摘要：
The residual sludge generated from steel wastewater treatment is abundant in iron resource and its recycling has attracted widespread attention. In this study, a novel iron-rich biochar (FSB) with acceptable environmental risk was developed by one-step pyrolysis using steel sludge as raw material, and its adsorption-reduction efficiency and column experiments for hexavalent chromium [Cr(VI)] were determined. The results showed that pyrolysis can effectively reduce the potential environmental risk of iron-rich sludge and effectively enrich iron resources in the biochar matrix. The heavy metal accumulation pattern, potential environmental risk and Cr(VI) adsorption-reduction performance of FSB were affected by pyrolysis temperature, and the optimal performance was achieved at a pyrolysis temperature of 500℃, and the maximum adsorption capacity of FSB pyrolyzed at 500℃ (FSB500) could be as high as 200 mg g −1 . The apparent model fitting showed that Cr(VI) removal by FSB500 was an adsorption-reduction-adsorption process as follows: (i) Cr(VI) was attracted onto FSB500 by electrostatic force; (ii) the oxygen-containing functional groups, persistent free radicals, and endogenous iron on the FSB500 surface acted as the electron donors to convert Cr(VI) to Cr(III); (iii) the released Cr(III) complexed on the FSB500 surface again. In the column experiment, FSB500 showed a high removal capacity of 55.94 mg g −1 under specific conditions. Thus, this study suggests that iron-rich sludge can be prepared into biochar for resource utilization and can be used as an effective alternative for Cr(VI) wastewater treatment.
The residual sludge generated from steel wastewater treatment is abundant in iron resource and its recycling has attracted widespread attention. In this study, a novel iron-rich biochar (FSB) with acceptable environmental risk was developed by one-step pyrolysis using steel sludge as raw material, and its adsorption-reduction efficiency and column experiments for hexavalent chromium [Cr(VI)] were determined. The results showed that pyrolysis can effectively reduce the potential environmental risk of iron-rich sludge and effectively enrich iron resources in the biochar matrix. The heavy metal accumulation pattern, potential environmental risk and Cr(VI) adsorption-reduction performance of FSB were affected by pyrolysis temperature, and the optimal performance was achieved at a pyrolysis temperature of 500℃, and the maximum adsorption capacity of FSB pyrolyzed at 500℃ (FSB500) could be as high as 200 mg g −1 . The apparent model fitting showed that Cr(VI) removal by FSB500 was an adsorption-reduction-adsorption process as follows: (i) Cr(VI) was attracted onto FSB500 by electrostatic force; (ii) the oxygen-containing functional groups, persistent free radicals, and endogenous iron on the FSB500 surface acted as the electron donors to convert Cr(VI) to Cr(III); (iii) the released Cr(III) complexed on the FSB500 surface again. In the column experiment, FSB500 showed a high removal capacity of 55.94 mg g −1 under specific conditions. Thus, this study suggests that iron-rich sludge can be prepared into biochar for resource utilization and can be used as an effective alternative for Cr(VI) wastewater treatment.
作者机构：
[Wu, Zhiyuan; Meng, Wenkang; Meng, WK] Changsha Univ Sci & Technol, Sch Hydraul & Ocean Engn, Changsha 410114, Peoples R China.;[Wu, Zhiyuan; Meng, Wenkang; Meng, WK] Key Lab Dongting Lake Aquat Ecoenvironm Control &, Changsha 410114, Peoples R China.;[Wu, Zhiyuan; Meng, Wenkang; Meng, WK] Key Lab Water Sediment Sci & Water Disaster Preven, Changsha 410114, Peoples R China.;[Li, Jia; Yu, Ching-hao; An, RD; Meng, Wenkang; An, Ruidong; Meng, WK] Sichuan Univ, Coll Water Resource & Hydropower, State Key Lab Hydraul & Mt River Engn, Chengdu 610065, Peoples R China.
通讯机构：
[An, RD ; Meng, WK] S;[Meng, WK ] C;Changsha Univ Sci & Technol, Sch Hydraul & Ocean Engn, Changsha 410114, Peoples R China.;Key Lab Dongting Lake Aquat Ecoenvironm Control &, Changsha 410114, Peoples R China.;Key Lab Water Sediment Sci & Water Disaster Preven, Changsha 410114, Peoples R China.
关键词：
Two-phase flow;Level set;Volume of fluid;WENO;Finite volume method
摘要：
The modeling of interfacial two-phase flows involves various fields such as hydraulic engineering, marine engineering, chemical industry, etc., whose difficulty lies in the accurate simulation of the two-phase flow interface. This paper presents a VOF(volume of fluid)-based LS (level set) method with WENO (weighted essentially non-oscillatory) scheme in the finite volume method. The proposed method initializes the LS function by transforming the VOF function, which does not have the characteristics of the distance function yet. Therefore, the next step is to re-distance the transformed LS function by solving the re-initialization equation. For solving the re-initialization equation, the WENO scheme in the finite volume method is employed, providing fifth-order accuracy for the convection term. To validate the proposed VOF-based LS method combined with the WENO scheme, five test cases are presented, including Zalesak's disk, vortex deformation, Rayleigh-Taylor instability, two-dimensional bubble rise, and dam break flow. The numerical results from these interfacial two-phase flow cases demonstrate that the VOF-based LS method with the WENO scheme in the finite volume method can achieve accurate capture of the interface while maintaining excellent mass conservation characteristics.
The modeling of interfacial two-phase flows involves various fields such as hydraulic engineering, marine engineering, chemical industry, etc., whose difficulty lies in the accurate simulation of the two-phase flow interface. This paper presents a VOF(volume of fluid)-based LS (level set) method with WENO (weighted essentially non-oscillatory) scheme in the finite volume method. The proposed method initializes the LS function by transforming the VOF function, which does not have the characteristics of the distance function yet. Therefore, the next step is to re-distance the transformed LS function by solving the re-initialization equation. For solving the re-initialization equation, the WENO scheme in the finite volume method is employed, providing fifth-order accuracy for the convection term. To validate the proposed VOF-based LS method combined with the WENO scheme, five test cases are presented, including Zalesak's disk, vortex deformation, Rayleigh-Taylor instability, two-dimensional bubble rise, and dam break flow. The numerical results from these interfacial two-phase flow cases demonstrate that the VOF-based LS method with the WENO scheme in the finite volume method can achieve accurate capture of the interface while maintaining excellent mass conservation characteristics.
