Construction And Application Of Terrain Complexity Model Based On Improved Fractal Algorithm

Terrain complexity,as an important parameter in the field of geoscience research,carries many important information such as the height of the terrain,the degree of surface roughness,and the direction of the terrain.Terrain complexity is widely used in many fields such as surveying and mapping,geology,remote sensing,agriculture and forestry production,urban construction,and geological disaster analysis.Therefore,it is of practical significance to accurately and effectively quantify terrain complexity.At present,there are many methods for quantifying terrain complexity.Based on the fractal theory,this paper builds on the previous research and builds a complex terrain quantification model based on an improved fractal algorithm,and applies the model to spatial sensitivity analysis of landslide geohazards.To do this,I did the following:First,the scientific meaning of terrain complexity and its research status at home and abroad are summarized.The current status of quantitative characterization of terrain complexity by fractal theory is introduced.The scientificity of quantifying terrain complexity by using fractal theory is clarified.Second,the fractal is briefly described.Theoretical principles and characteristics are introduced in detail to the two common terrain complexity calculation methods of fractal scale-surface area and relative height difference method.Then,considering the terrain trend factor,the terrain trend factor index is defined to describe the surface shape Then,a quantitative analysis model of terrain complexity based on the scale-topographic trend factor frequency was established,and the results were compared and analyzed with the information entropy-based complex terrain quantification model to verify the reliability of the model.Finally,10 Wenchuan earthquakes were verified.The severely stricken area is the research area.Collecting remote sensing data and DEM data from 2008 to 2018,using an improved fractal model to quantify the complexity of terrain and landforms.According to the calculation results,the research area is divided into 5 levels,and the sensitivity index method is used for analysis.Spatial sensitivity of landslide disasters in the study area.The results of model construction and application analysis show that:(1)the improved fractal algorithm model can better express the terrain complexity.In addition to expressing the overall characteristics of the area,the description of local features of the terrain is more advantageous;(2)the more complex the terrain is,the more complex the area is.Landslide disasters continued to occur after the earthquake,and the landslide disaster sensitivity index showed a linear relationship with the terrain complexity.The effectiveness of this work was demonstrated by comparison with previous methods.Through the quantitative analysis model of terrain complexity constructed in this paper It will help post-disaster reconstruction and disaster prevention and reduction in extremely hard-hit areas.