This study collected 616 toxicological data of 8 elements on 5 species and 3 microbial processes in 31 Chinese soils through literature collection, attempting to construct a new model for predicting the toxicity of limited elements in soil data—the Quantitative ion characteristic activity relationship (s-QICAR) model. Firstly, based on the normalization method of soil properties, the toxicity values (logEC₁₀; 1.42~3.35) of 8 elements to 5 species and 3 microbial processes were obtained under three soil scenarios of acidic, neutral, and alkaline. On this basis, the relationship between the 23 structural characteristic parameters of elements and their corresponding biological toxicity values was analyzed, and 24s-QICAR models (R²=0.70~0.98; P=0.001~0.023) were established using the covalent radius (CR) of elements. Furthermore, s-QICAR was used to predict the logEC₁₀ (1.44~3.20) of V, As, Se, and Sn for 8species. Combined with the species sensitivity distribution curve, the HC₅values of these four elements protecting 95% of organisms under three scenarios were calculated. After correction, the predicted no-effect concentrations of the four elements in acidic, neutral, and alkaline soil scenarios were V: 13, 16, 17mg/kg; As: 10, 13, 15mg/kg; Se: 4.9, 7.2, 8.4mg/kg; Sn: 42, 44, 45mg/kg, and the ecological risk threshold map for these 4elements was drawn. This study establishes a new method applicable to the ecological risk of soil elements in China, providing scientific basis for soil environmental risk assessment and management.

Sludge ceramsite and fly ash ceramsite are the two most common types of solid waste ceramsite. To compare and analyze the carbon footprint characteristics of the two types of solid waste ceramsite and quantitatively evaluate the carbon reduction benefits of the products, a carbon footprint accounting model for sludge ceramsite and fly ash ceramsite is constructed from the perspective of carbon footprint. Based on sensitivity analysis, key emission reduction factors are identified, and the carbon reduction potential of sludge ceramsite and fly ash ceramsite is predicted and evaluated through scenario analysis. Meanwhile, using error propagation equations for uncertainty analysis ensures the reliability and effectiveness of carbon footprint results. The results showed that the CO₂ emissions from the production of 1kg sludge ceramsite and 1kg fly ash ceramsite were 1.00 and 0.58 kg, respectively. The carbon footprint characteristics of sludge ceramsite and fly ash ceramsite were similar, and the ceramsite production stage was the main link in the carbon emissions of the two ceramsite particle products, accounting for 93.71% and 89.12% of their respective carbon footprints (excluding the raw material acquisition stage), respectively. The raw material structure is the most sensitive factor affecting the carbon footprint of sludge ceramsite and fly ash ceramsite, followed by the transportation structure. Compared with sludge ceramsite, the carbon footprint of fly ash ceramsite is more affected by the adjustment of raw material structure. In the scenario of collaborative optimization, the carbon emission reduction potential of simultaneously optimizing transportation and raw material structure (31%~78%) is far higher than that of simultaneously optimizing transportation and power structure (2%~5%). In addition, the emission reduction potential of the three factors acting simultaneously is the highest, reaching 33%~79%.

An inter-regional energy system optimization model, NEMO-China-MR, was constructed in this paper. Based on the economic development and energy demand differences across regions, as well as the regional resource endowments and heterogeneity in new energy development, three scenarios were designed: the reference scenario S0for steadily advancing the"carbon peaking and carbon neutrality" targets, the comprehensive scenario S1 for supply-demand coordination, and the balanced regional development scenario S2. Each scenario achieved both the "carbon peaking and carbon neutrality" targets and the transformation of energy demand while building a new power system. The scenario comparison results indicated that supply-demand coordination influenced the optimal development path of the power system. Energy storage facilities and inter-regional transmission overcame the spatial and temporal mismatches of energy resources. Scenario S1 required consideration of future grid uncertainties, while Scenario S2, which promoted healthy economic growth through balanced regional development, reduced grid transmission pressure and was identified as the most ideal development scenario for the future. Moving forward, it is essential to lead the energy system transition through high-quality economic development, construct a new power system through the coordination of electrification and low-carbon power, and build inter-regional transmission channels while promoting balanced regional development.