摘要：
In the single-stage partial nitritation-anammox process for high-ammonium wastewater treatment, the presence of sufficient biomass with high activity is essential. This study developed an innovative airlift inner-circulation partition bioreactor (AIPBR) with a dual-cylinder structure. During the 362 days’ operation, the AIPBR exhibited robust and stable nitrogen removal performance under diverse influent ammonium spanning from 300 to 1800 mg N/L. Notably, when the influent ammonium was 1820 ± 34 mg N/L, the nitrogen removal rate reached 3.194 ± 0.074 kg N/m³/d, accompanied by removal efficiency of 87.6 ± 1.5%. The unique design of the reactor enabled the formation of dissolved oxygen gradient, which improved the synergy of functional microorganisms by facilitating mass transfer within the sludge. Additionally, it maintained appropriate hydraulic shear in the inner cylinder to support granule formation and simultaneously reduced excessive flow in the outer cylinder to prevent sludge loss. Through the cyclic granulation, the system fostered a symbiotic consortium of flocculent and granular sludge with particle size predominantly distributed within the range of 200–400 μm, which enhanced the activity of microorganisms. These findings highlight the potential of AIPBR as a novel and effective strategy for high-ammonium wastewater treatment.
In the single-stage partial nitritation-anammox process for high-ammonium wastewater treatment, the presence of sufficient biomass with high activity is essential. This study developed an innovative airlift inner-circulation partition bioreactor (AIPBR) with a dual-cylinder structure. During the 362 days’ operation, the AIPBR exhibited robust and stable nitrogen removal performance under diverse influent ammonium spanning from 300 to 1800 mg N/L. Notably, when the influent ammonium was 1820 ± 34 mg N/L, the nitrogen removal rate reached 3.194 ± 0.074 kg N/m³/d, accompanied by removal efficiency of 87.6 ± 1.5%. The unique design of the reactor enabled the formation of dissolved oxygen gradient, which improved the synergy of functional microorganisms by facilitating mass transfer within the sludge. Additionally, it maintained appropriate hydraulic shear in the inner cylinder to support granule formation and simultaneously reduced excessive flow in the outer cylinder to prevent sludge loss. Through the cyclic granulation, the system fostered a symbiotic consortium of flocculent and granular sludge with particle size predominantly distributed within the range of 200–400 μm, which enhanced the activity of microorganisms. These findings highlight the potential of AIPBR as a novel and effective strategy for high-ammonium wastewater treatment.
摘要：
The stepped paddy fields (SPFs) are important for food security and sustainable development. The unique spatial structure and complex hydrological processes in this system make it difficult to understand the migration of pollutants. In this study, microplastic pollution was investigated in the water and soil from Ziquejie SPFs, China. Samples were taken according to different stages of rice cultivation, different altitudes, and soil depths. Before rice planting, the average abundance in the water and soil samples was 1.3 ± 1.1 items/L and 292.2 ± 260.8 items/kg, respectively. After rice harvesting, the average abundance in soil increased to 495.37 ± 175.46 items/kg. More microplastics were found in depths of 0–15 cm than that of 15–30 cm, but the difference was not significant. Major microplastics were small (<1 mm) polyethylene (PE) and polypropylene (PP) fibers, with the main color of blue and transparent. The study found that SPFs hindered the migration of microplastics in irrigation water and hydraulic conditions affected the accumulation of microplastics. The edge areas in paddy fields where the water flowed slowly and were prone to vortices made it easier for microplastics to stay. Most of the microplastics accumulated in the upper SPF. After rice harvesting, the overall abundance of microplastics in the SPFs increased. Fibers and fragments exhibited different characteristics in migration. This study attempts to draw attention to the ecological risks caused by microplastic pollution in SPFs, especially in the upper paddy field and the effluent. The results are helpful for the protection of the SPF ecosystem and provide valuable references for future research.
The stepped paddy fields (SPFs) are important for food security and sustainable development. The unique spatial structure and complex hydrological processes in this system make it difficult to understand the migration of pollutants. In this study, microplastic pollution was investigated in the water and soil from Ziquejie SPFs, China. Samples were taken according to different stages of rice cultivation, different altitudes, and soil depths. Before rice planting, the average abundance in the water and soil samples was 1.3 ± 1.1 items/L and 292.2 ± 260.8 items/kg, respectively. After rice harvesting, the average abundance in soil increased to 495.37 ± 175.46 items/kg. More microplastics were found in depths of 0–15 cm than that of 15–30 cm, but the difference was not significant. Major microplastics were small (<1 mm) polyethylene (PE) and polypropylene (PP) fibers, with the main color of blue and transparent. The study found that SPFs hindered the migration of microplastics in irrigation water and hydraulic conditions affected the accumulation of microplastics. The edge areas in paddy fields where the water flowed slowly and were prone to vortices made it easier for microplastics to stay. Most of the microplastics accumulated in the upper SPF. After rice harvesting, the overall abundance of microplastics in the SPFs increased. Fibers and fragments exhibited different characteristics in migration. This study attempts to draw attention to the ecological risks caused by microplastic pollution in SPFs, especially in the upper paddy field and the effluent. The results are helpful for the protection of the SPF ecosystem and provide valuable references for future research.
作者：
Yang, Shuanglin;Deng, Yiyi;Jiang, Jingyi;Kong, Zhe;Ali, Elsayed A. E.;...
期刊：
Journal of Water Process Engineering,2025年71:107201 ISSN：2214-7144
通讯作者：
Chen, H
作者机构：
[Xu, Ronghua; Chen, Hong; Chen, H; Deng, Yiyi; Yang, Shuanglin; Jiang, Jingyi] Changsha Univ Sci & Technol, Sch Hydraul & Environm Engn, Key Lab Water Sediment Sci & Water Disaster Preven, Changsha 410114, Peoples R China.;[Kong, Zhe] Suzhou Univ Sci & Technol, Sch Environm Sci & Engn, Suzhou Natl Joint Lab Green & Low Carbon Wastewate, Suzhou 215009, Peoples R China.;[Ali, Elsayed A. E.] Agr Engn Res Inst AEnRI, Agr Res Ctr ARC, POB 256, Giza, Egypt.;[Deng, Zhengyu] China Machinery Int Engn Design & Res Inst Co Ltd, Changsha 410007, Peoples R China.;[Jiang, Wang] Hunan Prov Architectural Design Inst Grp Co Ltd, Changsha 410208, Peoples R China.
