Study Of The Relationship Between Topography Multi-fractal Characteristics And Spatial Distribution Of Geological Disaster In Wenzhou City Based On GIS

Geomorphology is one of the necessary factors that affect the occurrence and distribution of geological disasters, the distribution of one of the factors necessary, the quantitive research of geomorphology character and spatial distribution character of geological disasters is significant to prevent geological disasters, and it can have base for developing disaster evaluation and forecast. In recent years, fractal theory has been developed in geological and seismal field, but is presently still in its beginning in geological disaster field. Therefore it is practically significant to incorporate these modern GIS techniques with fractal theory to develop a new way to study the spatial distribution character of geological disasters.This article firstly introduces the quantitative model of topography multi-fractal characteristics and the implement process on GIS. Secondly, statistically analyses the main types of Wenzhou geological disasters characteristics in space-time, summarizes the spatial distribution characteristics of main types of geological disasters. Then, based on multi-fractal theory, combined with GIS technology, this article calculates the topography multi-fractal data of various districts and counties and the typical township of Wenzhou, analyses the topography multi-fractal characteristics of various districts and counties. Finally, has founded the coupled model on the relationship between the topography multi-fractal characteristics and the number of geological disasters, revealed the quantitative coupling relationship between the geological multi-fractal characteristics and spatial distribution of disasters in Wenzhou city.In this paper, the results show that the topography of Wenzhou is remarkable form of multi-fractal characteristics. There is a positive correlation between the scope of topography change singular index(Δa)and multi-fractal spectrum absolute value of elevation( |Δf | )and topographic complexity, that is, with the greaterΔa and |Δf | are, the more topographic complexity will be. Moreover, there is a positive correlation between topography multi-fractal characteristics and the geological disasters, its change can be broadly divided into three levels: WhenΔa <0.100, there is a positive correlation betweenΔa and the number of disasters, but the number of disasters occurred is small in this section; when 0.100 <Δa <0.134, the number of disasters are relatively fluctuatal, indicating that whenΔa is in this region, there is the instability phenomenon of landslide disasters, showing a certain degree of volatility; when 0.134 <Δa <0.157, geological disasters is more prone to occur in this region.Therefore, this paper researches the quantitative coupling relationship between the geological multi-fractal characteristics and spatial distribution of disasters in Wenzhou City. clarifies the rationality that it takes characteristics of topography multi-fractal as a comprehensive quantitative index, and provides a quantitative scientific data for the study of spatial distribution of disasters in Wenzhou City. and provides important scientific basis for the evaluation, prevention and treatment of geological disasters in the region.