Although blood transfusion eco-compensation-a metaphorical term in the Chinese eco-compensation literature referring to short-term direct compensation-can balance stakeholder interests in securing ecological flows (e-flows) in water-scarce rivers, it often fails to enhance the productivity of disadvantaged stakeholders or expand long-term development opportunities. To overcome this limitation, this study introduces hematopoiesis eco-compensation, a metaphorical term for capacity-building, longer-term development-oriented compensation that improves irrigation water-use efficiency and agricultural productivity through water-saving infrastructure upgrades, enhanced irrigation technologies, and technical training. Based on this distinction, we developed a hybrid eco-compensation mechanism integrating the two approaches using a cost-expenditure method and applied it to the mainstream section of the Weihe River and the Baojixia Yuanshang Irrigation District in Northwest China under typical hydrological conditions. The main findings are as follows: (1) Compensation standards for both approaches increase with higher ecological flow targets, with average values of 2762 CNY ha-1 and 1386 CNY ha-1, respectively. (2) The two approaches differ in terms of participants, standards, and implementation methods, yet they are complementary and indispensable under current conditions. (3) Hematopoiesis eco-compensation generates positive ecological and economic effects, increasing the annual value of riverine ecosystem services by approximately 126 million CNY and the annual economic benefits of the irrigation district by approximately 467 million CNY. This study provides a theoretical foundation and practical guidance for establishing long-term compensation mechanisms to maintain ecological flows in water-scarce regions.

Agricultural non-point source pollution (ANPSP) represents a major threat to water quality, yet its spatiotemporal dynamics in arid and semi-arid regions remain poorly quantified. This study establishes an integrated assessment framework to analyze the spatiotemporal patterns and driving mechanisms of ANPSP in Inner Mongolia, China, from 2002 to 2023. Using a combination of inventory analysis, pollution load equivalence assessment, and the Tapio decoupling model, we systematically examined the evolution of four pollution sources-chemical fertilizers, livestock breeding, agricultural solid waste, and rural domestic discharge-across 12 administrative regions. These methods were sequentially applied to quantify loads, standardize impacts, and evaluate the economy-environment relationship, forming a coherent analytical chain. Key results indicate the following: (1) Pollutant loads increased consistently over the study period, with chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) rising by 24.21%, 31.67%, and 31.14%, respectively, largely driven by livestock sector expansion. (2) Spatial distribution was highly heterogeneous, with Tongliao, Chifeng, and Hulunbuir contributing 50.58-58.31% of total emissions, in contrast to minimal impacts in western regions. (3) Decoupling analysis indicated variable environment-economy relations, where fertilizer use and grain output reached strong decoupling in 2010-2011 and 2018-2019, whereas livestock pollution exhibited more unstable decoupling trajectories. A cluster-derived risk zoning scheme identified Bayannur as the only high-risk area and highlighted the need for tailored management approaches in medium- and low-risk zones. This study offers a scientific foundation for targeted ANPSP mitigation and sustainable agricultural strategy formulation in ecologically vulnerable areas.

The response mechanisms and quantitative analysis of runoff pollution reduction, accumulation effect of pollutants in media, and plant physiological characteristics for bioretention systems remain inadequately investigated. In this study, we constructed pot-scale systems with a mixture of [soil + sand + leaf litter compost + Ophiopogon japonicus], and designed the inflow condition by L39 orthogonal combinations under the impact conditions of runoff pollution load from different functional zones/underlying surface. The indicators of inflow/outflow, media, and plant aboveground and underground parts were tested. The results showed that the bioretention systems under different pollutants load impacts had a significant effect on runoff ammonium nitrogen (NH4+-N), total phosphorus (TP), and chemical oxygen demand (COD), with load reduction rate of 11.9%-71.8%, 8.3%-43.7%, 5.1%-30.1%, respectively. Significant leaching was observed with nitrate nitrogen (NO3--N) and total nitrogen (TN). The results of multiple linear regression analysis showed that the load reduction of carbon, nitrogen, and phosphorus (C, N, and P) in runoff is positively correlated with their inflow concentrations (R2 > 0.8), and the interaction between them is not significant. Under different inflow load impacts, the variation ranges for chlorophyll, malondialdehyde, and biomass are 63.4%, 77.4%, and 59.8%, respectively. The growth of plants is mainly influenced by the inflow concentration of C and N. The research results contribute to a deeper understanding of the impact of incoming pollutant concentrations on bioretention systems, and are helpful for the long-term management of bioretention systems and the assessment of potential risks.