通讯机构：
[Chen, H ] C;Changsha Univ Sci & Technol, Sch Hydraul & Environm Engn, Key Lab Water Sediment Sci & Water Disaster Preven, Changsha 410114, Peoples R China.
关键词：
Sponge cities;Runoff pollution;Bioretention facilities;Soil environmental factors;Microbial community structure
摘要：
To investigate the long-term removal mechanisms of field-scale bioretention facilities using different media for roof runoff treatment, volcanic rock-based (VBF) and zeolite-based bioretention facilities (ZBF) were constructed, and their pollutant removal, soil characteristics, and microbial community dynamics were monitored. It was shown that VBF exhibited higher removal rates for chemical oxygen demand (COD, 84.9 %), ammonia nitrogen (NH 4 + –N, 82.3 %), and total phosphorus (TP, 65.6 %), which can be ascribed to the larger specific surface area and higher iron‑aluminum oxide contents of volcanic rocks. In contrast, ZBF demonstrated superior NO 3 − –N removal efficiency (60.3 %). However, the accumulation of total organic carbon, NH 4 + –N, NO 3 − –N, and TP in VBF was 1.04–1.16 times higher than in ZBF, and redundancy analysis revealed that functional bacteria in VBF were more sensitive to the changes of soil environmental factors (e.g., pH, NH 4 + –N and TP). Furthermore, long-term pollutant inputs resulted in a higher abundance of bacteria involved in organic matter degradation and phosphate solubilization ( Gaiellales , A4b , Vicinamibacteraceae , etc.) in VBF, while ZBF contained a higher abundance of nitrifying and denitrifying bacteria ( Arthrobacter , Roseiflexaceae , KD4-96 , Hyphomicrobium , etc.). These microbial differences contributed to the varying pollutant removal performances between the two facilities, especially for NH 4 + -N and NO 3 − -N. This study provides valuable insights into the long-term pollution control performance and potential media modifications for assembled bioretention facilities.
To investigate the long-term removal mechanisms of field-scale bioretention facilities using different media for roof runoff treatment, volcanic rock-based (VBF) and zeolite-based bioretention facilities (ZBF) were constructed, and their pollutant removal, soil characteristics, and microbial community dynamics were monitored. It was shown that VBF exhibited higher removal rates for chemical oxygen demand (COD, 84.9 %), ammonia nitrogen (NH 4 + –N, 82.3 %), and total phosphorus (TP, 65.6 %), which can be ascribed to the larger specific surface area and higher iron‑aluminum oxide contents of volcanic rocks. In contrast, ZBF demonstrated superior NO 3 − –N removal efficiency (60.3 %). However, the accumulation of total organic carbon, NH 4 + –N, NO 3 − –N, and TP in VBF was 1.04–1.16 times higher than in ZBF, and redundancy analysis revealed that functional bacteria in VBF were more sensitive to the changes of soil environmental factors (e.g., pH, NH 4 + –N and TP). Furthermore, long-term pollutant inputs resulted in a higher abundance of bacteria involved in organic matter degradation and phosphate solubilization ( Gaiellales , A4b , Vicinamibacteraceae , etc.) in VBF, while ZBF contained a higher abundance of nitrifying and denitrifying bacteria ( Arthrobacter , Roseiflexaceae , KD4-96 , Hyphomicrobium , etc.). These microbial differences contributed to the varying pollutant removal performances between the two facilities, especially for NH 4 + -N and NO 3 − -N. This study provides valuable insights into the long-term pollution control performance and potential media modifications for assembled bioretention facilities.
摘要：
Geopolymer concrete is a potential partial substitute for Portland cement (PC) concrete in civil engineering. Understanding chloride-binding behavior and mechanisms in geopolymers is essential for evaluating durability of geopolymer concrete in chloride-rich environments. This study investigated the chloride-binding behavior of metakaolin (MK) geopolymers by examining the influence of chloride ion concentrations, alkali activator concentrations, and pore solution pH levels on their chloride-binding capacities. The correlation between the bound chloride ion content and the geopolymerization degree of MK was analyzed. The experimental results indicated that the binding of MK geopolymer to chloride ions is physical adsorption under the competition of hydroxide ions. Thus when the pH of pore solution decreases from 11.69 to 10.55, the amount of bound chloride increases by 1.95 times. The chloride-binding capacity of the MK geopolymer was primarily determined by the N-A-S-H gel content and the pH of pore solution. Under the same pH levels and chloride ion concentration, the chloride ion content bound per unit N-A-S-H gel remained constant, independent of N-A-S-H gel content. Based on these findings, a new method was proposed to evaluate the geopolymerization degree of MK by mearsuring the chloride-binding capacity of the N-A-S-H gel. The proposed method shows a small margin of error (<5 %) compared to selective acid dissolution analysis, providing valuable insights for research into geopolymer precursor reactions.
Geopolymer concrete is a potential partial substitute for Portland cement (PC) concrete in civil engineering. Understanding chloride-binding behavior and mechanisms in geopolymers is essential for evaluating durability of geopolymer concrete in chloride-rich environments. This study investigated the chloride-binding behavior of metakaolin (MK) geopolymers by examining the influence of chloride ion concentrations, alkali activator concentrations, and pore solution pH levels on their chloride-binding capacities. The correlation between the bound chloride ion content and the geopolymerization degree of MK was analyzed. The experimental results indicated that the binding of MK geopolymer to chloride ions is physical adsorption under the competition of hydroxide ions. Thus when the pH of pore solution decreases from 11.69 to 10.55, the amount of bound chloride increases by 1.95 times. The chloride-binding capacity of the MK geopolymer was primarily determined by the N-A-S-H gel content and the pH of pore solution. Under the same pH levels and chloride ion concentration, the chloride ion content bound per unit N-A-S-H gel remained constant, independent of N-A-S-H gel content. Based on these findings, a new method was proposed to evaluate the geopolymerization degree of MK by mearsuring the chloride-binding capacity of the N-A-S-H gel. The proposed method shows a small margin of error (<5 %) compared to selective acid dissolution analysis, providing valuable insights for research into geopolymer precursor reactions.
