分形理论在达州市达川区滑坡灾害研究中的应用

分析诱发滑坡灾害的原因是一项较为复杂的过程。针对四川省达州市达川区各种自然因素开展研究,通过GIS软件的分析功能,得到研究区395个滑坡灾害点与各个影响因素的叠加图。利用分形分维理论中的盒维数法研究达川区滑坡灾害点空间分布的分形特征,并对统计结果进行分析。研究成果显示:达川区滑坡灾害点空间分布分维值为1. 011 9,相关系数为0. 956 4,具有较高的自相关性;按各自然因素分区统计,滑坡灾害点与深丘、低山地区,年均降水量介于1 050～1 250 mm以及植被覆盖度介于30%～60%之间的区域分形相关性都较强。因此,采用分维值划分滑坡灾害易发程度,可以更直观地描述各影响因子对滑坡灾害点影响程度并得到潜在灾害危险性分区示意图,可以为滑坡灾害的有效治理提供可视化数据支撑。

Application of fractal theory to landslide disaster research in Dachuan District,Dazhou City

Analyzing the cause of landslide hazard is a complicated process. This paper obtained the overlay of 395 landslide hazards and various influencing factors in Dachuan District of Dazhou City, Sichuan Province by using analysis function of GIS software. Then, we studied the fractal characteristics of spatial distribution of landslide disasters in Dachuan District by box dimension method of fractal dimension theory and analyzed the statistical results. Research results showed that the fractal dimension of spatial distribution of the landslides in Dachuan district was 1.011 9, and the correlation coefficient was 0.956 4, showing high auto-correlation. Zoning statistics according to various natural factors showed that the fractal correlations were high in deep hilly and low mountain area as well as the area where the average annual rainfall was 1 050~1 250 mm or the vegetation coverage was 30%~60%. Therefore, using fractal dimension to divide the vulnerability of landslide disaster can describe the influencing degree of each influencing factor on landslide disaster point more intuitively and obtain the map of potential disaster risk zoning. It can provide visual data support for the effective management of landslide disasters.