Extreme hydrological drought exacerbates water supply-demand imbalances, especially in water-scarce river basins. Therefore, assessing the impacts of such imbalances in the context of extreme hydrological drought is crucial. This study develops a three-dimensional social-economic-ecological assessment framework to evaluate these impacts under an extreme hydrological drought scenario, incorporating indicators of social impact deviation, expected economic loss, and emergy-based ecological value loss. On this basis, a composite impact index is constructed using a relative-entropy-based combination weighting method. The Henan Yellow River water-supply area in China is selected as a case study to evaluate the impacts under this scenario. The results show that high-impact cities are clustered along the Yellow River's main stem, forming a continuous high-value belt. The ecological dimension contributes slightly more to the overall impacts than the social and economic dimensions. High-impact cities show both high economic and ecological value losses, whereas moderate-impact cities are typically dominated by a single dimension. As drought severity increases from moderate to extreme hydrological drought, the composite impact index generally increases across the study area. The comprehensive impacts are shaped by regional water resources, industrial structure, water allocation, and water-use structure. The findings provide quantitative support for zoned regulation of water supply-demand imbalance risks.

Addressing the issues of insufficient consideration for non-market ecosystem services and unclear definition of compensation control thresholds in forest ecosystem compensation, in this paper a regional ecological compensation mechanism oriented toward securing forest ecosystem service functions was proposed. Based on emergy analysis and integrated with multidisciplinary methods, a quantitative evaluation framework for forest ecosystem service functions was established. The M-K and Pettitt methods were jointly applied to the interannual sequence of functional benefits to identify abrupt changes and determine the compensation control threshold. A coupled humannature emergy system was constructed to trace ecological and economic flows within and beyond the system, compensation standards (i.e., the unit emergy value of forest resources) was defined, and the value compensation relationship between humans and forest systems was quantified with the constraint of functional benefit thresholds. This study provided a new perspective for forest ecological compensation research. The proposed theoretical framework and methodology were applied to Luoyang City in Henan Province. Results showed that the total emergy benefits of forest ecosystem functions exhibited a steady upward trend from 2010 to 2021, with a cumulative increase of 0.37%. The year 2016 was identified as the mutation point, with a compensation control threshold of 5.11E+22 sej. The years 2010—2015, during which the functional benefits were below the threshold, required compensation. During this period, the total compensation value showed a fluctuating decline, decreasing from 37.71 million yuan in 2010 to 12.64 million yuan in 2015. The compensation value was primarily driven by the magnitude of functional benefit reduction below the threshold, which was closely linked to the abundance of key ecological elements within the forest system. Therefore, continuously enhancing forest protection and sustainable management was essential to realize the goal of harmonious coexistence between humans and nature.

The Yangtze River Basin, China’s most vital river system, faces increasing ecological and resource pressures. By integrating emergy theory with spatial autocorrelation and the breakpoint theory within a coupling field intensity model, this study establishes a framework to quantify cross-regional ecosystem service spillovers across forest, grassland, and water eco-subsystems. The results reveal that from 2000 to 2020, the emergy of natural ecosystem services exhibited an initial decline, followed by an increase and then a slight regression, primarily influenced by the water eco-subsystem. Forests were the dominant contributor with a rising trend, while grasslands exhibited periodic fluctuations influenced by urbanization but demonstrated positive development potential when aligned with urban planning. The results also indicate that ecosystem service spillovers showed a rising trend with basin-wide distribution. Forests exhibited the highest spillover levels, with high-quality ecological areas concentrated in the southwest, while grasslands in the northwest showed notable growth. Water eco-subsystem services, mainly clustered in the northeast, reached their lowest spillover level in 2020 due to the spatial dispersion of water storage services, reflecting an improved spatial distribution of water resources over time. These findings provide valuable insights for enhancing the Yangtze River Basin’s ecological resilience, promoting ecosystem preservation, and supporting sustainable development.