Mining activities have increasingly become an important source of heavy metals (HMs) pollution, yet research on coexistence patterns and interactive mechanisms of microorganisms, antibiotic resistance genes (ARGs), and metal resistance genes (MRGs) under long-term HMs pollution is limited. This study combined heavy metal analysis and molecular biology techniques to comprehensively evaluate the impact of HMs accumulation on resistance genes and microbial community structure along Wenyu River flowing through the Jindui molybdenum mine in Shaanxi Province. The results showed that the sediments of the Wenyu River were heavily polluted by Cd, Cu, and Zn, with average concentrations 14.8, 11.8, and 4.1 times higher than the background values of HMs in Qinling metallogenic belt, respectively. The abundances of ARGs were significantly correlated (R = 0.638 -0.806, p < 0.05) with the concentrations of HMs. Moreover, heavy metal pollution led to changes in microbial diversities in the river sediments that were gradually dominated by higher HM-tolerance microbial species (e.g., Aquabacterium and Novosphingobium). Network and Procrustes analyses showed that multiple resistance of host bacteria was widely present, and significant correlation (M2 = 0.5942, p < 0.05) was observed between the compositions of sediment microbial communities and ARGs, indicating that the composition of microbial community in Wenyu River may potentially be the driving force for ARG transmission. The research outcomes provide a basis for exploring the adaptative mechanism of microorganisms in aquatic environments during the long-term pollution of multiple heavy metals.

With the advancement of sponge city construction, rain gardens, as key facilities for concentrating and infiltrating rainwater runoff, have been widely established. However, the accumulation of heavy metals (HMs) in the fillers and the associated pollution risks cannot be ignored, which have a significant impact on the operational lifespan of these facilities. This study took the observation point (P) within a rain garden that has been in operation since 2012 and the control point (CK), which is the soil sample collection point in the natural infiltration area, as samples. Based on the monitoring data of HM content from 2017 to 2022, the pollution characteristics of Cu, Zn, and Cd were analyzed using enrichment factors and the geo-accumulation index, and the potential ecological risks were evaluated to reveal the impact of concentrated infiltration of runoff. The results showed that Cu and Cd accumulated in the 0–10 cm depth, while Cu and Zn exhibited seasonal annual variations, and the variation of Cd was not obvious. The study found that Cu and Zn were in a non-enriched state, while Cd was slightly enriched. Among the single ecological risk factor indices, the pollution levels of Cu and Zn were low, while that of Cd was relatively high. Comparison of the data from the observation point and the control point reveals that 88.9% of the data points of single ecological risk factor indices at each soil depth at the observation point are higher than those at the control point, revealing the impact of concentrated infiltration of rainwater runoff on the soil. However, the comprehensive assessment indicated that the overall ecological risk of the soil in the rain garden and the natural filtration area was at a low level. Nevertheless, given that the long-term operation of rain gardens may still pose pollution risks to the soil and groundwater, it is imperative to take timely measures to control HM pollution to ensure the long-term stable operation of sponge city facilities and the safety of the ecological environment.

【Objective】The implementation of ecological compensation for the protection of river ecological base flow often faces challenges due to inconsistent management practices. Variations in land production capacity across large irrigation areas, along with concerns from affected farmers about the fairness of a uniform ecological compensation standard, are key issues. This study aims to address these challenges. 【Method】 Grain yield per unit area was used as a key indicator of land production capacity, which was used to develop a corrected model for ecological compensation standards aimed at protecting river ecological base flow. The model was applied to the Baoji section of the Weihe River basin as a case study to demonstrate the corrected ecological compensation model. 【Result】The key findings are as follows: ① The revised model is rational and feasible based on the analysis. ② The ecological compensation standard for protecting the river’s ecological base flow is 234.64 yuan/mu. ③ A quantitative relationship between grain yield per unit area and the modified ecological compensation standard for affected farmers was established. ④ The advantages and limitations of the modified compensation model are discussed.【Conclusion】This study provides a theoretical foundation and technical support for refining ecological compensation standards for the protection of river ecological base flows, especially in water-scarce regions of Northwest China.

