昌平区"23·7"洪水小流域水土保持调查及启示OA

From July 29 to August 2,2023,under the combined influence of the weakened low-pressure circulation of Typhoon Doksuri and a cold air mass,Changping District in Beijing experienced persistent intense storm,leading to severe soil erosion disasters.After the flood,a comprehensive soil and water conservation investigation was conducted in four small mountainous watersheds—Langeryu,Wangjiayuan,Xiangtan,and Yangtaizi—utilizing modern techniques such as GIS and drone aerial photography,combined with field sampling surveys.The results indicate:① The rainfall in the four small watersheds ranged from 351.5 mm to 479.5 mm,with total flood volumes between 4.525 4 million m3 and 20.805 7 million m3.② The flood caused severe soil erosion,with water erosion modulus in the four watersheds increasing to 50-161 times that before the storm,and the average damage rate of terraced fields reaching 5.97%.③Watersheds with higher levels of management and more comprehensive soil and water conservation measures exhibited less soil loss and lower damage rates.Based on the findings,the following recommendations are proposed:① Enhance soil erosion prevention standards to improve resilience against natural disasters.② Strengthen operational management and maintenance to minimize soil erosion.③ Reinforce soil and water conservation plans for production and construction projects in mountainous areas to control erosion at the source.