Yellow River Basin Management Under Pressure: Present State, Restoration and Protection III: Lessons from a Special Issue

1. Introduction

This Special Issue is the third edition following the publication of the first issue of “Yellow River Basin Management under Pressure: Present State, Restoration and Protection” in 2022 and the second issue in 2023. Currently, issues such as the coordination of human–water relationships, water security, water resource allocation, ecological environment restoration, water pollutant treatment, and the coexistence of new pollutants continue to constrain the high-quality development of the Yellow River Basin. Thus, this Special Issue focuses on the current state, challenges, and solutions relating to Yellow River basin management and sustainable development under pressure, aiming to help improve ecological protection and achieve high-quality development. The topics included the following:

(1) The current status and constraining factors of the ecological environment and high-quality development in the Yellow River Basin;

(2) Opportunities and strategies for management;

(3) Harmonious regulation of human–water relationships;

(4) Emerging pollutants issues;

(5) The impact of environmental changes on water security and water resource allocation;

(6) Ecological restoration and protection.

This Special Issue has aroused widespread interest among scholars, with a total of 10 related academic papers published online recently.

2. Overview of This Special Issue

This Special Issue includes ten original contributions focused on Yellow River basin management under pressure. Considering the unique regional characteristics of the Yellow River in China, the contributions mainly result from research conducted by universities and R & D institutions in China. The ten articles in this Special Issue can be divided into five categories: category A: “Resource Endowment and Basic Characteristics”; category B: “Opportunities and Strategies for Management”; category C: “Harmonious Regulation of Human–water Relationships”; category D: “Environmental Pollution and Governance”; category E: “Ecological Restoration and Protection”.

In category A “Resource Endowment and Basic Characteristics”, Zhiqiang Zhang et al. (contribution 1) have analyzed the applicability of nine water indexes in the Yellow River Basin by using the Landsat series images (Landsat 5, 7, 8) and then examined the correlation between the accuracy of the water indexes and suspended particulate matter (SPM) concentrations. They proposed a surface water extraction method considering the SPM concentrations. The study by Heying Li et al. (contribution 2) has developed a quantitative evaluation model of surface water resource accessibility based on three key dimensions: topography, distance, and surface water resources, with rural settlements serving as the research unit.

In category B “Opportunities and Strategies for Management”, Yujun Wang et al. (contribution 3) have used compensation reservoirs to replace the emptied reservoir in undertaking water supply tasks as a constraint, established Single-objective optimization models for single reservoirs and multi-objective optimization models for reservoir groups, to optimize the emptying and dredging for water diversity reservoir group. In the study by Bingxuan Li et al. (contribution 4), an adaptive multiscale true 3D crust simulation platform using the Sphere Geodesic Octree Grid was proposed to offer reliable support for constructing basin simulation platforms and provided new technological and scientific insights for the Yellow River Basin’s ecological protection and development.

For the category C “Harmonious Regulation of Human–water relationships”, Zhiqiang Zhang et al. (contribution 5) selected the Yellow River water-receiving area of Henan Province as the research area, quantified the water security degree of 14 cities from 2010 to 2021, and identified the key obstacle indexes that restrict the improvement of water security. In the study by Lu Liu et al. (contribution 6), 29 evaluation indicators were selected and the single index quantification, multiple index synthesis, and poly-criteria integration method were applied to quantify the spatial–temporal variation in the human–water harmony degree in nine provinces of the Yellow River Basin from 2002 to 2021.

In category D “Environmental Pollution and Governance”, Zhenzhen Yu et al. (contribution 7) analyzed the water quality evolution in the Yellow River basin over nearly 40 years, focusing on primary pollutants like chemical oxygen demand (COD), ammonia nitrogen (NH₃-N), and permanganate index (COD_Mn). The findings underscored the effectiveness of sustained pollution control and the need for continuous, adaptive management strategies to improve and maintain water quality. The study by Zhenzhen Yu et al. (contribution 8) also conducted field monitoring at 11 locations along the investigated reach of Xiao Bei, assessing eight water quality parameters (temperature, pH, dissolved oxygen (DO), COD, NH₃-N, total phosphorus (TP), COD_Mn, and five-day biochemical oxygen demand (BOD5)).

