Research Of Key Technology Of Water Erosion Simulation In Loess Slope

The Loess Plateau is one of the most serious soil erosive regions in the world, the erosion model of it is complex, and involves plenty of spatial data, therefore it is a key technology to find a way that visualizing the predictive data in the field of study on erosion model. As the increasing of variety and complexity for cause of formation for water and soil loss, traditional water erosion models can not depict present specific situations of the Loess Plateau synthetically, from the status of steep slope and gully erosion, using computer software to simulate the erosion model, and changing the erosion parameters to graphic map are becoming a deserved research direction. As a result, the development of Geographic Information System in the study of soil and water loss domain provids new thoughts and methods for analysis of spatial data of erosion model, to the question of the deficiency of unitary function of ComGIS, which can not develop simulation in three-dimension independently, Virtual Reality should be applied to achieve the fundamental functions of 3D GIS.Aiming at these problems above,this thesis mainly studied on how to combine with kinds of parameters and spatial information maps of water erosion research on slope on a identical platform organically, carried out correlated factors to water erosion in two- dimension by using ComGIS firstly. Secondly, accomplished visualization of intermediate results at water erosive model's calculation on slope scale, forth more, the function of calculation was embed into the ComGIS module, and then changed the results of those to graphic maps. Finally, generated the conformation of landscape on slope by means of simulating the geomorphologic shape in 3D, besides, simulated the process of scene transformation dynamically. The primarily achieved works have beem done as following:(1) Studied on spatial data structure of MapX model, adopted MapX to organize and manage the abstract geographic information as the pattern of digital maps,then integrated VC++ to realize establishment of thematic maps, overlay of layers, analysis of slope and aspect for digital maps, qualitatively analyzed the causes and internal relations of water erosion from the perspective of Landscape Ecology.(2) Investigated the principle of water erosion model, designed the software of calculation of loss amount, and analyzed quantificationally intensity of water erosion, based on this module, water erosion rule of loess slope's typical testing areas were calculated and contrasted. At last, the method of data binding from water erosion data to GIS functional module was explored to transform factors to maps, contacted factors and spatial maps, created thematic maps for results of numerical value computing as well as.(3) Researched theories of fractal Brown motion and fractal dimensions of landscape, virtual landscape of slope was constituted with the help of the random mid-point displacement algorithm, and increased sky and terrain textures by OpenGL technology to enhance the reality of sense. After that, went deep into dynamic process of water erosion on slope, displaied the water erosion process in 3D.After the investigation, it could provide visualized calculation of erosion model for the circumstances of water and soil loss on the Loess Plateau, analyzed spatially 2D maps of erosive spatial data, virtualized the erosive landscape on slope in 3D and simulated the process of water erosion dynamically. In a word, it implemented simulation of numerical value and images of soil erosion research.