Anammox is a promising approach for biological nitrogen removal, but the differences in microbial community structure across different systems and their response mechanisms to environmental factors remain unclear. In this study, 206 microbial samples and 2126 environmental factor data points from three different anammox systems, including the upflow anaerobic sludge blanket (UASB), integrated fixed-film activated sludge-partial nitritation/anammox (IFAS-PN/A), and integrated fixed-film activated sludge-simultaneous nitrification, anammox and denitrification (IFAS-SNAD), were analyzed using 16S rRNA sequencing analysis, bioinformatics, and machine learning (ML) techniques. The results revealed significant differences in microbial composition among three systems, evidenced by the enrichment of Candidatus_Brocadia in IFAS-PN/A, the high-diversity community in IFAS-SNAD, and the low-diversity communities dominated by Candidatus_Kuenenia in the UASB. Co-occurrence network analysis demonstrated more tightly connected and complex interactions in IFAS-SNAD networks. Machine learning predictions further showed that the stacked model (ST-RF) achieved the highest accuracy in predicting the nitrogen removal rate (NRR), with determination coefficients (R²) exceeding 0.987 across all testing datasets. Moreover, SHapley Additive exPlanations (SHAP) analysis based on the stacked model revealed that the influence of key environmental factors on NRR varied by system type. These results suggested that NRR of different systems depended on the control of key environmental factors, while the significance of these environmental factors was determined by the type of system. Overall, this study enhanced the ecological and functional understanding of anammox-based processes and provided a data-driven framework for optimizing mainstream nitrogen removal.

The Western Route of the South-to-North Water Diversion Project is a significant water conservancy project that has undergone years of discussion. This study employed the emergy method to evaluate the ecosystem service value (ESV) of its water source areas from 2002 to 2022, analyzing spatial heterogeneity, and evaluating trade-offs and synergies among ecosystem services. The high-emergy areas for water supply are concentrated in the lower reaches of the basin, Liangshan Prefecture had the highest emergy, increasing from 1.14 × 10²¹ sej to 1.65 × 10²¹ sej over the 20 years. The climate regulation emergy values of Ganzi Prefecture, Aba Prefecture, and Liangshan Prefecture were relatively stable. The biodiversity remained relatively stable with small fluctuations, but exhibited significant spatial heterogeneity. Liangshan Prefecture and Lijiang City had the highest biodiversity emergy values, at 1.21 × 10²¹ sej and 2.05 × 10²¹ sej respectively, corresponding to as many as 7661 and 13,000 species, respectively. Among the service types, provisioning services and supporting services account for a relatively high proportion. The water supply increased by 6.13%, while the biodiversity decreased by 5.42%. The relationship showed particularly intense conflict of −0.965. Analyzing the spatiotemporal evolution of ESV in water source areas is of great significance for rationally guiding the phased and seasonal allocation of water transfer volumes, implementing ecological compensation, and assessing the impacts of water conservancy projects on the ecological environment.

Most of the pipelines of oil and gas pipelines in our country have been for more than 25 years. These pipes are buried underground and was difficult to daily test. In addition, it was vulnerable to environmental, corrosion and natural disasters, So there is a hidden nature of accidents. The rapid development of urbanization, population accumulation, dense building and insufficient safety range are all the reasons for the frequent accidents of oil and gas pipelines. Therefore, to appraise and know the safe condition of the city various regions oil and gas pipelines is vital significant. In order to ensure the safety of oil and gas pipeline city, this paper defines the connotation of oil and gas pipeline city vulnerability according to the previous research on vulnerability. Then from three perspectives of environment, structure and behavior, based on the analytical paradigm of “structure—vulnerability conduct—performance” about oil and gas, the influential indicators of vulnerable oil and gas pipelines were analysed, the vulnerability mechanism framework of Oil and gas pipeline city was also constructed. Finally, the paper proposed the regulating strategy of the vulnerability of the oil and gas pipeline city to decrease its vulnerability index, which can be realize the city’s vulnerability evaluation and provides new ideas for the sustainable development of the city.

We have demonstrated a facile and economical method for the synthesis of the sewage sludge-derived carbon. This product was prepared by using poly-aluminium chloride (PAC) as pore-forming agent through high-temperature pyrolysis at 900℃, and employed for the removal of phenol from water. Thermodynamic properties, textural evolution, morphological structure, and surface functional groups of product are characterized. Moreover, the total pore volumes and SSA of the residual carbon increased to 0.1727 cm 3 /g and 141.2 m 2 /g, that expanded to 2.3 times and 2.5 times compared with direct carbonized sample (0.075 cm 3 /g and 55.45 m 2 /g), respectively. The results indicated that the addition of PAC had important effect on the texture, surface properties and adsorption performance. The adsorption kinetics and isotherms studies were investigated in details to reveal that the kinetics and equilibrium adsorptions are well-described by pseudo-second-order kinetics and Langmuir isotherm model, respectively. Remarkably, the resulting adsorbent showed comparably adsorption capacity with the commercial activated carbons. Meanwhile, our method is more economical than other chemical activation methods.