In the category E “Ecological Restoration and Protection”, Jun Hou et al. (contribution 9) analyzed historical soil erosion trends (2000–2020), projected future soil erosion risks under multiple Shared Socioeconomic Pathways, and quantified the interactive effects of key driving factors by integrating the Universal Soil Loss Equation, future land use and vegetation cover simulation methods, and the Geodetector model. The study by Daiwei Zhang et al. (contribution 10) analyzed the coupled and coordinated development of the water–soil–energy–carbon system in the provinces of the Yellow River Basin from 2002 to 2022, and systematically explored the interaction relationships among the various factors through water–soil–energy–carbon bond index assessment, factor identification, and driving factor exploration.

3. Advances in Researching Core Scientific Challenges Within the Yellow River Basin

3.1. Synergistic Human–Water Relationship in the Yellow River Basin: Development and Future Vision

The Yellow River is widely recognized as one of the most difficult rivers to manage in the world. The spatial differences in geographical, climatic, and humanistic characteristics across the Yellow River Basin are significant, making it extremely challenging to balance the relationship between human and water [1]. Scholars have conducted extensive scientific research on the human–water relationship in the Yellow River Basin, with diverse and complex research objectives, scopes, directions, and scales [2,3]. Existing achievements hold substantial scientific value and practical significance for the protection and development of the Yellow River Basin [4,5]. However, regarding the complex, dynamic, and interconnected human–water relationship and based on the human–water system involving multi-element participation, multi-dimensional coupling, and multi-level feedback, in-depth exploration is still needed to achieve a harmonious human–water relationship. The key issues in the research on the human–water relationship in the Yellow River Basin mainly include four aspects: insufficient understanding of action mechanisms and evolution processes, inadequate research on theoretical foundations and the theory of harmonious coexistence, the need to deepen research on monitoring-assessment-simulation-regulation, and the need to expand multi-level paths toward harmonious coexistence. To coordinate the human–water relationship in the Yellow River Basin and achieve harmonious coexistence [6], future key research areas include but are not limited to the exploration of river ethics theory and system construction, the research and development as well as application of intelligent perception equipment for human–water system, the analysis of the formation mechanism and variation mechanism of water balance, the evaluation of the status of human–water relationship and paths for improvement, the adaptive adjustment of thresholds for water resources development and utilization, the integration and demonstration of key technologies for the “Defining the scales based on water”, the construction of distributed human–water relationship simulators, the construction of multi-level water networks and risk-benefit assessment, the optimization of water conservancy project layout and integrated operation management, and the exploration of new development paths under the rigid constraints of water resources.

3.2. AI-Driven Water Disaster Prediction for the Yellow River Basin

The Yellow River Basin faces numerous challenges in water disaster prediction research due to a combination of complex water-sediment dynamics, unique topographical features, variable climatic conditions, and intense human activity interventions [7,8]. These factors have historically resulted in low prediction accuracy, poor timeliness, and insufficient capacity for integrating multi-source information [9]. In recent years, with the breakthrough development of artificial intelligence technologies, research on water disaster prediction based on machine learning, deep learning, and big data analytics has gradually advanced in the Yellow River Basin [10]. Researchers have constructed multimodal data fusion frameworks that integrate heterogeneous data from meteorological satellite remote sensing, hydrological station observations, geological radar, and socio-economic sources. Algorithms such as Long Short-term Memory, Convolutional Neural Networks, and Random Forests were employed in hydrological process simulation [11], drought and flood monitoring [12], runoff prediction [13], and sediment management [14], and made significant progress. However, current research still faces several bottlenecks, including inconsistent data quality, weak interpretability of model physical mechanisms, and insufficient uncertainty quantification under complex underlying surface conditions. Future efforts should focus on strengthening interdisciplinary integration and developing simulation models that combine hydrological physical processes with data-driven approaches to enhance predictive capabilities for basin-level water disasters. Overall, the key challenges currently facing water disaster prediction research in the Yellow River Basin include the following: (1) elucidating the complex water-sediment coupling mechanisms in the Yellow River Basin and enhancing the generalization capabilities of AI models for extreme events in data-scarce contexts; (2) dynamic simulation of the Yellow River Basin under the coupled effects of intense human activities and climate change; (3) collaborative application of integrated “space, ground, and water” data in the Yellow River Basin; (4) constructing an intelligent decision-making system that encompasses the entire forecasting-warning-response chain. Moving forward, it is essential to deepen the construction of models that integrate physical mechanisms and data-driven approaches, develop intelligent supercomputing and digital twin platforms at the basin scale, establish intelligent predictive theories and methods for extreme flood events with small and zero samples, and construct adaptive learning and dynamic optimization intelligent early warning systems. Additionally, promoting interdisciplinary and interdepartmental collaboration in intelligent flood prevention and disaster reduction applications will provide robust technological support for ensuring the safety and resilience of the Yellow River.