More than half of the world's highly regulated rivers are currently experiencing an unsustainable balance between ecological protection and economic development. The value realization of river eco-products is considered a key pathway to addressing this challenge; however, its effectiveness remains to be empirically verified. Therefore, the objective of this study is to develop an integrated framework for evaluating the sustainability of river ecological protection and economic development through eco-product value realization. The framework integrates the classification of river eco-products, the estimation of their potential and realized values, and the analysis of value realization pathways. Taking the Baoji section of the Weihe River (BSWHR) as a case study, the framework is applied with hydrological, hydraulic, and socio-economic datasets to empirically evaluate the coordination between ecological protection and economic development. The main results showed that: (1) River eco-products are divided into three types: public, operational, and physical operational eco-products; (2) The potential ecological value of all river eco-products in the BSWHR is estimated at 549 million CNY; (3) The realized value of all river eco-products is 288.75 million CNY under current realization paths, corresponding to a sustainability index of 0.63, indicating that the BSWHR is less sustainable and represents an asset liability river; and (4) Enhancing the protection level of river ecological flow (e-flow) and establishing a multi-stakeholder compensation mechanism can improve the sustainability of ecological protection and economic development in highly regulated rivers. The proposed framework provides a practical basis for assessing river sustainability and guiding the effective allocation of ecological protection funds.

Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) has been widely used in rocket propulsion, military, artillery manufacturing, and mining industries. However, HMX exhibits high toxicity and is difficult to biodegrade, which may cause serious environmental pollution. In this study, Fenton oxidation was employed to treat HMX wastewater, and the degradation performance under different conditions, as well as the degradation mechanism and toxicity changes, were investigated. The results showed that the degradation performance reached its optimum under reaction conditions of pH = 3.0, H2O2 concentration of 30.0 mmol/L, and Fe2+ concentration of 0.7 mmol/L, with a removal rate of up to 90.8

Mining activities have emerged as an important source of heavy metals (HMs) pollution in receiving watersheds, yet the ecological risks of HMs are primarily assessed using index-based methods with metal concentrations, lacking toxicity evaluation from a molecular biological perspective. This study integrated geochemical assessments with toxicogenomics assays to comprehensively evaluate the HMs contamination in a receiving watershed (Wenyu River and Luo River) affected by acid mine drainage (AMD). Results showed that the average concentrations of six HMs (Fe, Mn, Zn, Cu, Pb, and Ni) in surface water samples exceeded the environmental quality standards in China, and the average concentration of Fe was 28.9 times higher than the regional background values. The concentrations of Mn, Zn, and Cu in sediments ranged in 736.7-1654.6, 123.4-789.2, and 27.4-1114.0 mg center dot kg- 1, respectively. Geochemical calculation showed that both surface water and sediments of the receiving watersheds were contaminated with HMs. Principal component analysis and cluster analysis suggested that Co, Zn, Cd, Cu, and Pb in sediments were likely of anthropogenic origin, whereas Cr, Ni, Mn, and As appeared to derive primarily from natural erosion processes. The highest toxicity level of 1.63 +/- 0.09 as PELItotal was observed at sampling site W7 located downstream of the Wenyu River. Exposure to HMs pollution induced up-regulation of functional genes in yeast cells associated with chemical and oxidative stress pathways. This study provides a scientific basis for health risk assessment and the development of targeted mitigation strategies for HMs pollution in watersheds impacted by AMD.

