Comparing Terrain Factors Extracted By DEM Which Are Created By Different Spatial Interpolation, Contour Line And Resolution

Desert control is a human problem as well as a long-term task.Using GPS, TM and Google Earth data navigates to parabolic dune, this paper takes parabolic dune in Takeermohuer Desert in Yili as an example. Based on people who do much work on DEM,different spatial interpolation,different contour line DEM and different resolution DEM, it uses RTK to collect parabolic dune's elevation,uses different spatial interpolation to create DEM , extracts terrain factors and compares those factors.It selects better spatial interpolation to generate different contour line DEM and different resolution DEM,extracts terrain factors and compares those factors.Research results give basis to parabolic dune's applicability in scale.It is significant to do further study.At the same time, study on parabolic dune in Takeermohuer Desert in Yili will do great help to prevent sand and control sand.Conclusions are as follows:(1)This paper uses spline, kriging and idw to create DEM.Results tell DEM created by spline is more smooth than DEM created by kriging and idw.According to dune's feature, spline is better for parabolic dune's research.(2)With the increased contour line, curved contour simplify, the terrain of parabolic dune becomes flat and parabolic dune has been simplified.Comparing to DEM created by 0.1 meter contour line, DEM created by 0.2 meter contour line, 0.5 meter contour line, 1 meter contour line and 2 meter contour line loss informations.But data and operation number of DEM created by 0.2 meter contour line, 0.5 meter contour line, 1 meter contour line and 2 meter contour line are fewer than that of DEM created by 0.1 meter contour line,and macro information is more apparent. The data of DEM created by 1 meter contour line and 2 meter contour line loss a lot .It is not good to study dune.So in order to study dune's dynamic change,we can select DEM created by 0.1 meter or smaller contour line and to study dune's pattern, we can select DEM created by 0.2 meter contour line and 0.5 meter contour line.(3)With the increased resolution, parabolic dune's slope reduce in the overall. The terrain of parabolic dune becomes flat.The parabolic dune has been simplified.In the range of parabolic dune's slope, slope become the middle .Data of DEM created by 0.2 meter resolution, 0.5 meter resolution, 1 meter resolution and 2 meter resolution loss a lot.But data and operation number of DEM created by 0.2 meter resolution, 0.5 meter resolution, 1 meter resolution and 2 meter resolution are fewer than that of DEM created by 0.1 meter resolution,and macro information is more apparent .The Data of DEM created by 1 meter resolution and 2 meter resolution loss a lot .It is not good to study dune.In order to study dune's dynamic change, we can select DEM created by 0.1 meter or smaller resolution and to study dune's pattern, we can select DEM created by 0.2 meter resolution and 0.5 meter resolution.