3.3. Challenges and Strategies for Water Resource Efficiency and Intensive Management in the Yellow River Basin

The Yellow River Basin is characterized by weak natural endowments of water resources and pronounced spatiotemporal unevenness. With a water resources development and utilization rate as high as 80%, the basin has long faced the contradiction between increasing water demand and limited supply capacity. Achieving efficient and intensive utilization of water resources has therefore become the major challenge for ecological protection and high-quality development in the Yellow River Basin [15]. In recent years, scholars have conducted extensive discussions on the issues of efficient utilization and intensive management of water resources in the Yellow River Basin, covering a wide range of topics such as multi-sectoral water efficiency assessment [16], water resources optimal allocation of irrigation region [17], basin-scale regulation of water resources intensive utilization [18], and sustainable management strategies for basin water resources [19]. These research achievements provide valuable reference schemes and data support for integrated management and policy design of water resources in the Yellow River Basin. However, how to effectively integrate multiple dimensions including water resources, socioeconomic systems, and ecological environments under complex and changing conditions, and systematically plan strategies for efficient and intensive water resource utilization in the basin [20], still requires further exploration. In light of the realities of the Yellow River Basin, several key issues remain to be addressed: understanding the evolutionary mechanisms of water resource efficiency and driving forces of supply–demand imbalance; developing comprehensive measurement systems and integrated methodological frameworks for water resource efficiency; constructing dynamic regulation models for basin-scale water resource systems; innovating institutional frameworks and expanding management pathways for intensive water utilization. Consequently, future research priorities under this theme should include, but are not limited to: analysis of basin water system evolutionary mechanisms; integration and optimization of water resource efficiency measurement frameworks; development and coupled simulation of basin water resource regulation models; construction of efficient and intensive management models for basin water resources; simulation of synergistic policies for water resource efficiency and carbon emission reduction; and the design of coordinated development pathways for multi-dimensional systems under the rigid constraints of water resources.

3.4. Ecological Environment Protection and Intelligent Forecasting in the Yellow River Basin

With the increasing improvement of the Yellow River at the national strategic level, the relevant government regulatory authorities have also put forward more stringent requirements for ecological protection along the river basin. Compared with other large rivers in China, such as the Yangtze River and the Huaihe River, the Yellow River has a very high sediment concentration, which gives it relatively complex and changeable hydrological conditions [21]. In addition, suspended sediment plays a dual role in transmission carrier and reaction surface, which is of vital importance in the environmental behavior of contaminants [22]. Against this backdrop, growing scholarly attention has shifted toward integrated studies of hydrological prediction, coupled contaminant-sediment dynamics, and basin-wide ecological risk assessment. Over the past decades, the integration of satellite remote sensing, unmanned aerial vehicles, and in situ sensor arrays revolutionized data acquisition, yielding extensive, high-resolution records of hydrological and ecological processes [23,24]. These datasets, though abundant and of considerable potential value, have long remained underexploited due to technical limitations. The rapid emergence of artificial intelligence now provides new opportunities to unlock its utility. Graph neural networks, long short-term memory architectures, and physics-informed models have proven capable of capturing hydrodynamic complexity while adhering to conservation laws, thereby improving the precision of predictions for contaminant transport and transformation [25,26]. At finer scales, machine-learning frameworks grounded in chemical reaction networks, when coupled with semi-targeted chemical screening, can reveal transient intermediates that are often overlooked by conventional monitoring. Complementary tools such as quantitative structure–activity relationship models and Bayesian inference further extend this analysis, enabling early prediction of toxicological impacts [27,28]. Embedding these tools into basin-scale platforms would allow regulators to identify ecological risk in real time and strategically allocate limited resources to areas of greatest need. Although the vision is encouraging, there are still some obstacles in the current development. For example, the migration and transformation mechanism of contaminants on the sediment interface has not been well verified, which limits the interpretation basis of the prediction work. During extreme seasons, sediment dynamics will deviate from steady-state conditions, resulting in a decrease in prediction accuracy. In addition, there is insufficient integration between hydrology, ecology and computational science. Looking ahead, the coupling of machine learning with mechanism insight and high-resolution analysis technology can improve the accuracy and interpretability of prediction at the same time, which is helpful to change the management mode of the basin from passive restoration to predictive prevention.

