基于GIS空间分析的森林防火蓄水池选址

On the locality selection of the forest fire prevention reservoirs based on the spatial analysis of GIS

针对消防蓄水池这一山区储水设施的选址问题,基于地面25m×25 m单元的空间分析方法(如水文分析、重分类、距离制图等),以安宁市为试验区,获取其累积汇水量,并结合该地森林火险等级和道路网络空间分布,采用综合打分方法得出森林防火蓄水池选址适宜度,最终通过人机交互判别选取了汇水量高、所辐射的森林面积均匀合理、用水方便的区域作为蓄水池地址。研究表明,该技术方法具有一定普适性,对山地森林消防蓄水池建设有参考作用。

The paper cherishes its research goal on how to properly choose the location for forest fire prevention and extinguishing reser- voirs based on the spatial analysis of G1S technology. It is emergent to study how to build up such reservoirs more efficiently. However, to resolve the above problems, a key technical problem is to choose a proper location in the complicated mountainous areas in traditional methods. In proceedi1~g with our research, this paper has chosen An- ning City, Yunnan, as a case study sample to show how to choose such localities for such firefighting reservoirs via GIS method. First of all, in accordance with the original GIS data, we have managed to use the digital elevation model（DEM） by digitalizing the topographic maps in a scale of 1：50 000. Secondly, we have done a very detailed hydrologic analysis to establish a motion model of the surface water runoff registration based on DEM at a resolution of 25 m, in which we have calculated the actual water accumulation situation in any unit of 25 m x 25 m while taking into account the rain-water flowing direction and the flowing：water accumulation tools by using a software named ArcGIS. In addition, we have made a detailed map of catchment area by the water accumulation. Thirdly, we have worked out a map to show the convenient routes to reach the said mountainous areas and their respective distances from each other to represent the convenient grades for getting water. And, fourthly, we have made the fire dan- ger rating map vectored firstly and then rasterized by the existing fire danger rating map. And, fifthly, when reclassifying the catchment area, the distance of the roads and the fire danger rating map, we have worked out the suitability of the sites for reservoirs for for^t fire prevention in a comprehensive scoring manner by weighing the above said influential factors in a percentage term, such as 50%, 30%, 20 %, respectively, in accordance with the point of view and experi- ence of the experts concerned. The results of our investigation and design have shown that Qinglong and Wenquan towns in Arming City are suitable for building such reservoirs for firefighting risks. And, fi- nally, we have chosen the optimal sites of reservoirs via human-com- puter interaction calculation, which are separately located in the areas of Qinglong, Wenquan, Caopu, Xianjie since all the Said sites in town Bajie are all not far away from the river of Chemu. What is more, the results of our choice are all believed to meet the needs of high water accumulation, the rational radiation for forest areas and convenient enough for water fetching. Thus, the technique based on the spatial analysis of GIS （：an be taken as a generally popularized reference to the choice of forest fire prevention reservoirs in the mountainous areas.