摘要
合理的雨量阈值指标是区域暴雨泥石流防灾减灾的关键所在。以甘肃舟曲三眼峪为研究对象,采用水文学分析方法,计算了不同降雨频率下洪水特征值以及不同规模的泥石流启动降雨量阈值,并将诱发泥石流的降雨预警级别划分为红、橙、黄、蓝四个预警级别和两个预备预警级别。结果表明:三眼峪小流域在前期干旱和一般条件下泥石流红色Ⅰ级降雨预警值分别为56.10 mm/h和50.86 mm/h,橙色Ⅱ级预警值分别为40.70 mm/h和37.87 mm/h,黄色Ⅲ级预警值分别为31.74 mm/h和29.88 mm/h,蓝色Ⅳ级预警值分别为23.83 mm/h和21.69 mm/h,预备Ⅴ级预警值分别为17.31 mm/h和15.69 mm/h,预备Ⅵ级预警值分别为10.16 mm/h和9.48mm/h。同时建立了在前期一般和干旱两种条件下,不同预警级别的泥石流降雨雨强与历时阈值关系,研究成果可为区域减灾防灾和科学研究提供依据。
Reasonable rainfall thresholds for the initiation of landslides may play a role in helping mitigating landslide risk. In this study,with Sanyanyu Valley,Zhouqu,as the research object,we calculate the flood characteristic values at different frequencies and their corresponding rainfall thresholds for initiating debris flows of different scales by using the hydrological method. We also divide the early warnings for rainfalls that might induce debris flow into four levels,i. e.,red,orange,yellow and blue,and two preparation and early warning levels. The results show that,for the two early soil states in Sanyanyu Valley,the Level I red early warning values for rainfall inducing debris flow are 56. 10 mm / h and 50. 86 mm / h respectively,the Level II orange early warning values are40. 70 mm / h and 37. 87 mm / h respectively,the Level III yellow early warning values are 31. 74 mm / h and 29. 88 mm / h respectively,the Level IV blue early warning values are 23. 83 mm / h and 21. 69 mm / h respectively,the Level V preliminary early warning values are 7. 31 mm / h and 15. 69 mm / h respectively,and the Level VI preliminary early warning values are 10. 16 mm / h and 9. 48 mm / h respectively. It established the function relationship between the intensity and duration of the rainfalls triggering debris flows of different early warning levels under two early soil states,i. e.,moist and arid in Sanyanyu Valley. The research results can provide scientific bases for regional disaster prevention and reduction and scientific research for Zhouqu.
出处
《灾害学》
CSCD
2016年第1期25-28,共4页
Journal of Catastrophology
基金
国家自然科学基金项目(41302224)
陕西省科学技术研究发展计划项目(2014KJXX-20)
国家地质找矿专项(12120114025901)
关键词
舟曲
三眼峪
泥石流
降雨
临界阈值
Zhouqu
Sanyanyu Valley
debris flow
rainfall
threshold
