Research On The Loess Slope-Landscape Structure Based On DEM

Slope-landscape structure refers to spatial arrangement and relationship of slope with different slope forms and slope positions. Slope is the basic component of ground surface. Changes of various landscapes can be directly regarded as changes of the slopes characteristic and combination. In nature, different slope positions (e.g. slope shoulder, back slope, toe, etc.) and slope forms (such as the concave slope, convex slope, straight slope, etc.) result in different characteristics presented by many geographical processes (such as the soil, hydrology, geomorphology, etc.) and the associated man-land systems. Therefore, the slope information is of great significance for the study of geographical or ecological processes related with terrain. In this study, we study the slope forms as entry point, and discuss the spatial structure of loess slope in different geomorphology areas to better recognize spatial pattern of loess geomorphology form.With high resolution DEM as data source and the introduction of object-based image analysis method, we extract slope-landscape elements based on eCognition software. On this basis, combined with quantitative methods of landscape ecology, we analyze slope-landscape structure and its spatial distribution in Shanbei Loess Plateau quantitatively from horizontal and vertical angles. The results show that slope-landscape horizontal structure shows relatively consistent rules from three aspects (number, shape, spatial distribution). Slope-landscape vertical structure is characterized by almost the same rule, only a little differences between six geomorphology plots from north to south. Spatial distribution of slope-landscape structure in the Loess Plateau shows gradually variation in two directions S-N and W-E. Slope-landscape structure shows spatial sequence in Shanbei Loess Plateau, corresponding to spatial distribution sequence of the loess plateau geomorphology.This research discusses the quantitative analysis of loess landform from a new perspective. It's an effective extension of Loess Plateau digital terrain analysis theory and methodology and useful exploration of loess landform spatial pattern.