IntroductionIn recent years, industrial and agricultural advancements in Henan Province have increased heavy metal contamination in rice, raising public concerns. The aim of this study was to investigate the contamination levels of five heavy metals, cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and inorganic arsenic (As), in rice from Henan Province and to assess potential health risks.MethodsA total of 6,632 rice samples were collected from 18 regions between 2020 and 2022. The samples were analyzed for Cd, Cr, Pb, Hg, and As using inductively coupled plasma mass spectrometry (ICP-MS). Detection rates were compared using the chi-square test, and health risks were assessed for the three populations (adults, children and toddlers) according to USEPA guidelines.ResultsThe results of the study showed that As had the highest detection rate of 99.59%, followed by Cd (27.69%), Cr (22.57%), Pb (2.25%) and Hg (1.95%). Cd levels were significantly higher in urban areas (30.42%) than rural areas (23.13%) (P < 0.001). The detection rate of Cd was higher in the southern region compared to other regions, while the detection rate of Cr in the eastern region was the highest among all regions. The health risk assessment showed that the Hazard Quotient (HQ) for inorganic As exceeded 1. However, children and toddlers were at relatively higher risk of exposure to As compared to adults.ConclusionThis study revealed the current status of heavy metal contamination in rice in Henan, particularly highlighting the presence of As as a significant health hazard for children and toddlers. Consequently, it is recommended that the relevant authorities should strengthen the monitoring and control of food safety in order to effectively protect public health.

Urban flooding has posed significant challenges to urban development due to the global climate change and the urban construction process. Timely and accurate warning information is crucial to reduce impacts of floods. However, few studies have explored the linkage of rescue activities with early warning information. Therefore, a joint warning mechanism considering anthropogenic relief activities and urban flood risk was proposed. First, the comprehensive flood risk results were obtained by using analytic hierarchy process-fuzzy evaluation with data on flood depth, population density, characteristics of disaster bearing bodies, and land average GDP. Then, the two-step floating catchment area method was improved to analyze the rescue accessibility. Finally, the joint warning results were obtained through two-dimensional table method to achieve warning while preserving the characteristics of the basic information of relief and flood risk. A practical application in the Jinshui District, Zhengzhou city was used to confirm the rationality and feasibility of the proposed method. The results revealed that areas labeled as efficient rescue covered 23.83% of the high risk area under 100a return period rainfall, which needed be improved. The research results provide a scientific reference for the actual rescue work.

Flood disasters cause severe economic losses, and understanding their spatiotemporal distribution is crucial for effective disaster prevention and mitigation. This study introduces a flood impact index (FII), derived from direct economic losses and the affected population, and employs a dynamic clustering framework to investigate its spatiotemporal characteristics. The framework automatically determines the optimal number of clusters for each year using a data-driven approach based on the Calinski–Harabasz (CH) index and mode analysis, and then applies hierarchical clustering with variance-based splitting and merging to ensure temporal consistency. The results indicate that (1) from 1993 to 2023, the overall impact of floods in China has exhibited a declining trend; (2) spatially, flood impacts are primarily concentrated in the central and southern regions of China, while the northern regions experience comparatively minor effects; and (3) within the study area, some regions experience either severe or minimal flood impacts and remain relatively stable, while regions with moderate flood impacts exhibit greater fluctuations. This study enhances existing spatiotemporal analysis methods and provides policymakers and planners with a robust quantitative foundation for improving flood prevention and mitigation strategies.