Co-pyrolysis technology is considered to be one of the most promising methods for the sustainable utilization of biomass wastes, as it can realize waste reduction and convert wastes into high-value-added products with little impact on the environment. The evaluation of thermal characteristics and product properties is necessary for understanding this technique. In this paper, thermal characteristics and kinetic and thermodynamic analysis during the co-pyrolysis of mushroom residue (MR) with pine sawdust (PS) or wheat straw (WS) were investigated in a TGA. The carbon structure and surface textures of co-pyrolytic char were explored using Raman spectroscopy and a scanning electron microscope. As the PS or WS mass ratio increased, the devolatilization index increased obviously, indicating that volatile release was promoted and concentrated. Weak interactions were observed between 250 and 400 °C during the co-pyrolysis process, which primarily affected the mass transfer, resulting in a change in the thermal decomposition temperatures and rates. The interactions had no prominent influence on the volatiles’ yields. The non-additive performance of average activation energies for the blends was observed due to the interactions, and the lowest average activation energy was obtained when the PS or WS mass ratio was 50%. The lower average pre-exponential factor of the blends indicated the reduced complicacy of the pyrolysis reaction. The relatively small deviation between the activation energy and enthalpy change (4.94–5.18 kJ·mol−1) signified the energy sensitivity of product formation. PS promoted the formation of small aromatic rings (<6 fused rings) in co-pyrolytic chars, whereas WS favored the production of larger rings (≥6 fused rings). The surface textures of the co-pyrolytic chars became porous, and the greater fractal dimensions of the surface morphology for the co-pyrolytic chars indicated that the char surface became irregular and rough.

Ecological compensation for protecting of river ecological flow (e-flow) is crucial to maintaining the health of river ecosystems; however, determining the fund sharing for ecological compensation can be challenging. To fill this scientific gap, we herein developed a specific framework to determine the fund-sharing of ecological compensation subjects. Such a framework mainly consists of three parts:1) Identifying the subjects who benefit from the consumption and eco-products provided by e-flow protection, and determining the sharing coefficient of the compensation subjects based on the ratio of their economic benefit to the total economic benefit; 2) Evaluating the ecological compensation resulting from the e-flow protection with the help of the production function method; 3) Combining the ecological compensation and compensation sharing coefficient to determine the fund sharing of compensation subjects. We have successfully applied this approach to the Baoji Section of the Weihe River and the Baojixia Yuanshang Irrigation District (BYID). The obtained results revealed that the compensation subjects were Baoji and Xianyang City, and their corresponding fund-sharing coefficients in 2010 in order were 0.71 and 0.29. It was predicted that ecological compensation for e-flow protection would be 209 million yuan in 2010 year, and the corresponding values of capital sharing are 148 million and 61 million yuan. Over the last 23 years (in the time interval of 2000-2022), the share of compensation funds has gradually decreased, indicating an increasing trend with the improvement of the security level. Join us in our mission to protect river ecosystems and maintain a healthy balance by using this approach for ecological compensation.

The Ni/Co/Mn ternary catalysts were fabricated through a one-step calcination process using the cathode material (CM) derived from spent lithium-ion batteries. The morphological and structural properties of the Ni/Co/Mn catalysts calcined at various temperatures (labeled as CM-450, CM-550 and CM-650) were characterized. CM-650 demonstrated the lowest concentration of metal leaching, excellent stability, and efficient activation performance for peroxymonosulfate (PMS) in the degradation of iopamidol (IPM). The catalytic activity of ternary CM-650 was obvious higher than the respective cathode material. Radical quenching experiments, electron paramagnetic resonance (EPR), and electrochemical characterization analysis indicated that both radical (·OH, SO4•−, ·O2−) and non-radical pathways (1O2, electron transfer) were involved in the CM-650/PMS system. The conversion between Ni(III)/Ni(II) and Co(III) /Co(II) as well as Mn(III)/Mn(II), Mn(IV)/Mn(III) redox couples on the surface of CM-650 facilitated the activation of PMS and a synergistic effect among Ni, Co and Mn existed. Liquid chromatography-mass spectrometry (LC-MS) and density functional theory (DFT) calculations were employed to analyze the degradation intermediates and reaction pathways of IPM. ECOSAR analysis indicated that some intermediates posed certain ecological risks. In summary, the one-step calcination of Ni/Co/Mn ternary catalysts exhibited a sustainable, cost-effective, and environmentally friendly approach for converting waste materials into valuable, high activating-performance materials.