This research increases the accuracy of Net Primary Productivity (NPP) estimation in the CASA (Carnegie-Ames-Stanford Approach) model by refining the calculation methods for solar radiation parameters and water stress coefficients. Based on the improvement, correlation and trend analysis of NPP and meteorological variables were carried out.Following model optimization, the correlation between NPP and field observation data improved to 0.62. From 2001 to 2022, the annual average NPP in Jiangxi Province increased steadily, with the average value exceeding 1000gC/(m²⋅a). The monthly NPP values were in the following seasonal order: autumn > summer > winter > spring, with July having the highest value. The highest and lowest annual NPP values were observed in 2018 and 2010, respectively. Trend analysis and correlation facts show that, despite a decline in solar radiation from 2001 to 2022, NPP changes were not considerably impacted. A least-squares regression model revealed that NPP increased with rising temperature and decreased with decreasing sun radiation. Despite recent increases in extreme events (2019~2022), there has been no notable decrease in NPP levels.

In this study, a full-scale CANON system was constructed to treat high ammonia nitrogen iron oxide wastewater following physicochemical pretreatment. Over the course of 165days of continuous operation, the CANON system demonstrated excellent stability and shock resistance, achieving ammonia and total nitrogen removal efficiencies (TNRE) of 90% and 80%, respectively.Spearman correlation analysis and SHAP feature importance analysis were employed to elucidate the impact of water quality and environmental parameters on TNRE. Microbial community profiling unveiled substantial shifts in microbial population structures within the system, marked by the transition of the dominant anammox bacteria from Candidatus Anammoxoglobus to Candidatus Kuenenia, accounting for a relative abundance of 13.22%. Nitrosomonas was identified as the predominant ammonium-oxidizing bacteria with a relative abundance of 1.27%. Additionally, a machine learning model based on XGBoost was developed, which achieved a predictive accuracy of over 99.9% for TNRE, with a prediction precision of 98% for new data points in practical applications. This research provides valuable empirical insights into the engineering application and intelligent development of anammox processes.

An innovative technique for extracting phosphorus and synthesizing high-purity vivianite from incinerated sewage sludge ash was explored in this investigation, which experienced three principal stages, including leaching with sulfuric acid, purification via resin adsorption, and crystallization through iron electrocoagulation. The optimal conditions for acid leaching of phosphate (PO₄^3-)from incinerated sewage sludge ash were examined by the response surface methodology, and the optimal operational parameters for the iron electrocoagulation process were determined by the Box-Behnken Design. The results indicate that phosphorus extraction efficiency of 92.80% was achieved at a liquid-to-solid ratio of 37.60mL/g, a sulfuric acid concentration of 0.125mol/L, and an acid leaching duration of 90.0min, the metal cations interfering with phosphate precipitation, such as Ca²⁺, Mg²⁺, Al³⁺, and Fe^2+/3+ were efficiently removed by 732cation exchange resin, all phosphorus was removed from the solution successfully during the iron electrocoagulation process at an initial solution pH value of 2.00, a current of 2.00A, and a reaction time of 30.0min, meanwhile, vivianite with a purity of 97.37% were synthesized. The outcomes show that the three-step method facilitates phosphorus recovery from incinerated sewage sludge ash. 61.44% of the phosphorus was retrieved as high-purity vivianite through the three steps; the recovery process costs 14.66yuan per kilogram product of vivianite and yields a profit of 30.68yuan.

The degradation efficiency of various emerging pollutants by potassium ferrate (Fe(VI)) catalysed through magnetic biochar (MC) prepared using hydrothermal-calcination method was investigated. The reactive species in M-BC/Fe(VI) system and the effects of the dosage of M-BC, Fe(VI), pH value and natural organic matters on the degradation efficiency of sulfamethoxazole(SMX) were studied. The results indicated that the removal of SMX by alone M-BC (50mg/L) and Fe(VI) (50µmol/L) were 3.5% and 54.1% during 20min, respectively, while the M-BC/Fe(VI) system achieved an SMX degradation rate of 89.6%. Experiments with probe compounds and inhibitors confirmed that the primary reactive species in the system were intermediate valence iron(Fe(V)/Fe(IV)). Fourier-transform infrared spectroscopy analysis revealed that the main active sites on M-BC were surface phenolic hydroxyl groups. Under pH conditions of 8, increasing the dosages of Fe(VI) and M-BC enhanced the removal of SMX by the M-BC/Fe(VI) system. Compared to the alone Fe(VI) system, the degradation of SMX in the M-BC/Fe(VI) system was increased by 114%, 63.6%, 300%, and 350% at pH 7, 8, 9, and 10, respectively. Low concentrations of natural organic matter (1mg/L) promoted the degradation of SMX by the M-BC/Fe(VI) system, but high concentrations of natural organic matter (5~10mg/L) competed with SMX for Fe(VI) and Fe(V)/Fe(IV) , leading to a decrease in the degradation efficiency of SMX. Additionally, the M-BC/Fe(VI) system achieved SMX degradation of 100% and 83.7% in spring and Yellow River water, highlighting its potential for practical application in water treatment process.

