Study On Geomorphological And Landscape Characteristics Of The "Yellow River-Tower" Transect Based On UAV Remote Sensing

From the upstream of Yellow River's sediment was the main shaper of topography and landscape pattern within the city area north to the Yellow River. Area lying north to south, mainly in the plains, the surface morphology of the ladder-like distribution, from north to south, from high to low is the Beach of Yellow River, Beihewadi, plains and low-lying suburbs of the city.Yellow River form a plume of sand ridges and ripples in the river; River is limited to less than about 7 km apart on both sides of the levee, perennial river siltation resulting in the opening paragraph continue to uplift, forming higher than the urban surface about 10 meters, formed the typical "perched river "; Combined with artificially dug along the south bank levee shape the width of 3-4 km Beihewadi; Yellow River flood carried large amounts of sediment to the city of Kaifeng,because of the blocking of city protecting embankment, walls and other artificial fortifications, the surface elevation of positive side above the surface of the back water side.The Yellow River at the Liuyuankou Scour the South of Bank, so that the north shore sediment silt, forming vast area of the beach; the Yellow River beach affected by seasonal flooding, resulting in the floodplain wetlands and grassland landscape widespread; Beihewadi due to the shallow water table and the geographic location of near from the Yellow River, its more paddy fields, ponds landscape; Flood of the Yellow River barriered by the artificial fortifications that resulted in both sides of elevation different, shaping and changing area landscape pattern. This paper selects "Yellow- Tower" transect as a case, focusing on the status quo and reason of landscape and topography.The main results of the paper are as follows:(1) In this paper, using checkpoints of interpolation error evaluation method to verify DEM data with a different kind of precision grid size, while the amount of data for each grid size of DEM were statistics. When the grid size is less than 2.5m, DEM accuracy grows extremely slowly, but the amount of single image's data has grown exponentially, integrated DEM data accuracy and data size of unit DEM image, select the grid size of 2.5m as the optimum scale of DEM grid size.(2) Assess the accuracy of the data obtained that: Grid size of DEM data at 2.5m, the value curve of C is relatively smooth and slightly higher than 1, indicating that the accuracy of the DEM to obtain optimal grid size; The terrain complex area, the corresponding residual value is also higher than the area of relatively flat terrain, analysis the reasons may be the configuration of the terrain is relatively complex and multi-region vegetation landscape, resulting in images within shadow or covers result in reduced accuracy of mapping.(3) Based on the terrain profile to analyze the transect of local micro-topography changes and its causes in a micro perspective. From a micro perspective, the micro-topography complex and dramatic changes, especially in the vicinity of three fortifications showing significant local micro-topography variation, the reasons of this were that sedimentation of the Yellow River, the Yellow river floods and artificial fortifications.(4) In a macro perspective presents a significant gradient change, ladder elevation in descending order, that is, the Yellow River, Beihewadi, suburban and urban areas in space showing apparently changes in gradient, terrain showing decreasing trend. Adjacent ladder exists artificial fortifications, works on defense the Yellow River Flood, blocking effect of sediment, shaped the topography gradients in space, showing the topography gradients in space is the result of the Yellow River combined with effects of artificial defense project.(5)Landscape pattern showing a clear "strip" differentiation rule, are showing a "strip" of diversity discipline. Sequentially appears waters landscape, beach landscape, dry landscape, the landscape of paddy fields, ponds landscape, dry landscape and lake landscape from the Yellow River to Tower. Due to the influence of geomorphology, fortifications and other factors, local area appears differentiation in the small range of phenomena, the reason is the Yellow River, micro-topography, fortifications and other factors working together.