Improving the protection level of river ecological flow (e-flow) can disrupt the balance of interests among various stakeholders in a region, potentially slowing down the protection process. To mitigate these negative impacts, we introduce a conceptual decision-making framework for modeling river e-flow, based on a dynamic equilibrium between the supply and demand of stakeholders. In this model, the willingness to pay for river e-flow protection is defined as the compensation supply from beneficiaries, while agricultural economic losses represent the compensation demand from affected parties. Illustrated with the Linjiacun section of the Baoji segment of the Weihe River (BSWHR), the main conclusions are as follows: (1) A conceptual decision-making framework for modeling the river e-flow is proposed, and deemed reasonable and feasible through rational analysis; (2) The e-flow of rivers in a typical dry year was 6.64 m3/s, and it increased with the increasing runoff; (3) The impact of changes in living standards and runoff on the e-flow in rivers was revealed, leading to the proposal of two policies for e-flow management; (4) This paper qualitatively analyzed the contrasts and relationships between the newly proposed model and mainstream methods (detailed in introduction), discussing the advantages, applicability, and prospect of this decision-making model. This model can provide an important theoretical and technical basis for the optimal management of water resources.

A biochar-supported Ni0/Co0/MnO composite catalyst was prepared from the cathode material (CM) of spent ternary 523 lithium-ion batteries (LIBs) and buckwheat hulls. The effect of pyrolysis temperature (x) and different loading ratios (y) of xBCyCM on the activation of peroxymonosulfate (PMS) was investigated. The results showed that the loading of Ni0/Co0/MnO on the biochar (BC) enhanced the IPM degradation and effectively reduced metal ions' leaching. The 850BC10CM/PMS system degraded iopamidol (IPM) within the wide pH range of 5.0-10.0. The pseudo-first reaction rate constant kobs was 0.0944 min- 1 during 25 min under optimal conditions (catalyst dose of 0.1 g center dot L- 1, 0.5 mM of PMS, and an initial pH value of 10.0), while the leaching concentrations of Ni, Co, and Mn were 0.089, 0.035, and 0.067 mg center dot L-1, respectively. Furthermore, the 850BC10CM degraded IPM by radicals (center dot OH, SO4 center dot- , and center dot O2- ) and non-radical pathways (1O2 and an electron transfer). As the pH value increased from 7.0 to 10.0, the fluorescence analysis and quenching experiments revealed a decrease in the effects of SO4 center dot-and center dot OH, while the effect of 1O2 was enhanced. The 850BC10CM could still achieve a removal rate of 86.6 % for IPM after four cycles. Based on the liquid chromatography-mass spectrometry (LC-MS) results of degradation intermediates, five possible degradation pathways were proposed. The 850BC10CM inhibited the formation of the iodoform CHI3. In short, the 850BC10CM, which was prepared by using a green, sustainable development of waste utilization, exhibited a safe and effective performance for the removal of emerging IPM pollutants.

The enhanced bioretention system provides a new way to solve the problems of stormwater management brought by urbanization. The knowledge on effects of media modification and long-term operation is scattered, so clogging interaction function, clogging time and depth are analysed to uncover the underneath. River sand, loess, and compost were used as basic fillers, and air-dried water treatment residual (WTR) and recycled aggregate from construction waste (RACW) were used as modifiers to formulate mixed fillers, and synchronized observation of the change rule of hydraulic conductivity and porosity of vertical layering. The study found that the infiltration coefficient of each system tended to decay gradually from top to bottom as the influent TSS accumulated. A set of improved media clogging process prediction framework has been proposed, using rainfall conditions in Northwest China as input conditions, the system clogging time is about 5.5 similar to 7.1 years and the depth of replacement is about 35 cm based on the principles of cake filtration and deep filtration. The results can further understand the function variation of bioretention system under TSS impact conditions, which is helpful to the prediction of the operating life of the system and the evaluation of media replacement depth.

The riparian ecosystem is highly susceptible to pollution, particularly heavy metals (HMs), due to its unique spatial position and landscape characteristics. Therefore, assessing the risks of HM pollution and identifying potential sources are crucial for formulating effective prevention and control measures. This study investigates the characteristics of HMs (Ni, Cr, Zn, Cd, Cu, Pb) pollution in the Weihe River riparian zone, identifies their sources, and assesses the associated ecological and human health risks. The results indicate that Ni, Zn, and Cd are the primary pollutants in riparian soil, with the average Cd concentration being 5.64 times higher than the background value, indicating a high potential ecological risk. Spatially, the average HM concentrations in the middle and upper reaches are higher than in the lower reaches. Vertically, as the distance from the riparian increases, the HM content exhibits a “U”-shaped pattern (increase-decrease-increase). The Absolute principal components multiple regression (APCS-MLR) receptor model identified four potential pollution sources: traffic sources; agricultural sources; industrial sources; and natural sources. Additionally, the Monte Carlo simulation-based human health risk assessment indicates that the non-carcinogenic health risk indices for all HMs are within acceptable ranges. For carcinogenic health risk indices, there is a 1.14% probability for children. However, the vast majority of the risks fall within acceptable or no-risk categories.

