Analysis of scientific collaboration and hotspots in fish passage facilities at home and abroad

Fish crossing facilities are essential for maintaining the ecological balance of aquatic systems and safeguarding fish populations. This study utilizes CNKI and Web of Science as data sources, employing bibliometric analysis to construct knowledge maps. The objective is to systematically review and synthesize the current research status and emerging trends in this field. The key findings are as follows: (1) Research efforts in fish passage infrastructure are predominantly concentrated in North America, Europe, and East Asia, with leading institutions being primarily scientific research institutes and universities. Author collaboration networks exhibit a pronounced "institutional network" characteristic; (2) International research tends to emphasize ecological integrity assessments and multi-species compatibility in fish passage design, whereas domestic research focuses on protecting endemic migratory fish species and assessing the adaptability of fish passages in specific regions such as the southwest basin, middle and lower reaches of the Yangtze River, Yellow River, and Pearl River basins; (3) A substantial body of practical explorations has been conducted both domestically and internationally in areas such as structural design, hydraulic characteristics, and fish behavior. Indoor hydraulics and fish behavior tests are widely utilized as foundational support technologies. International research increasingly integrates long-term ecological field monitoring data with the mechanisms of fish behavior, while domestic research focuses more on the innovative application of numerical simulation technologies; (4) Current research primarily explores hydraulic characteristics through model testing and numerical simulations, with emerging frontiers extending to deep learning-assisted assessment and monitoring, as well as fish response mechanisms under global climate change. Domestic research is expanding from structural optimization to ecological impact assessment and watershed system governance.