There is no evidence on the associations between persistent organic pollutants (POPs) and the incidence of chronic kidney disease (CKD) in the Chinese rural population. We aimed to investigate the individual and mixed effects of 22 POPs on the prevalence and incidence of CKD, and the joint effects of POPs and abnormal glucose metabolism as well as the modification effects of healthy lifestyle on these associations. A total of 2775 subjects, including 925 subjects with normal plasma glucose (NPG) and 925 subjects with prediabetes (PDM) and type 2 diabetes mellitus (T2DM), were enrolled from the Henan Rural Cohort Study. Logistic regression and quantile gcomputation were performed to assess the individual and mixed effects of POPs on the risk of CKD. Joint effects of POPs and abnormal glucose metabolism status, as well as the modification effects of lifestyle on CKD were assessed. After 3-year follow-up, an increment of ln-o,p'-DDT was related to an elevated risk of CKD prevalence. Positive associations of p,p'-DDE and (3-BHC with CKD incidence were observed (P < 0.05). In addition, participants with high levels of & sum;POPs were associated elevated incidence risk of CKD (OR: 1.217, 95%CI: 1.008-1.469). One quartile increase in POPs mixture was associated with the increased incidence of CKD among T2DM patients (P < 0.05). Further, a higher risk of CKD was observed among PDM and T2DM patients with high levels of o,p'-DDT, p,p'-DDE, (3-BHC, and & sum;POPs than NPG subjects with low levels of pollutants. In addition, interactive effects of & sum;POPs and lifestyle score on CKD incidence were found. Individual and mixed exposure to POPs increased the prevalence and incidence of CKD, and glucose metabolic status exacerbated the risk of CKD resulting from such exposures. Further, the modifying effects of lifestyle were observed, highlighting the importance of precision prevention for high-risk CKD population and healthy lifestyle intervention measures.

The southwestern mountainous and hilly regions of China are vital ecological barriers upstream of the Yangtze River. Assessing and simulating changes in ecosystem service value (ESV) in this area is essential for ensuring sustainable ecological development. In this study, our purpose was to evaluate and simulate the spatial patterns as well as trends in the changes shown by the ESV in Yanting County, China, from 2020 to 2030 via a grid-scale using the equivalent factor method and the Markov-patch-generating land use simulation model. The results indicated that (1) from 2020 to 2030, forest, cultivated, and construction lands would be the main types of land use. (2) In 2030, the projected ESVs in Yanting County under the as-usual, low-carbon, and shared development scenarios were 5.31, 5.30, and 4.99 billion RMB, respectively. Compared to the 2020 ESV of Yanting County, the as-usual scenario and low-carbon scenario ESVs increased. The shared development scenario ESVs decreased. It reflects the contra-diction between urbanization, industrialization, agricultural production, and ecological protection in Yanting County. The spatial distribution of the ESVs of all three scenarios showed an agglomeration trend. (3) Given the background of national food security and carbon peaking and carbon neutrality, the setting of a low-carbon development scenario combined with a shared development scenario appears to be more suitable for the future development of Yanting County, which is conducive to the rational planning of land-use patterns and the sci-entific growth of ESV in Yanting County. This study underscores the critical importance of integrating ESVs in sustainable land-use planning and management, and provides a reference for the rational use of land resources, land spatial planning, and policy-making for ecological protection in Yanting County.

River ecological protection and rational utilization of water resources provide an important support for the sustainable development for human beings and nature. In view of the lack of ecological compensation research on river ecological water demand and socio-economic water demand, a mechanism and methodology for ecological compensation based on the synergistic control of river ecological water demand and river water rights allocation is proposed. The variable monthly flow method and the improved dynamic calculation method are applied to obtain the river basic and suitable ecological water demands as the river protection threshold. A twolayer decision model for water rights allocation is established, which realizes the cascading allocation of initial water rights from city to counties to sectors, and the socio-economic water usage threshold for each level is obtained based on the model. Developing compensation discrimination guidelines under the dual-threshold synergistic control and using the unilateral water resources value by sub-sector as the compensation standard, realize the quantification and sharing of compensation funds. The Nanyang section of the Bai River basin in China is used as an example. The ecological compensation value for wet year (2011), normal year (2012), and dry years (2014-2013) are 0, 15.09 x 10(8) and 12.04 x 10(8) (average value for dry years) RMB. The adoption of suitable ecological water demand thresholds in 2012 increases the ecological protection requirements thus leading to an internal compensation situation between Nanyang County and Xinye County. From 2014 to 2016, river runoff continued to be low, and excessive water intake from upstream lead to a chain of compensation situations in the midstream and downstream. It is essential to establish a basin and regionally nested ecological compensation mechanism. The research results are conducive to improving the eco-compensation theory and provide scientific references for water resources management and high-quality development in the basin.