Maintaining the integrity of ecosystem service functions of rivers has become the top issue in the water shortage area of Northwest China. By combining the coupling relationship of sediment, water quality, and biodiversity and the hydraulic relationship of the section, we established a quantitative calculation method for the river ecological base flow, which is mainly divided into the following three steps: first, we determined the reasonable ecological flow velocity range of rivers via water purification, maintaining the river geometry and biodiversity; second, we combined the hydraulic relationship between the river ecological velocity range and the river ecological base flow to determine the protection target of the river ecological base flow; finally, we combined the remaining water volume of rivers and ecological base flow protection target of rivers to determine their protection rate. Take the Baoji section of the Weihe River as an example: the results show that the ecological base flow in the Baoji section of the Weihe River is [6.26, 9.17 m3/s] and [32.94, 38.93 m3/s] from October of this year to May of next year and from June to September, respectively, and the protection rates of the ecological base flow for five typical years are 62.47%, 41.10%, 16.16%, 15.07%, and 10.68%. These coupling methods can also be used in the world’s river basin, which has similar problems.

High-content solid waste (HCSWs) contains numerous polysaccharides and is widely recognized as an energy-generating substance. However, detailed studies on the use of HCSWs as substrates in microbial fuel cells (MFCs) to generate electricity and remove heavy metals from wastewater are scarce. In this study, the effects of shrimp shell (SS) and sodium acetate (SA), which are complex and simple substrates, respectively, as anodic carbon sources on the electricity generation performance of dual-chamber MFCs and the removal of Cu at the cathode were investigated. The structural characteristics of the anodic microbial communities of the MFCs were analyzed in terms of substrate type and concentration. The results demonstrated that the maximum voltage (206 mV) and maximum power density (28.82 mW/m2) of the MFC-SA were higher than those of the MFC-SS groups. The operating time and maximum power density increased with increasing SS concentration, and the maximum power density reached 24.75 mW/m2 at an SS concentration of 16 g/L. The Cu2+ ions in the catholyte were primarily reduced to elemental Cu and small amounts of Cu2O or CuO. The higher the concentration of SS, the higher the Cu removal rate, the greater the total amount of Cu removed, and the higher the MFC removal capacity. Pseudomonas was the only electroactive microorganism in the raw sludge, whereas Geobacter, Corynebacterium, Clostridium, Desulfovibrio, and Desulfosporosinus were detected in the MFCs at the end of the experiment. The relative abundance of the electroactive microorganisms increased from 19.4% to 36.0% as the SS concentration increased from 2 to 16 g/L. These results suggest that SS can be used as substrate for HCSW degradation to provide the energy required for heavy-metal reduction.

In the world, non-point source (NPS) has become one of the important factors affecting the water environment and water ecological security in the basin. In this paper, we investigate the response of runoff to pollution loads by establishing the MIKE SHE and MIKE HYDRO River coupled model with the Danjiang river basin as the research object; The MIKE LOAD is used to analyze the spatial and temporal distribution characteristics of agricultural NPS pollution and to perform equivalence load analysis of pollutants in the basin; Single and combined control measures are set up to simulate the reduction effect of each pollutant for NPS pollution control in the basin. The results show that daily runoff has a high correlation with daily pollution loads of ammonia nitrogen (NH3-N) and total phosphorous (TP); The pollution load of Jingziguan section calculated by the coupled model is comparable with the results calculated by MIKE LOAD, and the relative error is below 30%, and the simulation results are reasonable. The trend of the load into the river for all pollutants is consistent with the rainfall and generally shows the characteristics of high loads in flood season and low loads in non-flood season. The total emissions of NPS pollutants in the basin are TN>NH3-N>TP>COD, and the loads share of the four pollutants are 52.82%, 21.31%, 19.42% and 6.44% respectively. Four single and one combination measures are set up to evaluate the pollutant reduction effects. The reduction effect of combined measures is significantly better than that of single measures.