3.5. High-Quality Development Path and Strategies

Research on the high-quality development of the Yellow River Basin has gradually established a multi-level and multi-dimensional theoretical framework, achieving notable progress in resource management, ecological restoration, and regional economic coordination [29,30]. Current studies mainly focus on the synergistic mechanisms between ecological conservation and economic growth, the innovative application of green technologies, and differentiated regional governance strategies [31,32,33], thereby providing essential scientific evidence and strategic guidance for the sustainable development. Achieving high-quality development of the Yellow River Basin, ensuring the effective implementation of strategic pathways and policies, and realizing the harmonious coexistence of the human–water relationship remain pressing issues requiring further in-depth investigation. At present, research in this field faces four critical challenges: (1) uncertainties in pathway selection hinder the implementation of development strategies; (2) the complexity of regionally differentiated governance prevents the establishment of unified management measures; (3) the mechanisms for coordinated development of the human–water system remain underdeveloped; (4) the application of emerging technologies in water resource management is still constrained. To explore feasible pathways and strategies for high-quality development of the Yellow River Basin and to achieve coordinated development of the human–water system [34], future research priorities should encompass, but are not limited to, the following areas: improve the theory and application of harmonious coexistence of “Defining the scales based on water”; intelligent water resource management and the application of big data; constructing a multi-system collaborative development mechanism for water resources, economy, society, and the ecological environment; optimizing the “supply-use” regulation pattern across multiple water sources, processes, and sectors in the basin; universal application of green technologies and digital management techniques; constructing intelligent water resource scheduling and multi-level management systems; improving the legal framework and policy safeguards for the Yellow River; water resource risk-benefit assessment and emergency management mechanisms; scientifically coordinating the relationship between water and development under the rigid constraints of water resources.

3.6. Construction and Efficient Management of Yellow River Water Conservancy Projects in the New Era

The Yellow River water conservancy projects, as the core infrastructure ensuring flood control safety, water resource supply, and ecological stability in the Yellow River Basin [35], face severe challenges in the new era from climate change, accelerated urbanization processes, and high-quality development demands [36]. Scholars have conducted a large amount of scientific research on the construction and management of Yellow River water conservancy projects, covering aspects such as project planning, construction technology, risk assessment, operation scheduling, and benefit evaluation [37,38]. The existing results have significant scientific value and practical significance in enhancing project resilience, optimizing water resource allocation, and promoting sustainable development [39,40]. However, focusing on the complex and changing engineering systems in the context of the new era, how to achieve green, intelligent, and efficient construction and management of water conservancy projects still requires further deepening. The key issues in the research on Yellow River water conservancy project construction and efficient management include four aspects: insufficient understanding of the establishment of technological innovation and adaptability mechanisms, lack of research on green development theory and integrated operation and management systems, the need to strengthen digital twin simulation technology, and the need to expand multi-level risk prevention and control and benefit enhancement paths. To achieve high-quality development of Yellow River water conservancy projects in the new era, future key research areas include but are not limited to the following aspects: exploration and practical application of green low-carbon water conservancy project theories, analysis of resilience formation mechanisms and climate change adaptation for water conservancy projects, innovation in integrated operation and management modes for water conservancy projects under digital transformation, exploration of sustainable utilization of water conservancy project materials and green development modes, simulation and quantification of multi-disaster coupled risks caused by water conservancy project construction, integrated technology for “monitoring-evaluation-assessment” coupling of water conservancy project construction effectiveness, construction of integrated platforms for intelligent supervision and early warning of water conservancy projects, research and development of health diagnosis technology for water conservancy projects under multi-source data fusion, and research on linkage regulation mechanisms for cross-basin water conservancy projects.