S3)—the ESV and trade-off/synergy relationships under each scenario are analyzed. A total of 653 townships are classified into four types of ecological functional zones, with corresponding management recommendations and countermeasures proposed. The results show that: 1) In 2030, the total ESV under S1, S2, and S3 scenarios are 366.475 billion yuan, 375.291 billion yuan, and 364.628 billion yuan, respectively. Only the S2 scenario shows an increase in ESV compared to 2020, significantly outperforming the other scenarios, confirming the effectiveness and scientific validity of the “ecological priority” policy. In all scenarios, the proportion of ESV contributed by water areas exceeds 55%, with hydrological regulation, climate regulation, and soil conservation ranking as the top three service types in terms of ESV contribution. 2) Ecosystem services generally exhibit synergistic effects across all scenarios, with high trade-off values mainly observed between food production and climate regulation, as well as soil conservation. These trade-off relationships are more pronounced under the S2 scenario. 3) Based on the identification of ecosystem service clusters, Dongting Lake Eco-economic Zone is divided into four functional zones: agricultural multifunctional production zone, ecological comprehensive protection zone, water resources habitat conservation zone, and urban ecological maintenance zone. Differentiated management measures proposed according to the dominant functions of each zone provide actionable solutions to the conflict between ecological protection and economic development in Dongting Lake Eco-economic Zone.