作者机构：
[Chen, Long; Yao, Yu; Sun, Zhenkai; Wang, Hao] Changsha Univ Sci & Technol, Sch Hydraul & Ocean Engn, Changsha 410114, Hunan, Peoples R China.;[Yao, Yu; Chen, Long] Key Lab Water Sediment Sci & Water Disaster Preven, Changsha 410114, Hunan, Peoples R China.;[Chen, Long] Res Inst Innovat Dev Transportat & Energy Integrat, Changsha 410114, Hunan, Peoples R China.;[Chin, Ren-Jie] Univ Tunku Abdul Rahman, Lee Kong Chian Fac Engn & Sci, Dept Civil Engn, Kajang 43000, Malaysia.
通讯机构：
[Chen, L ] C;Changsha Univ Sci & Technol, Sch Hydraul & Ocean Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Power fluctuation;Tidal turbine fatigue;Seabed bathymetry;Blockage ratio;Wake flow
摘要：
The combination of waves, currents, and seabed bathymetry can result in large hydrodynamic loads that can lead to excessive loading, tidal turbine fatigue and power fluctuations. In this work, a 1:50 scaled tidal stream turbine model is utilized to further the fundamental understanding of tidal turbine behavior with present of seabed bathymetry. The influence of seabed bathymetry proximity on tidal turbines power and loading fluctuations are assessed in terms of spectral density. In the spectral domain of power coefficient, the presence of seabed bathymetry effectively reduces the energy cascade. For thrust coefficient, the frequency decay depicted peaks nearly at the harmonics along the rotor's rotational ( fr ). The coupled effects of seabed bathymetry and blockage ratio were also examined by a transient numerical analysis. The implication of blockage effects is not only to increase the hydrodynamic performance but also shifting the optimum performance TSR to a higher value. The presence of seabed bathymetry resulted in skewed wake flows and the seabed element obstruction is the primary mechanism for reduced performance at close proximity. The results of this study provide recommendations for turbine positioning and fatigue analysis in such flows.
The combination of waves, currents, and seabed bathymetry can result in large hydrodynamic loads that can lead to excessive loading, tidal turbine fatigue and power fluctuations. In this work, a 1:50 scaled tidal stream turbine model is utilized to further the fundamental understanding of tidal turbine behavior with present of seabed bathymetry. The influence of seabed bathymetry proximity on tidal turbines power and loading fluctuations are assessed in terms of spectral density. In the spectral domain of power coefficient, the presence of seabed bathymetry effectively reduces the energy cascade. For thrust coefficient, the frequency decay depicted peaks nearly at the harmonics along the rotor's rotational ( fr ). The coupled effects of seabed bathymetry and blockage ratio were also examined by a transient numerical analysis. The implication of blockage effects is not only to increase the hydrodynamic performance but also shifting the optimum performance TSR to a higher value. The presence of seabed bathymetry resulted in skewed wake flows and the seabed element obstruction is the primary mechanism for reduced performance at close proximity. The results of this study provide recommendations for turbine positioning and fatigue analysis in such flows.
摘要：
While carbonate sediment transport processes over coral reefs have been extensively investigated in the past decade，very few studies have focused on the morphodynamic response of sandy reef flats to wave action. In this study, a set of innovative wave-flume laboratory experiments was conducted for the first time to investigate the evolution of reef flat based on a barrier reef profile. Various monochromatic wave conditions (incident wave height, incident wave period and initial reef-flat water level) and sediment layer thicknesses were tested. A sand layer was paved on the reef flat to simulate a moveable bed and the reef surface roughness was replicated using an array of cylinders. Subsequently, a phase-resolving non-hydrostatic model (XBeach-NH) was adopted to simulate both the hydrodynamic and morphodynamic processes in the reef environment. A vegetation module was incorporated into Xbeach-NH to represent the rough reef surface. The adopted model was validated against the laboratory dataset for the first time as reported in this study. It was then used to examine the impacts of varying fore-reef slopes, sediment grain sizes and reef surface roughness on the morphodynamic response of sandy reef flats to monochromatic wave action. Model outputs suggested that projected sea-level rise, reduced reef surface roughness and increased storminess due to climate change have profound impacts on the morphodynamic processes on the reef flat thus may eventually contribute the geomorphological sustainability of reef islands.
While carbonate sediment transport processes over coral reefs have been extensively investigated in the past decade，very few studies have focused on the morphodynamic response of sandy reef flats to wave action. In this study, a set of innovative wave-flume laboratory experiments was conducted for the first time to investigate the evolution of reef flat based on a barrier reef profile. Various monochromatic wave conditions (incident wave height, incident wave period and initial reef-flat water level) and sediment layer thicknesses were tested. A sand layer was paved on the reef flat to simulate a moveable bed and the reef surface roughness was replicated using an array of cylinders. Subsequently, a phase-resolving non-hydrostatic model (XBeach-NH) was adopted to simulate both the hydrodynamic and morphodynamic processes in the reef environment. A vegetation module was incorporated into Xbeach-NH to represent the rough reef surface. The adopted model was validated against the laboratory dataset for the first time as reported in this study. It was then used to examine the impacts of varying fore-reef slopes, sediment grain sizes and reef surface roughness on the morphodynamic response of sandy reef flats to monochromatic wave action. Model outputs suggested that projected sea-level rise, reduced reef surface roughness and increased storminess due to climate change have profound impacts on the morphodynamic processes on the reef flat thus may eventually contribute the geomorphological sustainability of reef islands.
