Safety and ecological health are restricted by the high amount of suspended sediment in the Yellow River. To solve the problems of the high sediment content and siltation in the Yellow River, the Xiaolangdi Reservoir (XLDR) has been carrying out water–sediment regulation (WSR) since 2002. To clarify the effects of the water and sediment changes caused by WSR on microbial communities, we analysed the composition of the microbial communities and functional groups in surface water and sediments before and after WSR using high-throughput sequencing and microbial functional annotation. Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes were detected as the main microbial communities in the Yellow River’s middle and lower reaches. The water temperature (WT), dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP), and evolution of the microbial communities were all correlated (p < 0.05). The biodiversity indices of the surface water and sediment microbes, respectively, greatly declined. The WSR programme broke down nutrients that had been adsorbed on the sediments, which diminished microbial metabolic activity and impaired the water bodies’ capacity to purify themselves. In summary, this study provides the biological information needed for the ecological conservation of the Yellow River basin, as well as insights into the changes in and response characteristics of microorganisms following severe disturbances in rivers with high sediment concentrations.

The emergence of smart campuses marks a pivotal advancement in educational pedagogy, environmental quality, resource allocation, and administrative services. This study presents the conceptualization and implementation of the Nanxun Campus of Zhejiang University of Water Resources and Electric Power (ZJWEU), which serves as an exemplary smart water initiative. Adhering to the philosophy of integrating educational facilities within the campus infrastructure, the campus incorporates several specialized zones: a key protection area, the water conservation area, the ecological stability area, the living water spirit area, and the teaching and practice area. This study clarifies the unique attributes, design philosophies, and operational mechanisms of these distinct zones. Central to the campus’s identity is a water culture-centric strategy, with each building reflecting water-themed concepts and providing extensive real-world engineering teaching and practice environments. Since its opening in 2022, the campus has been admitting approximately 5000 students annually and has been a model of water culture campuses that integrate ecology, intelligence, humanism, and synergy. The insights and infrastructure provide a valuable reference and foundational support for the evolution of smart campuses, underscoring the potential to merge water culture with avant-garde educational practices.

Multi-scenario flood simulation supports urban flood-risk assessment, but scenario-specific outputs are difficult to use to identify facility-level risk evolution and critical risk conditions. This study proposes a multi-scenario flood risk reasoning method for critical urban facilities based on facility–scenario risk chains (FSRCs). The method constructs internally comparable rainfall–inundation scenario subsets, anchors each facility to a fixed triangular mesh cell, and organizes inundation depths and depth-based risk states into ordered chains. Boundary-crossing reasoning is then used to derive scenario-context-dependent critical rainfall threshold (CRT) estimates and ordered risk-state transition sequences. The method was evaluated in the Hexi drainage area of Nanjing, China, using 184 rainfall–inundation scenarios and 241 critical facilities. The results show that accumulated rainfall alone is insufficient for consistent risk ordering across different rainfall durations, while facility risk states vary across comparable rainfall-ordered scenario sequences. Representative facilities exhibited distinct CRT positions and transition intervals. Sensitivity analysis showed that CRT estimates varied with scenario spacing, while a computational consistency assessment confirmed the reproducibility of boundary-crossing results. The proposed method transforms discrete flood simulation outputs into structured object-level risk knowledge, supporting facility-level risk screening, risk-state comparison, and subsequent knowledge-driven applications.

As a representative large shallow freshwater lake in China, Lake Taihu has suffered from persistent cyanobacterial blooms for a long time. Although intensive restoration actions have been carried out and caused visible improvements, the long-term evolution path and inner driving mechanisms of its ecosystem are still not fully made clear. Based on long-term monitoring data during 2011 to 2024, this study aims to characterize temporal dynamics of the aquatic environment, find out key drivers that shape community succession, and offer a scientific foundation for effective lake management. A series of data about hydrometeorological factors, physicochemical water quality indexes, and biological community data was analyzed by using the Mann–Kendall trend test, Pettitt change-point test, Redundancy Analysis, and correlation heatmaps. The results show that the Taihu ecosystem has experienced a notable regime shift in the past 14 years. First, nitrogenous nutrients reacted quickly to external emission reductions, showing a notable monotonic decline; in comparison, Total Phosphorus and Cyanobacterial Density followed a non-linear “U-shaped” path, with a notable shift happening in 2020, which marks the change from a “deterioration phase” to a “recovery phase.” Second, correlation analysis has confirmed that the lake is mainly phosphorus-limited, and a clear “decoupling” between nitrogen levels and algal outbreaks has taken place. Third, the “10-year Fishing Ban” (initiated in 2020), together with sustained phosphorus control, reduced the competitive exclusion of phytoplankton by cyanobacteria, promoting the recent rebound in biodiversity. This study points out that Lake Taihu has passed a tipping point of ecological restoration, shifting from a turbid “algae-dominated state” to a stable state with higher biodiversity. Future management strategies should put first the mitigation of internal phosphorus loading and adaptive management against extreme climatic events.