With the emphasis on preventing urban flooding and the enhancement of rational urban development, data related to urban flooding are also collected with unbalanced sample size that is a widespread phenomenon in other world fields. The performance of the classification model is compromised by unbalanced datasets, therefore, minority-class samples, floods with higher risk, are often missing alerted or incorrectly warned. To solve this problem, a novel hybrid resampling proposal is proposed in this research proved to be effective for balancing data. First, it optimizes an imbalanced dataset by the Borderline-SMOTE algorithm. Next, alternative datasets are synthesized through under-sampling techniques, whose qualities are evaluated by using information entropy and calculated rely on the k-nearest neighbor entropy estimator. The suggested method not only makes full use of the original data information, but also avoids under-fitting due to the single under-sampling utilization. A practical application in the central area of Zhengzhou, China, combining the resampling proposal and the Random Forest classification model optimized by Genetic Algorithm, the results show that significantly better results are yielded compared without any treatment in terms of all assessment indicators (Accuracy, Recall, G-mean and F1-score) have been improved.

Dangerous substances are extremely chemically unstable during storage, and their hazardous properties, such as being flammable, combustible, and corrosive, have stringent storage environment requirements. To strengthen the real-time monitoring of a dangerous goods warehouse, this paper employs IoT technology to design an intelligent monitoring system, selecting ZigBee tree topology to establish a wireless communication link, connect sensor devices, and complete the collection and transmission of monitoring data. In the meantime, the NB-IoT communication module connects to the IoT cloud platform to enable comprehensive remote control and data interaction with monitoring equipment. Through the design of an ethanol monitoring system, experimental cases demonstrate that the system satisfies the requirements for a hazardous materials warehouse monitoring system.

Eco-compensation is an important means to implement the rights and responsibilities of ecological protection and alleviate the water conflicts inside and outside the river. Previous studies focused on water conflicts among users, overlooking the government's regulatory role in the eco-compensation mechanism and the coordinating function of water transfer compensation fees among users. This study constructed a tripartite evolutionary game model involving government regulatory agencies (GRA), in-channel ecological environment water demanders (EEWD), and off-channel socio-economic water users (SEWU). The evolutionary stability strategies (ESS) of the GRA, EEWD, and SEWU and the evolutionary trend of the tripartite system were analyzed using the finite rationality evolutionary game model, and the sensitivity analysis of the influencing factors was conducted using the eigenvalues of the Jacobi matrix and numerical simulation. Taking the Bai River Basin in Nanyang, China, as the case study, the results showed that the GRA's rewards and penalties were controlled within a reasonable range can promote the enthusiasm of the participating subjects in the water quantity compensation mechanism; water quantity compensation standard for the SEWU was an important indicator for the smooth implementation of the compensation mechanism, the loss coefficient and the overall ecological benefit allocation coefficient of the EEWD will influence the formulation of water quantity compensation standards. This suggested that the GRA should enhance the management of the eco-compensation-related policies and laws and regulations, limit the SEWU's eco-compensation standard, and improve the net benefit of EEWD, to achieve the optimal eco-compensation strategy of ''supervision, protection, compensation''. The research results provide a reference value for the formulation of the water quantity eco-compensation mechanism for water use coordination inside and outside the river.

Global value chain (GVC) is not only value-added distribution chain but also pollution-sharing chain closely related to benefit distribution. With the deepening of firms participating in GVC and under the burden of severe environmental pollution, There is a question on our minds, that is whether smile curves in global value chains bring crying curves in pollution chains. This paper empirically tested the relationship between GVC participation and environmental pollution from firm-level perspective, using the matching data of the China Industrial Firms Database, China Firms Pollution Database, and UIBE Database from 2000 to 2012. The results show that the GVC participation and GVC length have different effects of environmental pollution. GVC participation have negative effects of pollution, while GVC length have positive effects of pollution. Both effects of environmental pollution are influenced by GVC models. This paper provide policy suggestions for environmental protection from the perspective of adjusting GVC participation strategy.

