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Based on graphical and quantitative methodology of landscape ecology and Geo-information Tupu, this paper studies the landscape spatial-temporal evolution characteristics of the Yellow River Delta (YRD), which was built up by periodic physical swings of the Yellow River (YR) rump channel during 1855-2000. According to the research on spatial-temporal evolution of YRD and YR rump channel, we conclude that the Qingshuigou channel has reached its limit and a new flow channel for YR should be built up sooner or later. It suggests that the shift of YR channel should abide by its natural rules of flowing through depressions among previous channels and could be carried out by artificial efforts. The paper discusses the problems and alternate ways out for treatment of the high content of silt in the YR flow at the estuary. [ABSTRACT FROM AUTHOR]

Great achievements have been gained in assuring the safety of the lower Yellow River through arduous work in the past fifty years. But the disadvantages of boundary for river-flow are obvious, such as topography, tectonic movement and crustal stability. The main conflicts of less water and more sand, and the speeding up of sedimentation still exist, causing continuous river shrinkage. However, all the existing methods cannot completely avoid flood catastrophe, so a new control method needs to be explored. The method of changing-route based on geographical theory has always been a focus of debate over whether there are other feasible routes for the current Yellow River. From geoscientific point of view, this paper investigates whether there is a best feasible reservation route in Huang-Huai-Hai plain. Under the actual condition that the conflict between water and sand cannot be eradicated, the selection of the best reservation route should be the overlaying area of the optimum boundary conditions and the less social and economic loss. By detailed analysis of topography, tectonic movement, crustal stability and social-economic progress in the region of the lower Yellow River, the best reservation route is obtained by using the distance weighted function and the minimum cost function. The analysis result indicates that the reservation route can get rid of the influence of the elevation in central western Shandong Province, and the whole route flows through the Hal-Huang rift valley, which is good for channel stability. As to the basic parameters of water and sand movements, the gradient increases 36.2%, the length shortens 15.4% and the curvature reduces 12.2%. Using the reservation route can comparatively reduce the flood risk of the Yellow River, except that it will induce such problems as resettlement and relocation of towns, infrastructure reconstruction, water shortage in the abandoned area of the present route, as well as the resultant ecological and environmental degradation. But in contrast to the huge accumulative input to the harnessing of the Yellow River by the state, the absolute input of dealing with the above-mentioned problems is still acceptable. In the construction of corresponding infrastructures, using the reservation route will promote the region's socio-economic development and offer a rare chance of burgeoning. [ABSTRACT FROM AUTHOR]