作者：
Yi Li;Ping Xue;Yaning Liu;Jingrui Wang*;Wenjie Yin
期刊：
Energy,2025年:135592 ISSN：0360-5442
通讯作者：
Jingrui Wang
作者机构：
[Ping Xue] School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, China;Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, Wuhan, 430068, China;[Yi Li] School of Hydraulic Engineering, Changsha University of Science and Technology, Changsha, 410114, China;[Yaning Liu] Department of Mathematical and Statistical Sciences, University of Colorado Denver, Denver, CO, 80204, USA;[Jingrui Wang] Technical Centre for Soil, Agriculture and Rural Ecology and Environment, Ministry of Ecology and Environment, Beijing, 100012, China
通讯机构：
[Jingrui Wang] T;Technical Centre for Soil, Agriculture and Rural Ecology and Environment, Ministry of Ecology and Environment, Beijing, 100012, China
摘要：
Compressed air energy storage in aquifers (CAESA) is a novel large-scale energy storage technology. However, the permeability effects on underground processes and responsive wellhead performance require further investigation. In this study, a coupled wellbore and aquifer model is developed based on the practical Dezhou CAESA test in flat aquifers. A novel index, the Pressure Fluctuation Index (PFI), is proposed to evaluate energy storage performance from the perspective of wellhead pressure fluctuations, alongside efficiency and gas recovery. It is found that the balance between effective air support loss due to diffusion and the aquifer’s inherent deliverability controls response performance at different permeability levels. The dominance between these two competing factors shifts as permeability increases. An optimal permeability of 100md is identified for achieving the best energy storage performance. With a cyclic rate increase, the performance shows the opposite trends in different permeability regions and the optimum permeability becomes larger. When considering the initial air bubble, better energy storage performance and a larger optimum permeability can be achieved with greater mass. In high-permeability regions, larger injection rates improve efficiency and gas recovery, while pressure fluctuations perform slightly worse in low-permeability regions. The findings provide valuable insights for site selection and engineering optimization.
Compressed air energy storage in aquifers (CAESA) is a novel large-scale energy storage technology. However, the permeability effects on underground processes and responsive wellhead performance require further investigation. In this study, a coupled wellbore and aquifer model is developed based on the practical Dezhou CAESA test in flat aquifers. A novel index, the Pressure Fluctuation Index (PFI), is proposed to evaluate energy storage performance from the perspective of wellhead pressure fluctuations, alongside efficiency and gas recovery. It is found that the balance between effective air support loss due to diffusion and the aquifer’s inherent deliverability controls response performance at different permeability levels. The dominance between these two competing factors shifts as permeability increases. An optimal permeability of 100md is identified for achieving the best energy storage performance. With a cyclic rate increase, the performance shows the opposite trends in different permeability regions and the optimum permeability becomes larger. When considering the initial air bubble, better energy storage performance and a larger optimum permeability can be achieved with greater mass. In high-permeability regions, larger injection rates improve efficiency and gas recovery, while pressure fluctuations perform slightly worse in low-permeability regions. The findings provide valuable insights for site selection and engineering optimization.
作者机构：
[Yuren Zeng] School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, Hunan, 410114, PR China;Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha, Hunan, 410114, PR China;[Yu Yao; Ting Zhou; Changbo Jiang] School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, Hunan, 410114, PR China<&wdkj&>Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha, Hunan, 410114, PR China
通讯机构：
[Ting Zhou] S;School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha, Hunan, 410114, PR China<&wdkj&>Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha, Hunan, 410114, PR China
摘要：
There has been significant interest in post-tsunami surveys regarding how effective fringing reefs are at protecting coastlines from inundation caused by tsunamis. Limited attention has been given to the wave transformation characteristics and wave run-up dynamics within a complex reef-lagoon-channel system compared to the extensively studied two-dimensional horizontal fringing reefs. In response to this research gap, a three-dimensional numerical wave tank has been created, incorporating the incompressible Reynolds-averaged Navier-Stokes equations accompanied with k-ω SST turbulence model. The volume of fluid (VOF) strategy is employed to track the free surface, accompanied by advanced grid cascading encryption technology. Laboratory measurements (Swigler, 2009; Briggs et al., 1995) of the waves are utilized for model validation. The influence of incident wave height, reef flat submergence, fore-reef slope, and channel width on wave propagation characteristics were examined. The results reveal that the relative run-up decreases with larger wave heights and decreases near channels as reef flat submergences rise. Initially, smaller channels reduce relative run-up, but it increases again with widening, shifting the maximum relative run-up location away from the channel, while fore-reef slope changes minimally affect run-up.
There has been significant interest in post-tsunami surveys regarding how effective fringing reefs are at protecting coastlines from inundation caused by tsunamis. Limited attention has been given to the wave transformation characteristics and wave run-up dynamics within a complex reef-lagoon-channel system compared to the extensively studied two-dimensional horizontal fringing reefs. In response to this research gap, a three-dimensional numerical wave tank has been created, incorporating the incompressible Reynolds-averaged Navier-Stokes equations accompanied with k-ω SST turbulence model. The volume of fluid (VOF) strategy is employed to track the free surface, accompanied by advanced grid cascading encryption technology. Laboratory measurements (Swigler, 2009; Briggs et al., 1995) of the waves are utilized for model validation. The influence of incident wave height, reef flat submergence, fore-reef slope, and channel width on wave propagation characteristics were examined. The results reveal that the relative run-up decreases with larger wave heights and decreases near channels as reef flat submergences rise. Initially, smaller channels reduce relative run-up, but it increases again with widening, shifting the maximum relative run-up location away from the channel, while fore-reef slope changes minimally affect run-up.
摘要：
This study employed the k – ω Shear StressTransport turbulence model and the Arbitrary Lagrangian–Eulerian dynamic mesh method in OpenFOAM to investigate the effects of the oscillation frequency ratio ( f r ) on flow characteristics around a square cylinder at Re = 2.2 × 10 4 . The results revealed that the time-averaged drag coefficient ( C d ¯ ) and the Root Mean Square (RMS) of the lift coefficient ( C l ′ ) reached the peak values when f r = 1.0. For f r ≥ 2.5, the time-averaged pressure coefficient ( C p ¯ ) on the leeward side of the square cylinder exhibited a distribution pattern characterized by higher values in the middle and lower values near the edges, while the RMS of the pressure coefficient ( C p ′ ) demonstrated the opposite trend. As f r increased, the secondary recirculation bubbles along the sidewalls of the square cylinder gradually diminished, while the primary recirculation bubbles in the wake and near the sidewalls shortened. Additionally, the RMS of the transverse velocity ( U y ′ ) exceeded that of the streamwise velocity ( U x ′ ) in the wake region. The energy transfer coefficient ( C E ) in the synchronous range was significantly lower than that in the non-synchronous range at different f r . It is worth noting that in the synchronous range, the energy transferred from the cylinder to the fluid attained its maximum value. The amplitude spectrum of the lift coefficient exhibited chaotic characteristics, containing exclusively odd-order superharmonics. With increasing f r , the vortex structures on both sides of the cylinder became increasingly fragmented, and the wake's vortex pattern transitioned from a single-row to a double-row structure. These findings provide a deeper theoretical understanding of turbulence and the flow-induced motion of structures.