With the warming of the global climate and the acceleration of urbanization, the intensity and frequency of urban floods pose increasingly significant threats to cities. The prediction of urban flood depth is an important non-engineering measure used to mitigate the hazards associated with urban flooding. In this study, a novel approach based on the XGBoost-SHAP is proposed to predict the urban flood depth, which compensates for the black-box shortcomings of the single XGBoost model and performs a global interpretation of the selected predictive factors. Meanwhile, Genetic Algorithms (GA) are employed to achieve the optimization of XGBoost model parameters. This approach is applied to a case study in Zhengzhou city, China, an area prone to frequent flooding due to its extensive built-up regions. The results suggest the Root Mean Square Error (RMSE) and Nash-Sutcliffe Efficiency (NSE) between observed and predicted values of urban flood depth are 0.065 and 0.885, which satisfy the demand. Besides, the results of relevance and significance analysis indicate that rainfall factors are more closely linked to flood than geographical factor. The results provide a reference for urban flood forecasting, factor analysis and the development of disaster reduction measures.

The risk assessment of urban flood disasters (UFRA) is an effective way to prevent urban disasters, which plays an important role in risk management. Urban floods have occurred frequently in recent years, it is necessary to carry out research on UFRA. Considering four main factors: disaster-pregnant, disaster-causing, disaster-forming, and disaster-curing, this paper established a risk assessment model for urban flood disasters. Firstly, constructing a city flood risk assessment index system, and calculating the optimal combination weight (CW) by determining the subjective weight (SW) and objective weight (OW). Secondly, by using the cloud model to reveal the uncertainty relationship between evaluation indexes and level, the comprehensive UFRA was obtained. Rainfall and water information of all kinds of building types could be collected through cloud model and SWMM, the index system of the disaster-causing information by GIS was improved. Taking the 100-year return period rainfall in the central urban area of Zhengzhou City as an example, the comprehensive flood risk level was obtained, and the factors contributing to the risk in each region were analyzed. The results indicated that Jinshui District (JD) was at a high risk level and all other districts in Zhengzhou were at a sub-high risk. This model provides new insights for flood risk management.

High accuracy prediction of urban flood risk is conducive to avoid potential losses, however, it's negatively affected by unbalanced data. Furthermore, ensemble model has been demonstrated to have the ability to improve to prediction accuracy. Nevertheless, the performance of ensemble model is influenced by basic model and ensemble rules, and determining the best ensemble model remains an open issue. To improve the accuracy of flood risk prediction, an approach covering data optimization and ensemble modeling was presented to optimize unbalanced flood data and the selection of various ensemble models based on efficiency and performance. A practical application in Zhengzhou City shows that Borderline-SMOTE2 is the most applicable for optimizing the flood risk data among the state-of-the-art oversampling algorithm utilized, because of the excellent entropy value. The effect of unbalanced data on the performance of the basic models was pervasive according to changes of the common indicators. The optimal ensemble model for flood risk prediction is composed of K-Nearest Neighbor, Decision Tree, Gaussian Naive Bayes and Extreme Gradient Boosting under Stacking rule in the current study. The results of this study supply the valuable reference for the flood prediction and mitigation.

The risk assessment of urban flood disasters (UFRA) is an effective way to prevent urban disasters, which plays an important role in risk management. Urban floods have occurred frequently in recent years, it is necessary to carry out research on UFRA. Considering four main factors: disaster-pregnant, disaster-causing, disaster-forming, and disaster-curing, this paper established a risk assessment model for urban flood disasters. Firstly, constructing a city flood risk assessment index system, and calculating the optimal combination weight (CW) by determining the subjective weight (SW) and objective weight (OW). Secondly, by using the cloud model to reveal the uncertainty relationship between evaluation indexes and level, the comprehensive UFRA was obtained. Rainfall and water information of all kinds of building types could be collected through cloud model and SWMM, the index system of the disaster-causing information by GIS was improved. Taking the 100-year return period rainfall in the central urban area of Zhengzhou City as an example, the comprehensive flood risk level was obtained, and the factors contributing to the risk in each region were analyzed. The results indicated that Jinshui District (JD) was at a high risk level and all other districts in Zhengzhou were at a sub-high risk. This model provides new insights for flood risk management.

