北京市河流水生态健康时空异质性及改善路径研究

Study on Temporal and Spatial Heterogeneity of Aquatic Health and Improvement Paths of Rivers in Beijing

河流生态系统是人类社会得以生存与发展的基本条件,河流水生态健康对保障区域水安全,避免水灾害具有重要意义。随着城市化的不断推进,河流生态系统面临着巨大挑战,水生态风险及灾害呈现广发、频发和深发态势。通过汇总北京市五大流域河流水生态健康状况评估相关研究,识别区域水生态系统主要问题,诊断水生态健康问题产生的原因。结果表明,北京市河流水生态系统健康状况具有较强的时空异质性。空间上,各流域河流水生态健康状况为潮白河>永定河>蓟运河>清水河>北运河。上游河段水生态健康状况好于中下游,山区段河流好于平原段。水资源短缺引起的河流生态基流不足、水污染物超量排放造成的水质不达标、粗放式河流水利工程建设、河流水土资源的不合理开发以及河流植被缓冲带的不足等是造成河流水生态健康问题主要原因。并针对病因提出河流水生态健康目标导向的改善路径,以期为北京市及其他北方缺水性城市河流水生态健康改善及水安全保障提供参考。

River ecosystem is the basic condition for the survival and development of human society.The river aquatic health is of great significance for ensuring regional water safety and avoiding water disasters.With the continuous advancement of urbanization,river ecosystems are facing huge challenges,and aquatic ecological risks and disasters are showing a trend of widespread,frequent and deep-occurring.Based on a review of the research on the assessment of the ecological health of the five major water systems in Beijing,the major problems of regional aquatic ecosystems are identified,and the causes of aquatic health problems are further diagnosed.The results show that the health status of river ecosystems has strong spatial heterogeneity in Beijing.In general,comparison of aquatic ecological health status of rivers in different river basins is Chaobai River>Yongding River Basin>Ji Canal Basin>Qingshui River Basin>Bei Canal Basin.The health status of water ecology in the upper reaches is better than that in the middle and lower reaches,and the rivers in the mountain sections are better than the plain sections.Insufficient river ecological basic flow caused by water shortage,water quality failure caused by excessive discharge of water pollutants,extensive river water conservancy project construction,unreasonable development of river water and soil resources,and insufficient river vegetation buffer zone are the main causes of health problems.To the problem,a health improvement path led by river water ecological health is proposed.With a view to transforming the management of Beijing’s aquatic environment from water pollution prevention to aquatic protection,it will provide a reference for improving the aquatic ecological health of rivers in Beijing and other cities.