期刊：
Journal of Hydrology,2025年:133026 ISSN：0022-1694
通讯作者：
Reza Ahmadian
作者机构：
School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha 410114, China;[Man Yue Lam; Reza Ahmadian] Hydro-Environmental Research Centre, School of Engineering, Cardiff University, Cardiff CF243AA, UK;[Junqiang Xia] State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China;Hunan University of Technology, Zhuzhou 412007, China;Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, China
通讯机构：
[Reza Ahmadian] H;Hydro-Environmental Research Centre, School of Engineering, Cardiff University, Cardiff CF243AA, UK
摘要：
Floods are one of the most destructive disasters and require a range of structural and non-structural measures to reduce their impacts. Evacuation is an effective non-structural measure to increase the resilience of flood-affected areas. This study aims to provide a systematic overview of evacuation planning for urban flood scenarios in terms of theories, methods, models, and techniques for both pedestrians and vehicles. The review addresses key components such as flood simulation modelling, flood hazard assessment methods, shelter identification, evacuation route development, and evacuee movement modelling. Among these, we highlight the comparison and analysis of flood hazard assessment methods, shelter optimisation and route optimisation. Additionally, a systematic analysis and comparison of evacuation shelters, evacuation route algorithms, and evacuee movement models are presented. Meta-heuristic algorithms have been shown to perform well for evacuation routes. Finally, the insights into four recent directions for enhancing evacuation plans include consideration of pedestrian and vehicle movement speeds, evacuee psychology, multimodal emergency evacuation, and the effect of overhead power lines on rescue operations.
Floods are one of the most destructive disasters and require a range of structural and non-structural measures to reduce their impacts. Evacuation is an effective non-structural measure to increase the resilience of flood-affected areas. This study aims to provide a systematic overview of evacuation planning for urban flood scenarios in terms of theories, methods, models, and techniques for both pedestrians and vehicles. The review addresses key components such as flood simulation modelling, flood hazard assessment methods, shelter identification, evacuation route development, and evacuee movement modelling. Among these, we highlight the comparison and analysis of flood hazard assessment methods, shelter optimisation and route optimisation. Additionally, a systematic analysis and comparison of evacuation shelters, evacuation route algorithms, and evacuee movement models are presented. Meta-heuristic algorithms have been shown to perform well for evacuation routes. Finally, the insights into four recent directions for enhancing evacuation plans include consideration of pedestrian and vehicle movement speeds, evacuee psychology, multimodal emergency evacuation, and the effect of overhead power lines on rescue operations.
摘要：
Radical- and nonradical-based advanced oxidation processes (AOPs) have been widely used as water cleaning technologies. It is a great challenge to achieve a synergy between these two methodologies for enhancing the performance of water purification. Here we report a novel strategy of permanganate (PM)-promoted photocatalytic oxidation by using TiO 2 with different ratios of (101) and (001) facets as model photocatalysts to achieve a synergy of nonradical-radical relay oxidation process. This approach can simultaneously trigger PM activation by photogenerated electrons and result in the selective deposition of Mn on TiO 2 (101) facet with the formation of single-atom Mn photocatalyst (Mn@TiO 2 ). Conversely, the formed Mn@TiO 2 photocatalyst has a remarkable photocatalytic activity with significantly enhanced radical generation ability due to the regulation of electronic structure of catalyst and the creation of interfacial electric field between Mn and O (TiO 2 ). This approach is highly efficient for the degradation of refractory organic pollutants with superior performances. Physical, theoretical and in situ spectroscopy investigations indicate the crucial role of PM, which is the source of nonradical and radical species, and is the key compound for preparing Mn@TiO 2 . This study provides new insights into the design of efficient single-atom (photo)catalyst, and offers a versatile AOPs for water purification.
Radical- and nonradical-based advanced oxidation processes (AOPs) have been widely used as water cleaning technologies. It is a great challenge to achieve a synergy between these two methodologies for enhancing the performance of water purification. Here we report a novel strategy of permanganate (PM)-promoted photocatalytic oxidation by using TiO 2 with different ratios of (101) and (001) facets as model photocatalysts to achieve a synergy of nonradical-radical relay oxidation process. This approach can simultaneously trigger PM activation by photogenerated electrons and result in the selective deposition of Mn on TiO 2 (101) facet with the formation of single-atom Mn photocatalyst (Mn@TiO 2 ). Conversely, the formed Mn@TiO 2 photocatalyst has a remarkable photocatalytic activity with significantly enhanced radical generation ability due to the regulation of electronic structure of catalyst and the creation of interfacial electric field between Mn and O (TiO 2 ). This approach is highly efficient for the degradation of refractory organic pollutants with superior performances. Physical, theoretical and in situ spectroscopy investigations indicate the crucial role of PM, which is the source of nonradical and radical species, and is the key compound for preparing Mn@TiO 2 . This study provides new insights into the design of efficient single-atom (photo)catalyst, and offers a versatile AOPs for water purification.
摘要：
The construction of steel-truss-girder cable-stayed bridges is essential to overcoming the challenges of transportation in mountainous regions, making them a preferred choice for long-span highway bridges. However, most previous research has focused on railway or rail–road applications, with limited attention paid to highway-specific designs. This paper begins with an analysis of the use and characteristics of bridges in mountainous terrains based on an investigation of 1356 bridges. A steel-box-girder cable-stayed bridge scheme is then proposed and compared to a steel-truss-girder cable-stayed bridge. The structural configurations and mechanical characteristics of the steel truss girders, towers, and cables are examined comprehensively. Innovative solutions for the critical components of steel-truss-girder cable-stayed bridges are introduced to address the unique demands posed by mountainous areas. The findings reveal that, although steel box girders offer greater stability and economic efficiency, steel truss girders provide greater structural stiffness and wind resistance, making them more suitable for large-span cable-stayed bridges in mountainous areas. The design of steel truss girders for highways features two main trusses in one of two arrangements (Pratt or Howe). The towers mainly employ H-shaped or A-shaped configurations, and stranded stay cables are predominantly used. Novel designs, including steel truss–concrete joints of hybrid girder and cable anchorage in concrete girder webs, were examined in this study via finite element analysis and model testing. The study results offer valuable insights and practical solutions for the future development of advanced steel-truss-girder cable-stayed bridges worldwide.