Different sub-regions of Zhengzhou city have various levels of sensitivity to flood due to the impact of urbanization. Thus, an accurate flood sensitivities assessment is a key tool for flood prevention and urban planning and development. To successfully link the urban flood sensitivity assessment with the real flood situation, a method combining clustering algorithm with comprehensive evaluation is presented. The proposed method is not affected by the classification standard of sensitivities levels and has a small and undemanding demand for flood data. First, Maximal Information Coefficient between conditional factors and flood is employed to determine the weight. Then, the different results are obtained by three clustering algorithms. Finally, a four-layer evaluation structure weighted by analytic hierarchy process is established to select the best flood susceptibility map. A case study in the Zhengzhou city, China shows that the positive scale amplification strategy is relatively best and the flood sensitivity of sub-regions in Zhengzhou city should be divided into four levels obtained by K-Means clustering. Hence, it supplies the valuable insights for the urban planning and flood mitigation.

Watershed ecological compensation is an effective economic policy measure for water ecology conservation and water environment management. This study constructed an eco-compensation mechanism under the double control of water quality and quantity, which consisted of the water quality control module, the water quantity control module, and the double control compensation value module. The pollution loss water quantity and the river habitat compensation water quantity were calculated, and the water quality achievement or excess and water quantity surplus or deficit were identified to divide the multi-scenario compensation mode and obtain the double control compensation value. The Bai River Basin in Nanyang, China, was selected as the case study, and the double control compensation value of the three counties in the basin was calculated from 2015 to 2018. The results showed that the water quantity compensation value of all counties was higher than the water quality compensation value, indicating that the water quantity has a greater impact on the water environment compared with water quality, and the ecological water demand of rivers needs to be guaranteed while strengthening water pollution treatment. The compensation mode all belonged to the double control mode. The double-control compensation mechanism had a distinct advantage over the single-control compensation, indicating that water quality and quantity should be considered in the compensation programs to maintain healthy ecological conditions in the water supply. The research results provide ideas for the quantification of eco-compensation and the formulation of long-term ecological protection mechanisms.

[Objective] The value change and radiation effect of the regional aquatic ecosystem service function were analyzed in order to provide a scientific basis for sustainable development of regional water resources and ecological compensation of a river basin. [Methods] ArcGIS software was used to extract land use data for Luoyang City, Henan Province from 2000 to 2020 in order to obtain the area of water type. The emergy method was used to quantify and analyze the changes of aquatic ecosystem service functions, and the functional radiation was analyzed by the break point model. [Results] From 2000 to 2020 (in five-year time steps), the total emergy values of aquatic ecosystem services at Luoyang City were 8.01×1021 sej， 1.29×1022 sej， 1.27×1022 sej， 1.29×1022 sej， and 1.31×1022 sej, respectively, with a general increasing trend. Among these emergy values, the focus of service composition had shifted from supply function to cultural function. In this system, biodiversity protection, aquatic product production, water resource supply, water resource regulation, and leisure and entertainment functions were dominant. Leisure and entertainment functions have become core functions. In addition, the main transfer areas of the aquatic ecosystem service function in Luoyang City were Songxian County and Luoning County, with total outward transfer values of 3.10×1020 sej and 3.21×1020 sej, respectively. The main transfer areas were Luanchuan County, Yiyang County, Yichuan County, and Ruyang County. [Conclusion] Greater attention will need to be given to ecological protection of water, increasing support and guidance for regional tourism, and reasonably carrying out ecological compensation in areas similar to Luoyang City to promote the coordinated development of the economy, society, and ecology in various regions.