陇东黄土区地质灾害气象预警方法与应用——以泾川县为例

Study on and Application of Geological Hazards Meteorological Early-warning in the Loess Area: A Study in Jingchuan County in Eastern Gansu Province of China

在地质灾害详细调查的基础上,基于GIS平台以地质灾害点密度为依据生成初步地质灾害易发性区划图。从诱发地质灾害的内部因素出发将地层岩性、地形坡度、地貌类型、植被覆盖率、多年降雨量分级后,叠加到初步易发性区划图中,生成了地质灾害气象预警区划基图。以降雨作为诱发地质灾害的主导外在因素,重新对泾川县进行了地质灾害气象预警区划,在重点预警区及次重点预警区采用临界日综合有效过程降雨量模型判据法,开展地质灾害气象预警预报研究。通过实际发布预警信息的检验结果来看,从总体上取得了较好的预报效果,该方法符合该区的实际情况,简捷、实用、有效,为进一步研究陇东黄土区地质灾害气象预警提供科学依据。

In this paper,according to detailed investigation of geological disasters,we firstly generated preliminary geological hazard susceptibility zoning based on geological disasters points＇ density on the GIS platform.Secondly,we classified the internal factors of geological hazards such as lithology,terrain slope,landform types,vegetation coverage rates,and multi-annual rainfall and so on.Then we covered the classification of internal factors to the preliminary geological hazard susceptibility zoning and generated the geological hazards meteorological early-warning based map.And,respect rainfall as the dominant external factors of geological hazards,we rezoned the geological hazards meteorological early-warning map in Jingchuan County.Finally,we employed the critical-day synthesized criterion of precipitation method in the key and secondary warning zones of Jingchuan County.Good prediction results were obtained through the actual test,which indicate that,being simple,practical and effective in the actual situation of the area,it can provide a scientific basis for the further study of geological hazards meteorological early-warning in the Loess Region of eastern Gansu Province.