The construction of steel-truss-girder cable-stayed bridges is essential to overcoming the challenges of transportation in mountainous regions, making them a preferred choice for long-span highway bridges. However, most previous research has focused on railway or rail–road applications, with limited attention paid to highway-specific designs. This paper begins with an analysis of the use and characteristics of bridges in mountainous terrains based on an investigation of 1356 bridges. A steel-box-girder cable-stayed bridge scheme is then proposed and compared to a steel-truss-girder cable-stayed bridge. The structural configurations and mechanical characteristics of the steel truss girders, towers, and cables are examined comprehensively. Innovative solutions for the critical components of steel-truss-girder cable-stayed bridges are introduced to address the unique demands posed by mountainous areas. The findings reveal that, although steel box girders offer greater stability and economic efficiency, steel truss girders provide greater structural stiffness and wind resistance, making them more suitable for large-span cable-stayed bridges in mountainous areas. The design of steel truss girders for highways features two main trusses in one of two arrangements (Pratt or Howe). The towers mainly employ H-shaped or A-shaped configurations, and stranded stay cables are predominantly used. Novel designs, including steel truss–concrete joints of hybrid girder and cable anchorage in concrete girder webs, were examined in this study via finite element analysis and model testing. The study results offer valuable insights and practical solutions for the future development of advanced steel-truss-girder cable-stayed bridges worldwide.
通讯机构：
[Yao, Y ] C;Changsha Univ Sci & Technol, Sch Hydraul Engn, Changsha 410114, Peoples R China.
关键词：
Wave energy;Oscillating water column;Shore protection;Viscous energy loss
摘要：
A closely spaced U-OWC pile array with circular main tube cross-sections as both wave farm and breakwater for wave energy extraction and shore protection is investigated experimentally and numerically. The design is intended to operate in relatively deep coastal water under long-period swell conditions. In the laboratory experiments, it was found that the wave energy extraction efficiency and wave attenuation are significantly improved when U-OWC devices are integrated with pile breakwaters. The numerical model validated well with experimental data. Further applications of the numerical model have shown that compared to standalone circular U-OWC devices, the viscous loss in the U-shaped duct is less intensive when the device is placed in a pile array, and that the overall viscous loss effect in the vicinity of the U-OWC pile array is dominated by the large vortices formed by the oscillatory contraction jet flows in the narrow gaps between the piles. Compared to conventional circular OWC pile arrays, the circular U-OWC pile array demonstrated superior performance in a lower frequency range commonly found in swell conditions.
A closely spaced U-OWC pile array with circular main tube cross-sections as both wave farm and breakwater for wave energy extraction and shore protection is investigated experimentally and numerically. The design is intended to operate in relatively deep coastal water under long-period swell conditions. In the laboratory experiments, it was found that the wave energy extraction efficiency and wave attenuation are significantly improved when U-OWC devices are integrated with pile breakwaters. The numerical model validated well with experimental data. Further applications of the numerical model have shown that compared to standalone circular U-OWC devices, the viscous loss in the U-shaped duct is less intensive when the device is placed in a pile array, and that the overall viscous loss effect in the vicinity of the U-OWC pile array is dominated by the large vortices formed by the oscillatory contraction jet flows in the narrow gaps between the piles. Compared to conventional circular OWC pile arrays, the circular U-OWC pile array demonstrated superior performance in a lower frequency range commonly found in swell conditions.
作者：
Li, Huixiang;Pan, Yun;Yeh, Pat J. -F.;Zhang, Chong;Huang, Zhiyong;...
期刊：
Water Resources Research,2024年60(11):e2023WR035210- ISSN：0043-1397
通讯作者：
Pan, Y;Yeh, PJF
作者机构：
[Li, Huixiang; Pan, Yun; Gong, Huili; Zhang, Chong] Capital Normal Univ, Beijing Lab Water Resources Secur, Beijing, Peoples R China.;[Li, Huixiang; Pan, Yun; Gong, Huili; Zhang, Chong] Capital Normal Univ, MOE Key Lab Mech Prevent & Mitigat Land Subsidence, Beijing, Peoples R China.;[Li, Huixiang; Wang, Haigang; Pan, Yun; Gong, Huili; Zhang, Chong] Hebei Cangzhou Groundwater & Land Subsidence Natl, Cangzhou, Peoples R China.;[Yeh, PJF; Yeh, Pat J. -F.] Monash Univ, Dept Civil Engn, Monash, Malaysia.;[Huang, Zhiyong] Changsha Univ Sci & Technol, Sch Hydraul & Environm Engn, Changsha, Peoples R China.
通讯机构：
[Pan, Y ] C;[Yeh, PJF ] M;Capital Normal Univ, Beijing Lab Water Resources Secur, Beijing, Peoples R China.;Capital Normal Univ, MOE Key Lab Mech Prevent & Mitigat Land Subsidence, Beijing, Peoples R China.;Hebei Cangzhou Groundwater & Land Subsidence Natl, Cangzhou, Peoples R China.
关键词：
GRACE;groundwater storage change;groundwater level change;scaling factor;Scaling factor;North China plain
摘要：
To compensate for the coarse resolution of groundwater storage (GWS) estimation by the Gravity Recovery and Climate Experiment (GRACE) satellites and make better use of available observed groundwater-level (GWL) data in some aquifers, a ground-based scaling factor (SF) method is proposed here to derive high-resolution GRACE GWS estimates. Improvement is achieved by using the gridded SF derived from assimilating ground-based GWL observations. The proposed SF method is tested on the North China Plain (NCP, ∼140,000 km 2 ), where a dense network of observation wells and a consistently estimated specific yield (SY) data set are available, to demonstrate its effectiveness and practical applications. The sensitivities of SF-estimated GWS accuracy to the specification of SY and the assimilation of GWL observation data are explored through four designed numerical experiments. Results show that this novel ground-based method can reduce the impact of SY uncertainty on GWS estimates, particularly in regions with more pronounced regional GWS trends. The accuracy of SF-estimated GWS is primarily determined by whether the assimilated wells can reflect the regionally averaged GWS trend. GWS accuracy is less dependent on the number of available wells assimilated. The estimated GWS trend (2004–2015) in NCP is −32.6 ± 1.3 mm/yr (−4.6 ± 0.2 km 3 /yr), with contrasting GWS trends found in the west Piedmont Plain (∼54,000 km 2 , with a loss of −66.8 mm/yr) and the coastal Eastern Plain (∼20,000 km 2 , and a gain of +7.2 mm/yr). Despite the limitations of regional and time scale dependence inherent in SF method, this study highlights the benefits of assimilating in situ observed GWL data instead of using model simulations in estimating SF to downscale GRACE GWS to the higher-resolution that is desired by local water resources management.
