## 4 Conclusions
Financial or technical constraints hindering small-scale STPs should be addressed through flexible incentives, such as subsidized technology upgrades or preferential tax exemptions. 3. Integration into Existing Management Systems:  
Incorporate carbon emission metrics (absolute emissions and emission intensity) into the current wastewater sector governance framework. This integration would enable performance benchmarking and facilitate targeted mitigation strategies. 4. Carbon Mitigation Incentives:  
Develop government-led incentive programs, including emission reduction subsidies and tax relief, to encourage synergistic pollution control and carbon reduction. Small-scale STPs facing financial or technical limitations should receive prioritized support through relaxed eligibility criteria or enhanced grant allocations. Technological and Methodological Advancements:  
1. Dynamic Emission Modeling: Conduct pilot studies on dynamic emission modeling and low-carbon technology applications for high-emission STPs to guide operational transformation toward carbon neutrality. 2. Real-Time Monitoring Systems: Deploy online greenhouse gas monitoring systems (e.g., for CO\({}_{2}\), CH\({}_{4}\), N\({}_{2}\)O) in underground STPs or facilities with odor control installations. Such systems would enable precise quantification of real-time emission profiles, offering superior accuracy compared to conventional calculation frameworks. Study Limitations and Future Directions:  
This research has several limitations. First, indirect emissions from sludge treatment processes were excluded from the analysis. Second, the study assumed constant emission factors throughout the treatment lifecycle, neglecting potential spatiotemporal variability. Future investigations should incorporate life cycle assessment (LCA) methodologies to account for upstream/downstream emissions and validate emission factors under diverse operational conditions. **Author Contributions:** Conceptualization, H.W. ; Methodology, H.W. and L.L. ; Validation, X.Z. ; Formal analysis, Z.L. ; Investigation, H.W. and Z.L. ; Resources, H.W. and Z.L. ; Data curation, X.Z. and Z.L. ; Writing--original draft preparation, Z.L. ; Writing--review and editing, Y.T. ; Visualization, Z.L. ; Supervision, L.L. ; Project administration, L.L. ; Funding acquisition, L.L. All authors have read and agreed to the published version of the manuscript. **Funding:** Supported by the State Key Laboratory of Urban Water Resource and Environment (Harbin Institute of Technology) (No. 2024 TS14), the Innovative Research Group of the National Natural Science Foundation of China (No. 52321005), and the National Key R&D Program of China (2022 YFC3801101). **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable. **Data Availability Statement:** The data used in this article are not made public. If you need to use them, please contact the corresponding author. **Conflicts of Interest:** Author [PERSON] was employed by the company Beijing Enterprises Water Group Limited (BEWG). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.