This study aims to investigate the VOCs pollution characteristics in the high-tech industrial zone of Tongchuan City, a medium-sized city in the Fenwei Plain, by using online monitoring methods to measure the concentration of environmental VOCs components (a total of 115species) in the atmosphere of the Tongchuan High-tech Industrial Development Zone, thereby obtaining a high-resolution time series and seasonal variation patterns of atmospheric VOCs. The Positive Matrix Factorization(PMF) model was utilized to identify the primary sources of VOCs, and the Maximum Incremental Reactivity (MIR) method was applied to quantify the Ozone Formation Potential (OFP) of VOCs. Furthermore, the Hazard Index (HI) and Lifetime Cancer Risk (LCR) of toxic VOCs were calculated. The findings revealed that during the monitoring period, the average values of φ (TVOCs) in spring, summer, and winter were respectively (69.03 ± 47.48)×10^-9, (92.66 ± 37.54)×10^-9, and (134.90± 74.58)×10^-9, with the top three components in each season being consistent (alkanes > alkenes > aromatics). PMF source apportionment results indicated that the sources of atmospheric VOCs in the development zone were primarily from chemical companies, motor vehicles, and combustion emissions (each contributing over 20%). OFP assessment outcomes revealed that OVOCs were the major contributing components in all seasons, with ethanol, acetaldehyde, and ethylene being the primary species. Health risk assessments indicated that the HI in spring, summer, and winter all exceeded acceptable levels (HI > 1), suggesting non-carcinogenic health risks to the exposed population. Acrolein, in particular, had a notably high hazard index, exceeding 1in all seasons. The lifetime cancer risks in spring, summer, and winter were 1.68×10^-5, 1.57×10^-5, and 8.42×10^-5, respectively, indicating a slight carcinogenic risk in all seasons.

This paper combined multi-source data to develop the identification approach of VOCs high-emission areas during ozone pollution season (from May to September). At the same time, the spatial distribution pattern and long-term change trend of VOCs during the ozone pollution season in Beijing from 2005 to 2023 was examined and discussed based on satellite-derived HCHO column concentration. The results showed that the concentration of VOCs in Beijing is at a high level within the Beijing-Tianjin-Hebei region, and its distribution was significantly affected by human activities. The total amount of HCHO in the areas of anthropogenic sources dominated was 3.4times of that of natural sources dominated. The high emission areas of anthropogenic sources mostly appeared in the northern, central eastern, and southwestern parts of the urban area of Beijing City.Approximately 61% of the areas were sources of industrial production process and solvent usage, and mainly distributed outside the Fifth Ring Road. Approximately 39% of them were sources of automobile maintenance, logistics warehousing etc., and mainly distributed along highways. This identification method has improved the effectiveness of ozone pollution prevention and control work in the summer of 2023, offering technical support for locating key regulatory objects and areas. From the perspective of interannual variations, the column concentration of VOCs in Beijing showed an increasing trend from 2005 to 2018, with an increase of about 26% (after correction of temperature), while it showed a downward trend from 2018 to 2023, with a decrease of about 11%, reflecting the effectiveness of VOCs emission control in recent years.

Based on the unique hydrodynamic and environmental conditions of stormwater artificial recharge, a series of one-dimensional seepage simulation experiments were conducted. The migration and deposition characteristics of clogging microorganisms within porous media under varying seepage conditions, such as different saturation levels, pH environments, ionic strengths, and recharge rates were systematically analyzed and the development of bioclogging within porous media under different seepage conditions was clarified. DLVO theory was used to reveal the dominant forces during microbial migration under different pH environments and ionic strengths. The results showed that the migration of microorganisms slowed down as saturation decreased, pH lowered, ionic strength of the recharge water increased, or recharge flow rate decreased. Consequently, deposition on the medium increased, while interlayer deposition became more uniform, promoting the formation of bioclogging within the medium. Changes in saturation, pH, or ionic strength had minimal effect on microbial migration when saturation was between 60% and 80%, pH was between 7.5 and 8.5, or ionic strength was between 1and 5mmol/L. Under unsaturated conditions, the impact of recharge rate variations on microbial migration and deposition was weakened when the recharge rate was within the range of 0.5to 1mL/min. Under different pH environments and ionic strengths, the dominant forces during microbial migration in saturated and unsaturated media were electrostatic forces and capillary forces, respectively.