A new downscaling method based on groundwater-based scaling factor correction is proposed to improve gravity recovery and climate experiment (GRACE) groundwater storage estimates
The proposed method can reduce the impact of specific yield uncertainty on groundwater storage (GWS) estimation due to the GWS information provided by the assimilated wells of groundwater level
The accuracy of GWS change based on the proposed method is primarily determined by whether the assimilated wells can reflect the regional-averaged GWS trend, less dependent on the number of available wells assimilated
期刊：
Process Safety and Environmental Protection,2024年190:1290-1300 ISSN：0957-5820
通讯作者：
Li, J
作者机构：
[Long, Yuannan; Zhang, You; Tang, Shilin; Chen, Hongwei; Li, Juan; Wen, Xiaofeng; Chen, Jianyong] Changsha Univ Sci & Technol, Sch Hydraul & Environm Engn, Changsha 410114, Peoples R China.;[Long, Yuannan; Chen, Hongwei; Wen, Xiaofeng] Key Lab Dongting Lake Aquat Ecoenvironm Control &, Changsha 410114, Peoples R China.;[Long, Yuannan; Chen, Hongwei; Wen, Xiaofeng] Key Lab Water Sediment Sci & Water Disaster Preven, Changsha 410114, Peoples R China.;[Li, Juan] Hunan Polytech Water Resources & Elect Power, Changsha 410114, Peoples R China.
通讯机构：
[Li, J ] C;Changsha Univ Sci & Technol, Sch Hydraul & Environm Engn, Changsha 410114, Peoples R China.;Hunan Polytech Water Resources & Elect Power, Changsha 410114, Peoples R China.
关键词：
Heavy metals;Surface sediment;Vertical distributions;Inner lakes;Dongting Lake area;Pollution characteristics
摘要：
The region has been increasingly experiencing environmental issues related to heavy metals (HMs) due to human activities. However, the contamination levels of HMs (Cr, Ni, Cu, Zn, As, Cd, and Pb) in various inner lakes in the Dongting Lake area remain unclear. In this study, surface sediment samples from 9 inner lakes and sediment core samples from 3 typical inner lakes were collected to evaluate the spatial distribution, contamination status, environmental and ecological risks, and possible sources of these HMs. The results showed that all HMs, except Zn, exceeded background values, with particularly high levels observed in aquaculture lakes compared to other lakes. Vertical profiles of HMs from 3 lakes show that the various types of lakes in the study area have different pollution histories. Additionally, results from Sediment quality guidelines (SQGs), Contamination factor (CF), Geo-accumulation index method (Igeo), and Hakanson potential ecological risk index (PERI) indicated that As, Cd, and Pb are the primary pollutants. The multivariate analysis concluded that Ni, Cu, Zn, As, Cd, and Pb had anthropogenic sources, primarily from agricultural, fisheries, industrial, and transportation activities, while Cr was influenced by natural factors. The results of this study enhance our understanding of sedimentary metal content in inner lakes and emphasize the importance of controlling HMs content in these lakes. This information is crucial for developing effective lake management and pollution control strategies.
The region has been increasingly experiencing environmental issues related to heavy metals (HMs) due to human activities. However, the contamination levels of HMs (Cr, Ni, Cu, Zn, As, Cd, and Pb) in various inner lakes in the Dongting Lake area remain unclear. In this study, surface sediment samples from 9 inner lakes and sediment core samples from 3 typical inner lakes were collected to evaluate the spatial distribution, contamination status, environmental and ecological risks, and possible sources of these HMs. The results showed that all HMs, except Zn, exceeded background values, with particularly high levels observed in aquaculture lakes compared to other lakes. Vertical profiles of HMs from 3 lakes show that the various types of lakes in the study area have different pollution histories. Additionally, results from Sediment quality guidelines (SQGs), Contamination factor (CF), Geo-accumulation index method (Igeo), and Hakanson potential ecological risk index (PERI) indicated that As, Cd, and Pb are the primary pollutants. The multivariate analysis concluded that Ni, Cu, Zn, As, Cd, and Pb had anthropogenic sources, primarily from agricultural, fisheries, industrial, and transportation activities, while Cr was influenced by natural factors. The results of this study enhance our understanding of sedimentary metal content in inner lakes and emphasize the importance of controlling HMs content in these lakes. This information is crucial for developing effective lake management and pollution control strategies.
摘要：
The occurrence of microplastics (MPs) and nanoplastics (NPs) in the ecosystem has received widespread attention, with research showing that their impact differs from that of conventional pollutants due to the complexity of their effect mechanisms. Constructed wetlands (CWs) as an effective wastewater treatment system using plants, substrates and biofilms can remove MPs/NPs from water bodies. MPs/NPs retained within the systems may have an impact on microorganisms, plants and other aspects of the ecological environment, thus affecting the nitrogen removal performance of CWs. Furthermore, the large specific surface area and abundant adsorption sites of MPs/NPs can result in their adsorption of coexisting environmental pollutants, heightening the potential risks posed by MPs/NPs to the ecological CWs environment. Recent studies have investigated the potential impacts of MPs/NPs on microorganisms and plants in the aquatic environments and in the soil. However, the interrelationships between MPs/NPs, microorganisms and plants in CWs and their ultimate impact on nitrogen removal are not fully understood. Therefore, it is necessary to summarize the current research progress. This review evaluates the effects of MPs/NPs and MPs/NPs carrying environmental pollutants on the nitrogen-transforming microorganisms and plant growth in CWs. The effects of changes in nitrogen-transforming microbial communities and plant growth on nitrogen removal in CWs were analyzed. This paper aims to propose practical suggestions and directions for future research on CWs and their relationship with MPs/NPs by reviewing the mechanism of influence of MPs/NPs on microbial and plant nitrogen removal in CWs.
